Patent Publication Number: US-6221189-B1

Title: Method for manufacturing thermoplastic tubes

Description:
CROSS REFERENCE TO RELATED APPLICATIONS 
     This application is related to three applications: “Machine for Manufacturing Thermoplastic Tubes”, Ser. No. 09/200,054, filed even date herewith in the names of Ronald E. Kieras and John J. Rhoades; “Process Control Method for a Machine for Manufacturing Thermoplastic Tubes”, Ser. No. 09/199,643, filed even date herewith in the names of Ronald E. Kieras, John J. Rhoades and Thomas A. Frazier, now U.S. Pat. No. 6,165,295; and “Plant for Manufacturing and Packing Thermoplastic Tubes”, Ser. No. 09/199,617, filed even date herewith in the names of Ronald E. Kieras and John J. Rhoades, now U.S. Pat. No. 6,047,525, which applications are assigned to the assignee of the present application and incorporated by reference herein. 
    
    
     FIELD OF THE INVENTION 
     The present invention is a method for manufacturing thermoplastic tubes from thermoplastic sleeves. 
     BACKGROUND OF THE INVENTION 
     The machinery commonly used today for making finished, headed thermoplastic tubes from 2 to 10 inches in length and from ½ inch to 3 inches in diameter comprises a series of machines arranged linearly and having a total process line length of about 80 to 100 feet and a total height of about 20 to 30 feet. Process lines of such dimensions are housed in factories often having several acres of floor space. 
     A conventional process line for producing a single type of thermoplastic tube in today&#39;s manufacturing plants includes machines for heating raw polymer material into molten plastic; extruding the molten plastic through a die to form an extruded, stretched hollow body; cooling and then cutting the hollow body into sleeves of equal lengths; transporting the sleeves to a machine for molding a head on one end of the sleeves to form headed tubes; transporting the headed tubes to another machine for decorating or applying a graphic to the headed tubes; transporting the printed tubes to yet another machine for applying a coating; transporting the printed tubes to a different machine for applying a cap to the headed end of the tubes and transporting the capped tubes to a final machine for unloading the tubes from the process line. The removed tubes are then packed for inventory or shipment. 
     Such a process line requires at least four workers during operation, with one worker at the extrusion machine, at least two workers along the line to monitor the tube conveyors and other various machines and a final worker to pack the finished tubes at the end of the line. 
     Increasing size has dominated production equipment design in an effort to take advantage of economies associated with large size. A conventional process line can simultaneously handle several hundred tubes in different stages of production. While some production advantages can be achieved by large size, many limitations exist, even in view of the giant size of the machinery. 
     Conventional process lines have inherent manufacturing inefficiencies dictated by several factors such as those associated with the line machinery itself namely: large scale, mechanical operation, and process limitations as well as other inefficiencies like unit cost limitations. Manufacturing inefficiencies, like those described below, are serious barriers which ultimately can limit the varieties of tubes available in the market. 
     Large scale processing machines have land, capital, and labor requirements, the costs of which are high. Additionally, large scale equipment is complex and as a result it requires more labor and higher skilled labor to operate and maintain. Most importantly, large scale design does not necessarily improve total efficiency. While production capacity may be increased, it may be done at the cost of efficiency. Complex machines require a significant amount of capital, time and labor input which can mean low overall efficiency when compared to the output. 
     The mechanical operation of conventional line machinery can add inefficiency to the manufacturing process. Process line down-time is inevitable because of the mechanical constraints of current machinery. For example, about 70% to 80% of line down-time is attributable to the tube and sleeve conveyor systems. One process line will have several transport systems, each system typically being a long chain with tube holding mandrels spaced every couple of inches, wrapped around many drive gears. These chain systems easily become jammed, frequently deliver improperly positioned articles to the process machinery and often need to be stopped for adjustment and resetting. As a result of stopping one transport system, the entire manufacturing line must be shut down. 
     Line down-time results in production loss. If one of the processing machines on the line malfunctions on the night shift, for example, when an engineer is not available to correct the problem, the entire line will be stopped and it will remain idle until morning. This loss is inefficient and costly to a manufacturer. 
     The inflexibility of the production equipment creates inherent constraints on the manufacturing process. Line equipment cannot easily be rearranged to effectuate different manufacturing processes because the individual machines weigh several thousands of pounds and are not readily mobile. Furthermore, large scale machines are built for a single purpose and are limited to that purpose. For example, offset printing machines are limited to printing articles by the offset printing method. Thus the arrangement of production equipment limits the number of processing methods available to a manufacturer. 
     Process control for monitoring and controlling the quality of each individual tube product is not commercially available for adaption to current machinery. For example, there is no known practical way to identify, monitor and track defective products during the manufacturing process. Defective products are removed only at the end of the line. When a defect occurs on a tube at the beginning of the line, continued processing of that tube is inefficient since the tube will eventually be discarded. 
     Because an 80 to 100 foot tube production line requires at least four laborers per shift, has a predictable defect rate, requires time to retool for each job and costs money even to remain idle, it creates a high manufacturing cost that can only be lowered by large production jobs. It is a waste of resources to manufacture small numbers of tubes on such large machinery because the manufacturing cost per tube is too high. Conventional process lines can be limited to certain size manufacturing jobs in order to recapture manufacturing costs. 
     While the output of a single machine of the present invention does not compare to the production capacity achieved by one conventional 80 to 100 foot processing line, if the output of one simple efficient machine is multiplied by the use of a series of such machines, then the total output of the series of machines can rival the conventional process lines. Thus, where efficiency is maximized and multiplied, a great number of thermoplastic tubes may be produced. 
     OBJECTS OF THE INVENTION 
     It is the principle object of the invention to provide a method for manufacturing thermoplastic tubes that more efficiently uses land, labor and capital, as compared to conventional manufacturing methods. 
     It is an object of the present invention to provide a flexible method for manufacturing thermoplastic tubes to accommodate different manufacturing process methods. 
     It is a another object of the present invention to provide a method for manufacturing thermoplastic tubes which can mark, identify, index and track every thermoplastic article being handled. 
     It is yet another object of the present invention to provide a method that provides an operating environment substantially free of contaminants, such as dirt and dust, for manufacturing thermoplastic tubes suitable for the pharmaceutical industry. 
     It is a further object of the present invention to provide a method for manufacturing thermoplastic tubes of improved quality. 
     It is yet a further object of the present invention to provide a method for manufacturing thermoplastic tubes which can accommodate large numbers of tubes as well as small numbers of tubes at similar operational costs. 
     It is still a further object of the present invention to provide a method for manufacturing thermoplastic tubes which can use a programmable logic controller. 
     It is a specific object of the present invention to provide a method for manufacturing thermoplastic tubes which can monitor and confirm the integrity of each manufacturing process step. 
     Other objects, features and advantages of the present invention will become apparent from the following detailed description taken in conjunction with the accompanying drawings. 
     SUMMARY OF THE INVENTION 
     A method of manufacturing thermoplastic tubes from thermoplastic sleeves having the following steps: 
     providing an indexing device rotatable about a shaft; 
     providing means for supporting sleeves i.e.) mandrels, mounted on the indexing device; 
     loading sleeves onto the mandrels in a first location of a closed manufacturing path; 
     advancing the sleeves mounted on the mandrels along the closed path in response to rotating the indexing device relative to the closed path in a predetermined direction; 
     forming a head on the sleeves to create tubes in a second location of the closed path downstream of the first location; 
     decorating the tubes in a third location of the closed path downstream of the second location; and 
     unloading the tubes from the supporting means in a fourth location of the closed path downstream the third location between the third and the first locations. 
     Additionally, accurate process control may be added to the method which creates labor savings, improves efficiency and reduces product waste. 
    
    
     BRIEF DESCRIPTION OF THE DRAWINGS 
     FIG. 1 is a schematic view of a machine of the present invention of a first embodiment having a PLC device; 
     FIG. 2 is a schematic view of a single prior art process line for manufacturing thermoplastic tubes; 
     FIG. 3 is a schematic view of an arrangement of three manufacturing machines of the present invention for manufacturing thermoplastic tubes; 
     FIG. 4 is a schematic view of the machine of the first embodiment without the PLC device, shown only with an indexing table, holding mandrels, and a mounting ring for mounting manufacturing stations; 
     FIG. 5 is a schematic view from the rear of the machine of FIG.  4 . 
     FIG. 6 is a schematic view of a housing for seating a holding mandrel in an indexing table; 
     FIG. 7 is a schematic view of a machine of the first embodiment without the PLC device shown with supply and removal means; 
     FIG. 8 is a schematic view of the machine of the first embodiment without the PLC device shown from a lower perspective; 
     FIG. 9 is a schematic view of the machine of the first embodiment shown from the front with various stations identified; 
     FIG. 10 shows the relative locations of fourteen different manufacturing stations located around the circumference of an indexing table, comprising a second embodiment of the machine of the present invention; 
     FIG. 11 is a schematic view of an indexing table and the fourteen manufacturing stations of FIG. 10; 
     FIG. 12 is a schematic view of a load station; 
     FIG. 13 is a schematic view of a preheat station or heat station; 
     FIG. 14 is a schematic view of a heating probe of the preheat or heat stations shown in FIG. 13; 
     FIG. 15 is a schematic view of a mold station; 
     FIG. 16 is a cross-sectional view of a mold die used in the mold station of FIG. 15; 
     FIG. 17 is a schematic view of a treat station; 
     FIG. 18 is a schematic view of a label station; 
     FIG. 19 is a schematic view of a print station; 
     FIG. 20 is a schematic view of a cure station; 
     FIG. 21 is a schematic view of a coat station; 
     FIG. 22 is a schematic view of a tab seal station; 
     FIG. 23 is a schematic view of a cap station; 
     FIG. 24 is a schematic view of a torque station; 
     FIG. 25 is a schematic view of an unload station; 
     FIG. 26 is a schematic view of a sonic welding station; 
     FIG. 27 shows the locations of twenty manufacturing stations along the edge of an indexing table, with each manufacturing station associated with a PLC device, which is a third embodiment of the present invention; 
     FIG. 28 is a schematic view of the twenty manufacturing stations of FIG. 27; 
     FIG. 29 is a schematic view of an inspection station; 
     FIG. 30 is a schematic view of a confirmation station; 
     FIG. 31 is a schematic view of a reject station; 
     FIG. 32 is a schematic view of the machine of a fourth embodiment; 
     FIG. 33 is a schematic view from the front of the machine of FIG. 32; 
     FIG. 34 is a schematic view of a machine of a fifth embodiment; 
     FIG. 35 is a schematic view from the front of the machine of FIG. 34; 
     FIG. 36 is a schematic view of a machine of a sixth embodiment; 
     FIG. 37 is a schematic view from the front of the machine of FIG. 36; 
     FIG. 38 is a schematic view of a machine of a seventh embodiment; 
     FIG. 39 is a schematic view of a machine of an eighth embodiment; 
     FIG. 40 is a schematic view of a machine of a ninth embodiment; 
     FIG. 41 is a schematic view from the front of the machine of FIG. 40; 
     FIG. 42 is a schematic view of a machine of a tenth embodiment; 
     FIG. 43 is a schematic view from the front of the machine of FIG. 42; 
     FIG. 44 is a schematic view of a machine of an eleventh embodiment; 
     FIG. 45 is a schematic view from the front of the machine of FIG. 44; 
     FIG. 46 is a schematic view of one embodiment of an indexing drum; and 
     FIG. 47 is a schematic view of a machine of the present invention with an indexing drum as the indexing device; 
     FIG. 48 illustrates pressure being applied to the conical shaped exposed portion of the thermoplastic extruded sleeve and contact with a reusable closure means to form a head; 
     FIG. 49 illustrates a finished headed thermoplastic tube having a reusable closure means on the forming mandrel prior to release therefrom; 
     FIG. 50 is an enlargement of the circled portion of FIG. 49 showing a threaded fit of the reusable closure means with the thermoplastic tube; 
     FIG. 51 illustrates a bullet-shaped preform mass; 
     FIG. 52 illustrates heating of the exposed inner wall surface of the exposed portion of the thermoplastic extruded, stretched, horizontally disposed sleeve by a hot fluid while rotating the sleeve, as shown by the arrow; and 
     FIG. 53 illustrates the shaping of the heated exposed portion of the thermoplastic extruded horizontally disposed sleeve into a conical shape while rotating the sleeve, as shown by the arrow. 
    
    
     DETAILED DESCRIPTION 
     I. Organization 
     This specification is organized into the following sections: 
     I. Organization 
     II. Introduction 
     1) Conventional Manufacturing Machinery 
     2) The Machine of the Present Invention 
     III. Manufacturing with a Machine of the Present Invention 
     1) Loading Thermoplastic Sleeves 
     2) Forming a Head on Thermoplastic Sleeves 
     3) Decorating Thermoplastic Tubes 
     4) Finishing Thermoplastic Tubes 
     5) Unloading Thermoplastic Tubes 
     6) Additions and Alternatives 
     7) Large Scale Manufacturing 
     IV. Manufacturing with a Programmable Logic Controller 
     V. Manufacturing Example 
     VI. Further Embodiments 
     The machine of the present invention, the method of manufacturing with the machine and the process control of the machine are summarized in the Introduction. Next the machine and method of manufacturing are described in detail as the machine and method would be utilized to manufacture thermoplastic tubes from thermoplastic sleeves. Manufacturing with a programmable logic controller is described followed by a manufacturing example and further embodiments of the machine of the present invention. 
     II. Introduction 
     The machine of the present invention manufactures thermoplastic tubes from thermoplastic sleeves by a variety of different process methods. The machine is a single apparatus having an indexing device transportation means, i.e) an indexing table or indexing drum, with a plurality of mandrels for holding hollow thermoplastic sleeves for the purpose of transporting the same around a closed manufacturing path. The manufacturing path of the machine of the present invention comprises a series of stations which have mechanical devices for carrying out the manufacturing steps necessary to produce thermoplastic tubes from thermoplastic sleeves. 
     A tube, as the term is used herein, refers to any thermoplastic sleeve having at least a head on one end. A sleeve, as the term is used herein, is a hollow body of a discrete size of any shape. A sleeve may be fabricated from a sheet, extruded in sleeve form, or made by any other known means. The sleeves used in the present invention are preferably cut from an elongated longitudinally stretched and extruded thermoplastic hollow cylinder. 
     The thermoplastic tubes produced according to the present method can be formed from various thermoplastic materials. Such thermoplastic materials include, but are not limited to, high density polyethylene, low density polyethylene, polypropylene, a polyester such as polyethylene terephthalate, polycarbonates, polyvinyl chloride, and the like. 
     Thermoplastic tubes may also be formed from multi layers or laminates of various plastic materials, such as a layer of an oxygen-impermeable material comprising a polyamide such as nylon, or ethylene polyvinyl alcohol, a polyvinylidene chloride or the like sandwiched between two polyethylene outer layers. Also, five layer composites comprising an outer layer and an inner layer of a thermoplastic such as polyethylene, polypropylene, a polyester such as polyethylene terephthalate, an intermediate layer of an oxygen-impermeable material, and adhesive layers between the oxygen-impermeable material and the outer and inner layers of thermoplastic to bond the same, can be used to form thermoplastic tubes according to the present method. 
     Thermoplastic tubes are formed from a flexible material and are readily squeezable and collapsible to force the contents of the tube out of an orifice formed in the end of the tube at the head portion. They are generally of a size having a wall thickness of the sleeve portion of between about 0.010 to 0.040 inch in thickness, while a shoulder and a neck portion of the tube will be thicker than the wall of the sleeve, generally between 0.035 to 0.045 inch thick. Since the tube is preferably formed from an extruded sleeve, the wall thickness of the sleeve portion will be very uniform, with a variance in wall thickness of the sleeve portion being only about + or −10 percent. 
     Preferably the extruded sleeve from which the thermoplastic tube is formed is a sleeve cut from an extrusion which has a wall thickness in the molten state preferably two to three times the wall thickness of the final cooled extruded thickness. The extrusion from which the sleeve is cut can be of any shape. Consequently, the sleeve cut from the extrusion can take the shape of the extrusion like cylindrical, oval, elliptical, rectangular or any other shape. The shape of the sleeve used in the present invention is typically cylindrical. Such a tubular extrusion, as is known, is formed by extruding thermoplastic material from an extrusion annulus in a molten state and stretching the hot tubular form, in the direction of the longitudinal axis, into a tube or sleeve having a wall thickness one-half (½), one-third (⅓), or less, than the extrusion annulus. Such a stretch oriented extruded sleeve, when heated above the glass transition temperature of the thermoplastic material, due to the plastic memory of the thermoplastic material, will increase in thickness to the thickness of the molten material exiting the extrusion annulus, and shrink in length, thus providing sufficient molten plastic mass to form a head on the sleeve according to the present method. When using high density polyethylene (HDPE) or low density polyethylene (LDPE), for example, the annulus would extrude a tubular form of about 1.5 inch in diameter having a wall thickness between about 0.040-0.046 inch, which would be stretched into a stretch oriented extruded sleeve of about 1.0 inch in diameter having a wall thickness between about 0.015-0.018 inch. The final thermoplastic sleeves used in the present invention can be of any typical diameter such as ½, ⅝, ¾, ⅞, 1, 1{fraction (3/16)}, 1⅜, 1½ and 2 inches. 
     In addition to forming a head on a thermoplastic sleeve, there are many other manufacturing process steps that may be performed on a thermoplastic sleeve such as decorating, securing a cap to the headed end, marking articles with indicia, etc. All manufacturing steps are performed by the manufacturing stations located around the closed manufacturing path. 
     The stations of the manufacturing path of the present machine are modular so that they may be removed, added or rearranged; the stations may be optionally connected to a programmable logic controller (PLC) and may optionally have sensors for information feedback to the PLC device and feedback process control. The flexibility to add, remove or rearrange manufacturing stations gives the machine of the present invention the capacity to carry out a variety of different manufacturing methods for making thermoplastic tubes. 
     The configuration of the machine of the present invention i.e.) the configuration of the indexing device, manufacturing path and optional PLC device, depends on the desired tube to be produced. If only a simple tube is desired than the machine may be configured with the minimum stations necessary, namely a load station; a station for forming a head; and an unload station. Such a machine may also be appropriate if the sleeves are previously decorated or preprinted and only the manufacturing of a head is desired. If a decorated tube with a cap secured to the headed end is desired then the machine can be arranged with additional stations for decorating and securing a cap to the tube. 
     FIG. 1 illustrates a machine  1  of the present invention of a first embodiment having a indexing table  3  rotatable in a predetermined direction and housed in a frame  5  and mounted, by mounting bolts  7 , on a fixed shaft  61  (FIG. 5) associated with an indexer  63  (FIG.  5 ). Indexing table  3  has a plurality of mandrels  9  mounted thereon for holding thermoplastic sleeves. 
     Adjacent each mandrel  9  on machine  1  is a manufacturing station  11 , mounted on a mounting ring  13 , for performing a process step on a sleeve mounted on each mandrel  9 . The configuration of manufacturing stations  11  on mounting ring  13  comprises the manufacturing path. The manufacturing path is closed or endless because the first station in the path is adjacent to the last station in the path. All sleeves are transported around the manufacturing path by the indexing table  3 . All manufacturing stations  11  of the manufacturing path may be connected to a PLC device  15 , as shown by the dashed lines. Indexing table  3  rotates relative to the manufacturing stations  11 . A base plate  17  with a plurality of leveling legs  19  supports frame  5 . In another configuration, PLC device  15  may be housed on base plate  17 . 
     The embodiments shown and described herein describe a machine of the present invention, a method of manufacturing with the machine and a process control of the machine. The embodiments do not intend to encompass every possible variation, configuration and combination of the machine, method of manufacturing, and process control within the scope of the present invention. Other embodiments will be apparent to those skilled in the art. 
     1) Conventional Manufacturing Machinery 
     There is shown in FIGS. 2 and 3 a schematic view of the relative lengths of a conventional process line (FIG. 2) which is between 80 and 100 feet long and an arrangement of three machines of the present invention, about 30 feet long in length associated with a common conveyor (FIG.  3 ). Each arrangement in FIGS. 2 and 3 includes one machine for extruding a hollow thermoplastic body and cutting the body into thermoplastic sleeves of equal lengths. 
     In the conventional manufacturing process, the thermoplastic sleeves travel along a path 80 to 100 feet in length where the sleeve is formed into a thermoplastic tube which can be decorated, sealed with protective material and capped. Conversely, with only a single machine used in a plant of the present invention, a thermoplastic sleeve is loaded onto the machine whereby it travels around a closed path only a few feet in length where the sleeve is formed into a thermoplastic tube which may also be decorated, protective sealed and capped on the same manufacturing path. 
     Referring to FIG. 2, the machine  21  for extruding, cooling and cutting thermoplastic sleeves is followed by a loading machine  23  which loads thermoplastic sleeves onto a transportation belt  25  which transports the sleeves to a machine  27  for forming a head on one end of the sleeves. The resulting headed thermoplastic sleeves, which are now considered as thermoplastic tubes, are transported by a system  29  to a printing machine  31  for decorating the exterior of the thermoplastic tubes. The decorated thermoplastic tubes are then transported by a conveyor  33  to a capping machine  35  where a cap is snapped or screwed onto the headed end of the thermoplastic tubes. Finally, the capped tube is unloaded from the process line by an unloader  37  and transported by a conveyor  39  to a packing machine  41 , where the tubes are packed for shipment. 
     By comparison, an arrangement of three machines  43 ,  45  and  47  is shown in FIG.  3 . The arrangement includes a machine  49  for extruding, cooling and cutting thermoplastic sleeves followed by a loading machine  51  for loading thermoplastic sleeves onto a conveyor system  53 . The sleeves travel down conveyor system  53  where they are loaded onto one of the three machines  43 ,  45  and  47  by mechanical feeders  55 ,  57  and  59 . Machines  43 ,  45  and  47  transport the sleeves around a closed path only a few feet in length where the sleeves are transformed from blank sleeves into finished thermoplastic tubes by the action of several manufacturing stations located around the closed path. 
     The machine of the present invention uses significantly less sleeve and tube handling transfers compared to conventional tube manufacturing machines. This reduction, due in part to the compactness of the manufacturing path on the machine, improves efficiency and reduces the cost and time of the tube manufacturing process. In fact, the total time of manufacturing from resin pellet to finished tube is a few minutes as compared to at least a half an hour on conventional machinery. The machine of the present invention may be built to fit in a 4×4 foot area. 
     2) The Machine of the Present Invention 
     FIGS. 4-9 illustrate, in greater detail, machine  1  of the first embodiment that may be used as one of machines  43 ,  45  and  47  shown in arrangement in FIG.  3 . FIG. 4 shows mandrels  9  of machine  1 , shown without PLC device  15 . Mandrels  9  are evenly spaced on indexing table  3 . Indexing table  3  is typically a circular plate. While the preferred embodiment of indexing table  3  is an aluminum plate, indexing table  3  may be substituted by any other means which transports sleeves around a closed manufacturing path. 
     The manufacturing stations  11  of the closed manufacturing path (FIG. 1) are mounted and arranged on a support, such as mounting ring  13  (FIG.  4 ). Mounting ring  13  supports manufacturing stations  11  in a position such that manufacturing stations may perform a process step on a sleeve or tube on mandrel  9 . In the embodiment in FIG. 1, mounting ring  13  supports manufacturing stations  11  so that they are adjacent to and in front of a corresponding mandrel  9 . Alternatively, stations  11  could be mounted on a frame (not shown) in the same plane as indexing table  3  so that manufacturing stations are beside a corresponding mandrel  9 . 
     FIG. 5 is a perspective view from the rear of machine  1  of FIG. 4, showing indexing table  3  connected to a shaft  61  rotatably mounted on an indexer  63 . Indexer  63  may be conveniently mounted on frame  5 . 
     Indexer  63  is a means for rotating or advancing indexing table  3  in a step-wise or incremental manner so that sleeves loaded onto mandrels  9  stop at each manufacturing station of the closed path for a time period long enough to effectuate a manufacturing process step. Indexing table  3 , of this embodiment, rotates counterclockwise. 
     FIG. 6 illustrates a housing assembly  65  for mandrel  9  on indexing table  3  of machine  1 . Housing assembly  65  at the base of mandrel  9  allows mandrel  9  to rotate smoothly at various speeds, which is necessary for certain manufacturing steps. Inside housing assembly  65  are two rings  67  and  69  of ball bearings separated by a bearing spacer  71 . A bearing clamp  73  is also added to housing assembly  65  for support. At one end of mandrel  9  is mounted a mandrel pulley  75  for improved weight distribution and a means to rotate mandrel  9 . The desirable housing assembly  65  materials are durable materials, such as metal, because the components of housing assembly  65  wear. 
     FIGS. 7 and 8 show perspective views of machine  1 . FIG. 7 shows machine  1  with pickle sorter  77  which supplies sleeves directly to load station  79 . FIG. 7 also shows unload chute  81  which transports tubes from machine  1  that have been removed by unload station  83  from indexing table  3 . FIG. 8 shows, in greater detail, the relative locations of load station  79 , unload station  83  and the remaining manufacturing stations. 
     To make machine  1  operable, machine  1  must be connected to a power source and other additional input sources as necessary, such as compressed air, water, electricity, steam, heated air, etc. 
     In additional to supplying sleeves to machine  1 , other raw materials such as caps, formed heads, etc. may be necessary for the manufacturing process. 
     FIG. 9 schematically shows the configuration of the  12  manufacturing stations  11  of machine  1 , all connected to PLC device  15 . The manufacturing stations and corresponding manufacturing process steps shown are: (A) load, (B) preheat, (C) heat, (D) mold, (E) treat, (F) print, (G) cure, (H) coat, (I) cure, (J) cap, (K) torque and (L) unload. 
     The minimum process steps necessary to form a tube from a sleeve are: loading the sleeve on the machine, forming a head on the sleeve, and unloading the headed sleeve. Besides the minimum steps, many other finishing or intermediate steps may be performed by additional manufacturing stations to produce a product of higher complexity. 
     For example, machine  85  a second embodiment of a machine of the present invention represented schematically in FIG. 10, has  14  stations located adjacent to each of  14  mandrels  87  mounted on indexing table  89 , which rotates counterclockwise via indexer  91  (FIG. 11) in this embodiment. The  14  different stations and corresponding process steps are as follows: (A) load, (B) preheat, (C) heat, (D) mold, (E) treat, (F) label, (G) print, (H) cure, (I) coat, (J) cure, (K) tab seal, (L) cap, (M) torque and (N) unload. 
     FIG. 11 is a perspective view of machine  85  of FIG. 10, showing partial illustrations of manufacturing stations (A) through (N). Machine  85  has three different decorating stations, (F) label, (G) print and (I) coat. It is unlikely that a manufacturing process would employ all three stations. Typically, only one or two of the decorating stations would be operable. Non-operable stations may be turned off manually or by a PLC device or they may be removed. 
     III. Manufacturing with a Machine of the Present Invention 
     Again the configuration of the indexing device, manufacturing path and optional PLC device, depends on the desired tube to be produced. A decorated, sealed and capped tube will be produced using machine  85 , a second embodiment of a machine of the present invention, illustrated in FIGS. 10 &amp; 11 having  14  stations. All  14  manufacturing stations belonging to machine  85  are described below. 
     Each manufacturing station comprises a device for performing a manufacturing step and a means for mounting the device on a support or frame, like mounting ring  13  of FIG.  1 . The mounting means may include a portion which is adjustable, like an X-Y positioning table, so the relative location of the device to the sleeve holding mandrel may be changed. The adjusting may be done manually or optionally by PLC control. The manufacturing stations operate continuously and may be coordinated with the rotation of the indexing device. 
     The manufacturing stations of the second embodiment shown in FIG. 11 may be grouped into five general process steps: 1) Loading, 2) Forming a Head, 3) Decorating, 4) Finishing and 5) Unloading. As will be described below there are many ways to effectuate the manufacturing process steps to create decorated, sealed and capped tubes. 
     1) Loading Thermoplastic Sleeves 
     After transporting sleeves to a machine of the present invention each sleeve is loaded on a mandrel on the indexing device at a load station. The load station comprises a loading device that can load a sleeve onto a mandrel which is about 0.005 inch smaller in diameter than the sleeve, to provide a snug fit and a means to mount the loading device to the frame of the machine. Preferably, the sleeve should be loaded and positioned so that one end of the sleeve extends a predetermined distance over one end of the mandrel. 
     The loading device may be conventional device: a pneumatic push rod, a cam driven push rod, an advancing and retracting linear actuator, a crank motion device or a servo-motor driven push rod. The preferred loading station, a pneumatic push rod, is described below as load station (A). 
     (A) Load Station 
     FIG. 12 illustrates the preferred embodiment of load station (A), which loads and positions sleeves onto mandrel  87  on indexing table  89 . Load station (A) comprises a pneumatic loading device and a means for mounting the loading device to a frame or a mounting ring, like mounting ring  13  of FIG.  1 . In this embodiment, pneumatic loading device comprises a pneumatic push rod  93  which pushes sleeves supplied to cradle loader  95 , by pickle sorter  77  as shown in FIG. 7, onto mandrel  87 . 
     Pneumatic push rod  93  is driven back and forth along cradle loader  95  by air cylinder  97 , supplied with air by air lines  99 , positioned behind cradle loader  95  on a mounting bracket  101 . Mounting bracket  101  is further mounted on mounting plate  103  which is attached to a mounting ring or equivalent, like ring  13  of FIG.  1 . 
     Cradle loader  95  has a “V” shaped surface  105  for aligning the center axis of a thermoplastic sleeve resting on V-shaped surface  105  with the center axis of mandrel  87 , so the sleeve may be loaded onto mandrel  87 , with a clearance as small as 0.005 inch, without damage. Cradle loader  95  is secured on mounting plate  103 . 
     Both cradle loader  95  and air cylinder  97  are mounted on a portion of mounting plate  103  that is adjustable relative to the location of mandrel  87 , much like an X-Y positioning table. The adjustment may be done manually by a X-axis adjustment rod  107  and a Y-axis adjustment rod  109 . Alternatively the adjustment could be controlled by a PLC device. 
     Load station (A) operates as follows: A sleeve is supplied to V-shaped surface  105  of cradle loader  95  from a supply means. When the center axis of the sleeve is aligned with the center axis of mandrel  87 , push rod  93  pushes the sleeve along V-shaped surface  105  so that the sleeve loaded onto mandrel  87  and preferably positioned with a portion extending over the end of mandrel  87  so that an end is exposed. 
     The ideal cradle loader has a low coefficient of friction and a surface that will not mark or scratch sleeves which rest on the surface. Possible materials that have a non-marking surface with a low coefficient of friction are Teflon and Delrin, a type of lubricated nylon. 
     After sleeve is loaded onto mandrel  87 , indexing table  89  advances or “indexes” one position and stops again so that the loaded sleeve is adjacent to the next station downstream load station (A) in the closed manufacturing path. 
     2) Forming a Head on Thermoplastic Sleeves 
     In the preferred embodiment, a head is formed on the exposed end of the loaded sleeve by first heating the exposed end above the glass transition temperature so the thermoplastic is molten and then forming the molten thermoplastic into a head with a mold die or equivalent device. 
     In this embodiment, a single indexing device supports sleeves and tubes in a variety of different stages of manufacturing. The speed of rotation of the indexing device is limited by the speed of the slowest manufacturing step. In this embodiment time is conserved by dividing the heating step between two stations, a preheat station and a heat station. 
     Machine  85 , of the second embodiment, formes a head on a thermoplastic sleeve by the separate steps of preheating, heating and molding. Three manufacturing stations are used, preheat (B), heat (C) and mold (D). 
     (B) Preheat Station 
     FIG. 13 illustrates preferred preheat station (B), located downstream from load station (A). Preheat station (B) heats the portion of a sleeve which extends beyond the end of mandrel  87  above the glass transition temperature to create a molten thermoplastic mass for molding into a head. Preheat station (B) has a heating device secured to a movable carriage and means to mount the device and carriage to the frame of the machine of the present invention, like mounting ring  13  of FIG.  1 . The carriage brings the heating device into proximity with the exposed portion of the sleeve. 
     In FIG. 13 carriage  111  has a frame or housing  113  which provides a top surface  115  for securing by brackets  117  a heating device  119  behind a sleeve cooling bushing  121  and an interior cavity  123 , under top surface  115 , for mounting or locating a means to impart motion to carriage  111 , like an air cylinder  125 . Carriage  111  is pneumatically driven by an air cylinder  125 , supplied with air by lines  127 . Carriage  111  is slidably mounted on rods  129  which are linear guide means. Each rod  129  is secured by a bracket  131  at each end of rod  129  to mounting plate  133 . 
     Preheat station (B) operates as follows: when a sleeve loaded and positioned on mandrel  87  is aligned with the center axis of cooling bushing  121  and heating device  119  of preheat station (B), carriage  111  advances along rods  129  to bring heating device  119  in proximity to the sleeve. Carriage  111  may move by any conventional method, namely a servo or indexing motor, a pneumatic, hydraulic, electric or magnetic actuator. 
     As carriage  111  advances, the exposed portion of the sleeve enters and passes through an orifice  135  in cooling bushing  121 . The exposed portion of the sleeve is partially inserted into heating device  119 . Heating probe  137  located in heating device  119  extends into the exposed portion of the sleeve. The interior surface of the exposed portion is then heated by hot air exiting small openings  139 , shown in FIG. 14, at the end of heating probe  137 . Air is supplied to heating device  119  by supply line  141 . Cooling bushing  121 , which may be cooled by a water jacket (not shown), substantially prevents the heat applied to the exposed end of the sleeve from spreading to the remainder of the sleeve. 
     Carriage  111  retracts by the action of air cylinder  125  to its original position, out of the path of motion of mandrel  87 , after a preselected period-of time. The time of heating depends on the material and the thickness of the thermoplastic to be heated. After carriage  111  retracts, the preheating step is completed. 
     Any means for heating an air flow in heating device  119  is satisfactory. Typically, heating device  119  is made of a metal which has good electrical resistance. In this embodiment, heating device  119  is itself heated so that air flowing through it is raised to the desired temperature. The air flow rate, the temperature of the heating element and time of heating can all be controlled by a PLC device. 
     Preheat station (B) is made of light weight durable materials. For example, cooling bushing  121  may be made of aluminum and heating element  119  and heating probe  137  may be made Qf stainless steel. Aluminum provides a durable and light weight material for housing  113  of carriage  111 . Rods  129  receive a lot of wear so they need to be made of a durable and hard material. Ideally, rods  129  can be made from cold rolled steel. 
     After the heating at preheat station (B), indexing table  89  advances one position so that the heated exposed end of the sleeve is now adjacent heat station (C). 
     (C) Heat station 
     FIGS. 13 and 14 also illustrate the preferred heat station (C) of this embodiment. Preferably heat station (C) is physically the same as preheat station (B). Heat station (C) operates in the same manner as preheat station (B) and heats the preheated exposed portion of the sleeve above the glass transition temperature. Depending on the heating time of preheat station (B), the carriage  111  of heat station (C) (FIG. 13) may move at the same rate or a different rate than carriage  111  of preheat station (B). 
     As the inside surface of the sleeve is heated close to the glass transition temperature, in this embodiment, the inside surface melts faster than the outside surface. The heating of a longitudinally stretched and extruded thermoplastic sleeve results in die swelling. Die swelling is the shrinking and thickening of a thermoplastic sleeve because the plastic memory of the sleeve wants to return the sleeve to its original larger shape, the shape of the die used in the extrusion process. The molten preform mass at the heated end of the sleeve thickens and is ideal for molding a head onto the end of the sleeve. 
     After the heating is completed carriage  111  of heat station (C) retracts out of the path of mandrel  87 . Indexing table  89  advances one position so that the hollow thermoplastic sleeve is adjacent mold station (D) downstream from heat station (C). 
     (D) Mold Station 
     FIGS. 15 and 16 illustrate preferred mold station (D), located downstream from heat station (C). Mold station (D) forms a head from the heated thermoplastic mass at the end of the sleeve previously heated in preheat station (B) and heat station (C). Mold station (D) has a mold die secured to a movable carriage and means to mount the device and carriage to the frame of the machine of the present invention, like mounting ring  13  of FIG.  1 . The carriage brings the mold die into contact with the exposed portion of the sleeve. 
     In FIG. 15 carriage  143  has a frame or housing  145  which provides a top surface  147  for securing a mold die  149  and an interior cavity  151 , under top surface  147 , for mounting or locating a means to impart motion to carriage  143 , like an air cylinder  153 . Carriage  143  is pneumatically driven by an air cylinder  153 , supplied with air by lines  155 . Carriage  143  is slidably mounted on rods  157  which are linear guide means. Each rod  157  is secured by a bracket  159  at each end of rod  157  to mounting plate  161 . 
     In this embodiment, mold die  149 , secured by brackets  163  to top surface  147  of carriage  143  and preferably made of aluminum or steel, has four components: a mold bushing  165 , a mold bushing plate  167 , a thread insert plate  169  and an orifice pin bushing  171 , as illustrated in cross-section in FIG.  16 . Mold bushing  165  forms the entrance to mold die  149 . Mold bushing  165  guides the heated sleeve into mold die  149 . The subsequent components, mold bushing plate  167 , thread insert plate  169  and orifice pin bushing  171  shape portions of a head on the end of the sleeve. A die with four components, like mold die  149 , allows a manufacturer to selectively shape the head of a sleeve with specific members to comprise mold die  149 . Orifice pin bushing  171  contains a spike (not shown) located in the center to form an orifice in the headed end of the thermoplastic tube. 
     Alternatively the mold die may be a one-piece die which does not open. Such a die would be useful for forming a simple head on a sleeve. The die may take the form of a simple one-piece member with a concave face to shape the sleeve end portion of the molten thermoplastic into a closed end of a tube. But if threads or undercuts are desired on the head, then at least a portion of the mold die, for example, must open to allow the release of the tube once the head has been formed. Simple open and close pneumatic dies, like an air cylinder split die, are available for this purpose. 
     The time and pressure of the molding step are important. The time for molding should be limited to the time necessary to form a head from the heated thermoplastic. If a head is not removed from a die once formed, it may stick to the inner surface of the die. If the mold pressure is too great, the thermoplastic may be pressed out of the mold. If the mold pressure is weak, a head may be poorly formed and uneven. The time of molding and pressure used will depend on the thermoplastic and its thickness. Time and pressure may be controlled by a PLC device. 
     After a head is formed, indexing table  89  indexes to the next station located downstream, treat station (E). 
     3) Decorating Thermoplastic Tubes 
     As previously mentioned there are a variety of ways to decorate the outside surface of a thermoplastic sleeve or thermoplastic tube if it has been so formed. The decoration step may precede the head forming step. In this embodiment however, decoration occurs after forming a head on the sleeve. 
     Decorating may occur by a variety of different means and methods. For example, a label may be applied to a tube by a label dispensing device. A tube may be marked with an indicia, including an individual indicia or a printed graphic. Many printing methods are know for printing indicia on tubes, such as offset printing, screen printing, foil printing, inkjet printing, letter printing, computer printing, etc. A tube may also be decorated by being coated, heat embossed or etched. 
     The outside surface of a thermoplastic tube or sleeve is typically treated prior to decorating by printing, coating or labelling so that the outer surface is more receptive or adherent to a printed graphic. The type of treatment step will depend on the decoration step that follows. 
     The manufacturing stations used to decorate the thermoplastic article on machine  85  of the second embodiment include: treat station (E) for pretreating the thermoplastic article, label station (F), print station (G), coat station (I) and cure stations (H) and (J). 
     (E) Treat Station 
     Often before a printed indicia or label may be applied to thermoplastic polymer, the polymer must be treated to receive the printed indicia or label. There are a variety of ways to surface treat thermoplastic, such as, flame treatment, corona treatment, ionic treatment, electrical treatment, heat treatment or chemical treatment. 
     Corona treating is common and works as follows: A corona treating system is like a capacitor. High voltage is applied to an electrode. Between the electrode and a “ground” is a dielectric, comprised of the thermoplastic tube and air. The voltage buildup on the electrode ionizes the air in the electrode, creating the highly energized corona. This excites the air molecules, reforming them into a variety of free radicals, which then bombard the tube surface, increasing its polarity by distributing free bond sites across it. This makes the surface more receptive to printed indicia. 
     Flame treatment is common for bottles, tubing, and automotive parts. Like corona, it induces an ionized airstream, which alters the surface as it impinges upon it. Flame treatment is accomplished by burning an ultra-lean gas mixture, whose excess oxygen is rendered reactive by high temperatures. 
     Treatment, specifically corona and flame treatment, alter a polymer&#39;s surface chemistry. The presence of carbonyl and hydroxyl groups, which are absent on an untreated surfaces, enhances wetability, allowing inks, coatings, and adhesives to flow out and coat uniformly. 
     FIG. 17 illustrates treat station (E). Treat station (E) comprises treatment device  173 , having supply line  175 , which provides the means for treating a thermoplastic tube located on mandrel  87 . In this embodiment, treatment device  173  is a corona treater. Treatment device  173  is secured to mounting bracket  177  that is adjustable relative to the location of mandrel  87 , much like an X-Y positioning table. Mounting bracket  177  has a X-axis adjustment rod  179  and a Y-axis adjustment rod  181 . Mounting bracket  177  is further mounted on the frame of the machine. 
     (F) Label Station 
     In this embodiment, the first decorating station downstream treat station (E) is label station (F). Label station (F) has a device for applying adhesive labels to the exterior surface of thermoplastic tubes and a means to mount the device to the frame (not shown) of the machine. A device suitable for applying labels to thermoplastic tubes may be used in label station (F). The indigo or zicon processes are preferable for labeling on thermoplastic tubes. 
     FIG. 18 illustrates preferred label station (F). Label station (F) has a label dispenser  183 , which dispenses sheet  185 , having labels thereon, which travels through a series of directional cylinders  187   a, b, c, d, e , and  f , which are label guides, to a final label intake roll  189 . Sheet  185  exits dispensing device  183 , travels to directional cylinder  187   e , which is in close proximity with a tube on mandrel  87 . When sheet  185  passes directional cylinder  187   e , an individual label is pinched off sheet  185  and pressed against a tube. The empty label sheet  185  is rewound on label intake roll  189 . 
     It is important that the labels are applied to tubes and not to mandrel  87 . To avoid such error, a sensor can be included in label station (F) to detect whether a tube is located on mandrel  87 . 
     Label station (F) is a labeling device housed in a frame  191  which is mounted on a frame or mounting ring, like mounting ring  13  as shown in FIG. 1, of the machine of the present invention. 
     (G) Print Station 
     Instead of applying an adhesive label to the exterior of the thermoplastic tube, a printed indicia may be applied to the tube. FIG. 19 illustrates a preferred inkjet printer of print station (G) having four printer head cartridges  193   a, b, c  and  d  disposed on a bar  195  which is secured to mounting bracket  197 , which is further mounted to the frame (not shown) of the machine of the present invention. Printer head cartridges  193   a, b, c  and  d  are connected to a plurality of ink supply and control lines  199 . 
     The inkjet printer of print station (G) is preferably controlled by a PLC device. A PLC device gives a manufacturer the ability to mark each tube with an individual indicia or the same printed graphic. A PLC device can control the ink flow and pattern of printing from the printer head cartridges of an inkjet printer. 
     A PLC device may be programmed to print individual indicia, like a unique serial number on each tube. Thus an inkjet printer is advantageous because of the ability to quickly and automatically alter, modify, and change printed indicia on thermoplastic tubes. 
     After a printed indicia is applied to the tube, the printing must be cured. 
     (H) Cure Station 
     Cure station (H), located downstream from print station (G), cures the printed indicia applied to the thermoplastic tube. FIG. 20 illustrates preferred cure station (H), having a curing unit  201  connected to a supply and control line  203 . Curing unit  201  is secured to mounting bracket  205  that is adjustable relative to the location of mandrel  87 . Adjustment may be done manually by a X-axis adjustment rod  207  and a Y-axis adjustment rod  209 . Alternatively the adjustment could be controlled by a PLC device. Mounting bracket  205  is secured to the mounting ring or equivalent of the frame of the machine of the present invention. 
     Curing unit  201  may cure the printed graphic by any known means such as heat, infrared light, hot air, or ultra violet light. In the embodiment illustrated in FIG. 20, curing unit  201  is a hot air curing unit where hot air is discharged from curing unit  201  onto the tube. 
     Curing unit  201  may be left on continuously. Or, like other stations in the manufacturing process, it may be computer controlled so that the curing process may be controlled with more precision. Because curing unit  201  may be a UV light emitting unit, safety shutters (not shown) may be provided to shield operators from the exposure of UV light. 
     (I) Coat Station 
     The third decorating station on machine  85  is coat station (I) which is a station for applying a coat of material to a tube. This may be an alternative to decorating via label station (F) or print station (G). Coat station (I) may also be used in conjunction with label station (F) and print station (G). FIG. 21 illustrates preferred coat station (I). Coat station (I) has two coater rollers  211   a  and  b  in front of a doctor blade  213 , all of which are supported on a mounting bracket  215  further mounted on the frame of the machine of the present invention. The two coater rollers  211   a  and  b  contact a tube on mandrel  87  and apply a chemical coat directly onto the tube. The chemical coat is applied to coater rollers  211   a  and  b  by doctor blade  213 . Doctor blade is connected to a chemical supply line (not shown). After a chemical is applied on the tube the chemical coating is typically cured. 
     (J) Cure Station 
     Final cure station (J) is the same as cure station (H) illustrated in FIG.  20 . Final cure station (J) is for the purpose of curing coating or indicia on tubes and may cure by the same means as cure station (H). In the present embodiment, final cure station (J) is a heat cure station having a curing unit  201  which is a hot air curing unit where hot air is discharged from curing unit  201  onto the tube. 
     After decorating, the thermoplastic tube may advance through a variety of different finishing stations for finishing the decorated tube. The number, arrangement and variety of finishing stations will depend on the desired tube to be produced. 
     4) Finishing Thermoplastic Tubes 
     Besides forming a head on a thermoplastic sleeve and decorating the same, there are many different process steps that may be performed for finishing the thermoplastic tube. For example, the orifice on the formed head may be sealed with a protective foil, a closure means may be secured to the formed head and the closure may be torqued automatically for proper tightness. 
     Machine  85  of FIG. 11 includes the following finishing stations: tab seal (K), cap (L) and a torque station (M). 
     (K) Tab Seal Station 
     FIG. 22 illustrates a tab seal station of the preferred embodiment. A tab sealer  217  is housed in a frame  219  comprising a mounting bracket  221  on which tab sealer  217  rests connected to a mounting plate  223  located on either side of the mounting bracket  221 . This structure can support the remainder of the device as necessary to place a small protective seal, made of foil or other material, over the orifice of headed thermoplastic tubes. 
     A protective tab seal is added to tubes by means of a applicator device which, in the preferred embodiment is a tab seal punch  225  which cuts and places appropriately sized tab seal material  227  over the orifice of a thermoplastic tube. 
     As shown in FIG. 22 tab seal punch  225  is driven by an air cylinder  229  supplied with air by air and control lines  231 . The tab seal punch  225  slidably moves, by the action of the air cylinder  229  through a tab seal die  235  on a tab seal mounting plate  237  and contacts tab seal material  227  on the other side of the tab seal die  235 . This tab seal material  227  is supplied from a tab seal stock roller  239 . Tab seal material  227  unwinds from stock roller  239 , passes tab seal punch  225  and is taken up by tab seal foil intake roller  241 . 
     By the pneumatic action of the tab seal punch rod  225  through the tab seal die  235 , small portions of tab seal material  227  are cut from the ribbon of tab seal material  227  and brought into contact with the headed end of a thermoplastic tube whereby the tab seal foil is cut and secured. 
     The tab seal station (K) illustrated in FIG. 22, operates continuously as long as it is supplied with tab seal foil stock. To possibly accommodate longer continuous manufacturing periods, a tab seal foil stock roller (not shown) may be mounted on top of the frame of the machine such that tab seal foil stock ribbon is wound from the foil stock roller down in front of the tab seal die to supply foil stock to the tab seal station. This ribbon may be wound under the die and back up to a larger intake roll (not shown) mounted elsewhere on the manufacturing station. Therefore this allows for the possibility of much larger stock and intake rolls to accommodate larger manufacturing times. 
     (L) Cap Station 
     Cap station (L) is located downstream from tab seal station (K). This station provides a means for adding a closure or cap, typically made of plastic, to the headed end of a tube. The cap may be either snapped onto the end of the thermoplastic tube or screwed on if the head has screw threads. 
     Preferable capping station (L), as shown in FIG. 23, comprises a cap applicator  243  and brackets  245  for mounting cap applicator  243  to the frame of the machine, like mounting ring  13  of FIG.  1 . Cap applicator  243  is a device which secures a cap or closure to the headed end of tubes. Each cap is individually placed on the headed thermoplastic tube by cap applicator  243 . If the cap must be screwed on to the head of the thermoplastic tube, then cap applicator  243  has a screw type mechanism for rotating caps. Cap applicator  243  is continuously supplied with caps by a supply line (not shown). Cap applicator  243  is connected to power supply and control line  247 . 
     After a cap is applied to the headed thermoplastic tube, the torque of the cap is typically adjusted. 
     (M) Torque Station 
     Torque station (M) is located downstream from cap station (L). Torque station (M) is provided for adjusting the torque of the closure applied to the head of the thermoplastic tube in cap station (L). 
     As illustrated in FIG. 24, torque station (M) comprises a cap torque chucking device  249  and brackets  251  for mounting torque chucking device  249  to the frame of the machine, like mounting ring  13  of FIG.  1 . Chucking device  249  adjusts the torque of each cap on each tube. It can accomplish this device by a mechanical screw means. 
     Torque station (M) is connected to power supply and control line  253 . 
     5) Unloading Thermoplastic Tubes 
     Manufacturing on a machine of the present invention ends with unloading tubes from mandrels  87 . To unload thermoplastic tubes off mandrels, the following devices, each comprising an unload device or stripper, may be used: a pneumatic stripper, a stripper driven by a cam driver, an advancing and retracting linear actuator stripper, a crank motion stripper or a servo-motor driven stripper. The preferred unloading device is a pull rod stripper driven by an air cylinder which works similarly to push rod  93  of load station (A). 
     (N) Unload Station 
     The final station of machine  85  is illustrated in FIG. 25 as unload station (N). Unload station (N) is downstream torque station (M) and next to the first station in the manufacturing path load station (A). 
     Pneumatic stripper  255 , with stripper plate  257 , is driven back and forth along guide arm  259  by air cylinder  261 , supplied with air by air lines  263 , positioned behind guide arm  259  on a mounting bracket  265 . Mounting bracket  265  is further mounted on a mounting plate, like mounting plate  103  of FIG. 12, which is attached to a mounting ring or equivalent, like ring  13  of FIG.  1 . Stripper  255  removes the finished thermoplastic tubes from mandrel  87  by stripper plate  257  attached to the end of stripper  255 . 
     Unload station (N) operates as follows: a stripper plate  257  slides back and forth in contact with mandrel  87  unloading any tube on mandrel  87 . Once the thermoplastic tube has been removed, stripper  255  and stripper plate  257  return to their original position. 
     All of the 14 stations described above operate to form one embodiment of a complete manufacturing process for decorated capped and torqued thermoplastic tubes. 
     6) Additions and Alternates 
     The machine of the present invention is intended to be flexible to that manufacturing stations of various types, numbers and arrangements may be configured on the machine so that a large variety of tubes can be manufactured. In addition to the stations and methods described above, many other manufacturing stations and process steps are possible. Described below are other methods and devices for the machine of the present invention, without intending to be limiting. 
     Forming a head a sleeve, for example, may be done by a variety of different methods. For example, a previously formed head may be joined with a thermoplastic sleeve by heat welding or sonic welding the sleeve and the head together. Or a head may be formed from the end of the thermoplastic sleeve by the process disclosed in U.S. Pat. No. 5,069,856, assigned to the assignee of the present invention and the process of which is incorporated herein. Further a head may be formed by injection blow molding or blow molding a head directly onto a sleeve loaded onto a mandrel on the indexing device. 
     Still further a head may be molded in a reusable closure means or cap. An example of molding in a reusable closure means is described co-pending application “Method of Forming a Headed Thermoplastic Tube with a Reusable Closure”, Ser. No. 09/199,692, which is now U.S. Pat. No. 6,129,880 assigned to the assignee of the present invention and incorporated by reference herein. Therefore, depending on the finished product desired any number of different methods may be used to form a head on the end of thermoplastic sleeve. 
     An example of forming a head in a in a reusable closure means is as follows: A method of forming a tube from an thermoplastic extruded, stretched sleeve is provided by positioning a sleeve over a forming mandrel with an exposed portion of the sleeve extending beyond a head forming end of the mandrel. The inner wall surface of the exposed portion of the thermoplastic sleeve is heated to a temperature above the glass transition temperature of the thermoplastic material to render the inner surface area molten, while maintaining the outer surface of the sleeve below the glass transition temperature so as to provide support for the exposed portion of the sleeve and retain the cylindrical shape thereof. The heated exposed portion is then shaped into a conical shape, such as by directing hot air against the outer surface thereof. Pressure is then applied to the conical shaped exposed portion of the thermoplastic extruded sleeve by contacting the exposed portion with a reusable closure means to form a headed thermoplastic tube. The pressure applied to the conical shaped exposed end portion forces the same into a reusable closure means for the tube held in place by a holding or gripping member. 
     The reusable closure means used in this method functions as a mold for the neck or a mold for both the shoulder and neck when forming a head on the thermoplastic sleeve and a reusable cap for the finished thermoplastic tube. The reusable closure means is made of a material incompatible with the thermoplastic sleeve material such that when the molten end of the thermoplastic sleeve is pressed into the reusable closure means, the reusable closure means does not melt or stick to the molten preform. 
     Preferably, the reusable closure means has an orifice-forming spike located in the center of internal cavity. The orifice-forming spike is a protrusion which prohibits the complete closure, except for a small orifice, of the closed end when the conical shaped portion is being shaped in the molding process. 
     This method has several advantages. First, forming a head on the thermoplastic sleeve and capping the head with a closure means is performed in a single step. Secondly, forming a head in a closure means ensures a perfect fit. Thirdly, there is no die wear by forming a head in a reusable closure means. The reusable closure means serves as the die and it is replaced for every sleeve. Additionally, the method of the present invention is advantageous for forming an undercut on the head of the thermoplastic tube. An undercut is a groove, rib or niche created by a corresponding shape in a mold. If threads or undercuts are formed by the use of a die, then the die must be opened before the tube head is removed in order to provide clearance for the formed threads or grooves. However by forming the headed end of a thermoplastic tube in a reusable closure means, an open and close die need not be used in order to remove the capped tube. Additionally, unique features and shapes may be molded onto the thermoplastic tube depending on the shape of the mold, i.e) the reusable closure means. 
     The-method is shown in detail in FIGS. 48-50. The forming of a head on a thermoplastic tube  401  is carried out by applying pressure to the conical shaped portion which includes the mass of moldable thermoplastic material. Sufficient force or pressure may be applied by use of the head forming end  403  of the forming mandrel  405  and a reusable closure means  407 . Reusable closure means  407  has an internal cavity  409  formed by a bottom wall  411  and a side wall  413 , as illustrated clearly in FIG. 50, and held in place by die member  415 , shown in FIG.  48 . 
     Die member  415  has an internal cavity the size of the exterior surface of the reusable closure, means  407  in order to firmly hold the reusable closure means  407  during the forming of a head on the thermoplastic sleeve  401 . Positioned on top of die member  415 , so that an internal cavity is aligned with the internal cavity of die member  415 , is shoulder forming member  417 . Shoulder forming member  417  is shaped to form the shoulder portion  419  of the headed thermoplastic tube  401 . Shoulder forming member  417  may have an angled portion  421  which acts to guide the insertion of thermoplastic sleeve  401  into shoulder forming member  417  and die member  415 . Both shoulder forming member  417  and die member  415  are held in place by upper holding support  423  and lower holding support  425 . 
     The forming mandrel  405  is illustrated by an arrow in FIG. 48 as being able to insert into shoulder forming member  417  and reusable closure means  407  to form the conical shaped portion of thermoplastic sleeve  401  into a head having shoulder portion  419  and neck portion  427 . 
     Preferably, reusable closure means  407  has an orifice-forming spike  429  located in the center of internal cavity  409 . Orifice-forming spike  429  is a protrusion which prohibits the complete closure, except for a small orifice, of the end of the thermoplastic tube  401 . 
     FIG. 49 illustrates the formed headed thermoplastic tube  401  having reusable closure means  407  after removal from die member  415  and still retained on the forming mandrel  405 . 
     FIG. 50 is an enlargement of the circled portion of thermoplastic tube  401  of FIG.  49 . FIG. 7 shows a threaded fit of the reusable closure means  407  created by a continuous concave groove  431  having a “screw” or spiral path in the interior surface of the reusable closure means  407 . Inside groove  431  is formed a reciprocating continuous rib  433  during the formation of neck portion  427  of thermoplastic tube  401 . The cooperation of groove  431  and rib  433  creates a “threaded” fit so that the reusable closure means  407  may be screwed back on neck portion  427  once removed. Alternatively, groove  431  may have the shape of a non-continuous spiraling groove. 
     Yet a further method for forming a head on a tube involves rotating a sleeve while heating it. An example of this method is described co-pending application “Method of Forming a Headed Thermoplastic Tube”, Ser. No. 09/199,695 which is now U.S. Pat. No. 6,136,247 assigned to the assignee of the present invention and incorporated by reference herein. A thermoplastic extruded, longitudinally stretched sleeve is positioned over a forming mandrel with an exposed portion of the sleeve extending beyond a head forming end of the mandrel. The mandrel is then rotated while the sleeve is heated. The rotation provides for even heat distribution at the location where the heat is applied. The rotation of the sleeve is stopped and pressure is then applied to the conical-shaped, exposed portion of the thermoplastic, extruded sleeve by contacting the exposed portion with a molding die to form a headed thermoplastic tube. 
     Rotating or spinning the sleeve has the advantage of lessening the effect of gravity on the thermoplastic molten preform of the exposed portion if the mandrel is horizontal. For example, especially for larger diameter sleeves of a size such as a, 2 inch, 1½ inch, 1⅜ inch and 1{fraction (3/16)} inch diameter, the centrifugal forces of the rotation will lessen the effect of the exposed portion to sag due to gravity. Centrifugal forces will pull the molten material outward resulting in a bullet-shaped preform  435  as in FIG.  51 . Gravitational force can be negated or limited by the centrifugal force applied to the thermoplastic sleeve. Rotating the sleeve constantly changes the direction of forces acting on any specific section of the sleeve thereby cancelling the effect of gravity on that section and thus the entire sleeve. 
     Besides control over the preform mass, rotating provides even heat distribution in the exposed portion. An even temperature distribution and controlled preform shape are good manufacturing conditions for consistently creating high quality molded heads without overlap or flash defects. Previously these defects were harder to control. The rotation step may be used with thermoplastic sleeves of all sizes, such as ½, ⅝, ¾, ⅞, 1, 1{fraction (3/16)}, 1⅜, 1½ and 2 inches. 
     Furthermore, because of even heat distribution, higher temperatures may be used without burning the plastic of the sleeve. The use of higher temperatures decreases the heating time necessary to reach the glass transition temperature in exposed end of the sleeve. 
     Again, control is provided by rotating or spinning the sleeve while heating the inside to get a molten preform with uniform heat distribution. Spinning gives the manufacturer the ability to work with larger diameter tubes without the disadvantage of the tube collapsing on itself because of the stresses on the larger diameter tubes. This control is cannot be achieved by the methods of the prior art. 
     The details of the process are illustrated in FIG.  52 . The hot fluid heats the inner wall surface  437  of the exposed portion  439  to a temperature above the glass transition temperature of the thermoplastic material and melts inner wall surface  437 , while an outer surface  441  of the exposed portion  439  provides sufficient support to maintain the exposed portion  439  as a substantially cylindrical shape. When sufficient heat has been applied to the inner wall surface  437  of the exposed portion  439  to melt the same, the hot air nozzle  443  is removed from the exposed portion and the heated exposed portion  439  is shaped into a bullet-shape  435 , such as by the application of additional heat of further hot fluid, indicated by arrows in FIG.  53 . Additional hot fluid may be, for example, hot air from external hot air nozzles  445 , which heats the outer surface  441  of the exposed portion  439  of the thermoplastic extruded, stretched sleeve  401 . 
     Outer surface  441  is heated to a temperature above the glass transition temperature of the thermoplastic material whereby it melts rendering outer surface  441  into a moldable state. 
     While heating of the outer surface  441  by a hot fluid may be used to form the conical shape  435 , it is also possible to continue the heating of the inner wall surface  437  of the exposed portion  439  until the outer surface  441  no longer maintains the substantially cylindrical shape, such that the conical shape  435  results in the exposed portion  439 . Forming mandrel  405  may be rotated continuously during the entire heating process, as indicated by the arrows in FIGS. 52 and 53. Because the thermoplastic extruded sleeve  401  is a stretched material, when the exposed portion  439  is heated above the glass transition temperature, the plastic memory responds and the exposed portion  439  swells to a thickness of or. substantially the thickness of the tubular extrusion thickness,.generally about two to three times the wall thickness of the thermoplastic extruded, stretched, sleeve  401 . The hot exposed portion  439 , when above the glass transition temperature in addition to swelling in wall thickness, shrinks in the direction of the axis of the sleeve and provides a mass of moldable thermoplastic material for the forming of a head. 
     After shaping of the heated exposed portion  439  of the thermoplastic extruded stretched, sleeve  401  into the conical shape  435 , the rotation of forming mandrel  405  is stopped and pressure is applied on the exposed portion  439  through the head forming end  403  of the forming mandrel  405  to form a headed thermoplastic tube  401 . 
     An alternate way to form a head is to weld a preformed head onto a sleeve by high frequency sound. Sonic weld station, illustrated in FIG. 26, may be substituted for preheat (B), heat (C) and mold (D) stations of machine  85  as an alternative station for forming a head on a sleeve. 
     FIG. 26 illustrates a preferred sonic welding station for welding by high frequency sound, a preformed head to a thermoplastic sleeve. Sonic weld station has a sonic welder attached to a movable carriage and means to mount the device and carriage to the frame of the machine of the present invention, like mounting ring  13  of FIG.  1 . The carriage brings the sonic welder into proximity with a sleeve. 
     In FIG. 26 carriage  267  has a frame or housing  269  which provides a top surface  271  for securing sonic welder  273  and an interior cavity  275 , under top surface  271 , for mounting or locating a means to impart motion to carriage  267 , like an air cylinder  277 . Carriage  267  is pneumatically driven by an air cylinder  277 , supplied with air by lines  279 . Carriage  267  is slidably mounted on rods  281  which are linear guide means. Each rod  281  is secured by a bracket  283  at each end to mounting plate  285 . 
     The sonic weld station operates as follows: when a sleeve loaded and positioned on mandrel  87  of machine  85 , for example, is aligned with sonic welder  273 , carriage  267  advances along rods  281  to bring sonic welder  273  in proximity to the sleeve. As carriage  267  advances, an exposed portion of the sleeve enters and passes into sonic welder  273  which welds a preformed head to the sleeve by means of high frequency sound. 
     Sonic welder  273  is connected to supply and control line  287  which supplies the input necessary for sonic welder  273  to operate. 
     Sonic welder  273  is mounted in housing  289  which is attached to top surface  271  of carriage  267 . Carriage  267  retracts by the action of air cylinder  277  to its original position, out of the path of motion of mandrel  87 , after a preselected period of time. The result of the manufacturing step is that a preformed head is welded onto a sleeve to form a tube. 
     Another method of forming tubes according to the present invention is by forming tubes from thermoplastic sheets. Cut sheets may be loaded onto a machine of the present invention and subsequently formed into sleeves which are later formed into tubes. The method for forming tubes comprises: loading a flat sheet onto a supporting means on the indexing device; forming the flat sheet on the supporting means into the form of a sleeve; and welding opposed sheet edges together to form a closed sheet. The closed sheet is then formed into a tube. 
     Cut sheets can be supplied to a means for loading and wrapping the sheets around a mandrel. The sonic welding station is appropriate for welding the edges of the sheet together to form a seam. The carriage  267  of the sonic weld station described above (FIG. 26) can advance the sonic welder  273  along the length of a sheet wrapped around a mandrel in order to selectively weld the joined edges of the sheet together. Alternatively the edges of a sheet could be heat welded together or adhered by any other means. The machine of the present invention is also useful for completing the manufacturing of tubes if, for example, the sleeves have been partially processed at another location. Preprinted sleeves may be loaded onto a machine of the present invention and the manufacturing of tubes may be completed by forming a head on the sleeves and performing any desired finishing step like, tab sealing, capping or torquing. 
     7) Large Scale Manufacturing 
     The machines of the present invention may be arranged into small groups. When arranged into small groups or “production cells,” space, labor and raw material input can be saved. One production cell typically contains six machines each of which can manufacture headed, sealed, capped and decorated tubes from blank thermoplastic sleeves. A single cell has a total output equivalent to a single conventional process line. 
     A manufacturing and packing plant using machines of the of the present invention is an efficient arrangement of a plurality of production cells connected by a common transportation line. The efficient arrangement of cells leads to further decreases in labor necessary to operate a number of production cells. An example of the preferred manufacturing plant is described in co-pending application “Plant for Manufacturing and Packing Thermoplastic Tubes”, Ser. No. 09/199,617 which is now U.S. Pat. No. 6,047,525, assigned to the assignee of the present application and incorporated by reference herein. 
     IV. Manufacturing with a Programmable Logic Controller 
     A PLC device may be added to the machine of the present invention for the purpose of controlling the entire machine including the various manufacturing stations. In conventional process lines some of the manufacturing equipment is PLC controlled. However machine feedback control to control all aspects of a manufacturing step, product quality control and product feedback control and total mechanical control over sleeves and tubes have not been feasible. Such PLC control is almost impossible in conventional processing lines because large processing lines handle several hundred thermoplastic articles at a time and there is no systematic method for keeping track of individual articles and controlling the same on the conventional machines. 
     FIG. 1 illustrates one embodiment of a machine of the present invention, with each manufacturing station connected to a PLC device, as indicated by the dashed lines. The PLC device can perform a variety of functions: A PLC device may be employed to control, by turning on or turning off, each manufacturing station along a manufacturing path. A PLC device can control the inputs needed for each manufacturing station. For example, a PLC device can control the heating temperature of the preheat and heat stations. The PLC can control the speed of each manufacturing station and the speed of the entire manufacturing machine. 
     Process control for the machine of the present invention involves controlling the operation of individual manufacturing stations alone or in combination with other manufacturing stations around the closed manufacturing path. The operation of the manufacturing stations may be based on information gathered from sensors obtaining information about the operation of each manufacturing station itself, sensors obtaining information about the quality of the thermoplastic tubes produced, or information obtained from both the operation of each of the manufacturing stations and the quality of the thermoplastic tubes produced. 
     Examples of the sensors that may used are listed below in Table I: 
     
       
         
           
               
               
               
               
             
               
                   
                 TABLE I 
               
               
                   
                   
               
               
                   
                 SENSOR 
                 TYPE 
                 MEASUREMENT 
               
               
                   
                   
               
             
            
               
                   
               
            
           
           
               
               
               
               
            
               
                 1. 
                 Load sensor 
                 Electric Eye 
                 Confirm Load 
               
               
                 2. 
                 Preheater Air Flow 
                 Flow Meter 
                 Air Flow Rate 
               
               
                 3. 
                 Preheater Temperature 
                 Thermocouple 
                 Air Temperature 
               
               
                 4. 
                 Sleeve Temperature 
                 Infrared Sensor 
                 Sleeve Temperature 
               
               
                 5. 
                 Heater Air Flow 
                 Flow Meter 
                 Air Flow Rate 
               
               
                 6. 
                 Heater Temperature 
                 Thermocouple 
                 Air Temperature 
               
               
                 7. 
                 Sleeve Temperature 
                 Infrared Sensor 
                 Sleeve Temperature 
               
               
                 8. 
                 Mold Temperature 
                 Thermocouple 
                 Cooling Water Temperature 
               
               
                 9. 
                 Mold Flowmeter 
                 Flow Meter 
                 Cooling Water Flow Rate 
               
               
                 10. 
                 Treater Confirmation 
                 Electric Eye 
                 Confirm Corona Arc 
               
               
                 11. 
                 Treater Amperage 
                 Ammeter 
                 Treatment Level/ 
               
               
                   
                   
                   
                 Pinhole Detection 
               
               
                 12. 
                 LabelSensor 
                 Labeler Controller 
                 Confirm Label Application 
               
               
                 13. 
                 Printer 
                 Print Controller 
                 Confirm Print Application 
               
               
                 14. 
                 Cure Sensors 
                 Voltmeter 
                 Cure Unit Voltage 
               
               
                   
                   
                 Ammeter 
                 Cure Unit Amperage 
               
               
                   
                   
                 Thermocouple 
                 Cure Unit Temperature 
               
               
                 15. 
                 Inspection System 
                 Vision System 
                 Confirm Heading &amp; Print 
               
               
                   
                   
                 (Camera) 
                 Quality 
               
               
                 16. 
                 Coating Sensor 
                 Level Sensor 
                 Confirm Coating Pretense 
               
               
                 17. 
                 Cure Sensors 
                 Voltmeter 
                 Cure Unit Voltage 
               
               
                   
                   
                 Ammeter 
                 Cure Unit Amperage 
               
               
                   
                   
                 Thermocouple 
                 Cure Unit Temperature 
               
               
                 18. 
                 Inspection System 
                 Vision System 
                 Confirm Heading, Print, 
               
               
                   
                   
                 (Camera) 
                 Coating Quality 
               
               
                 19. 
                 Tab Seal 
                 Thermocouple 
                 Punch Temperature 
               
               
                   
                   
                 Electric Eye 
                 Tab Seal Pretense 
               
               
                 20. 
                 Inspection System 
                 Vision System 
                 Confirm Heading, Print, 
               
               
                   
                   
                 (Camera) 
                 Coat, &amp; Tab Seal Quality 
               
               
                 21. 
                 Capping 
                 Electric Eye 
                 Confirm Cap Pretense 
               
               
                 22. 
                 Torque 
                 Torque Meter 
                 Confirm Applied Torque 
               
               
                 23. 
                 Inspection System 
                 Vision System 
                 Confirm Heading, Print, 
               
               
                   
                   
                 (Camera) 
                 Coat, &amp; Capping Quality 
               
               
                 24. 
                 Eject 
                 Electric Eye 
                 Confirm Tube Removal 
               
               
                 25. 
                 Reject 
                 Electric Eye 
                 Confirm Tube Removal 
               
               
                   
               
            
           
         
       
     
     After gathering selected information from sensors in various locations around the closed manufacturing path the process control method would continue as follows: a signal would be generated corresponding to the selected information gathered from each of the manufacturing stations. The signals generated would be imputed into a PLC device and with the use of the signals, the operation of corresponding manufacturing stations would be controlled by the PLC device. 
     In a typical example of the control system, the PLC device will compute all of the “decisions” regarding the operation of the manufacturing machine based on information received from sensors on each manufacturing station. This provides the manufacturer with the opportunity to monitor the activities that occur at each station and identify any abnormalities in the product or process immediately. Defective products can identified instantly and downstream stations may be shut off to conserve process resources. The defective products can then be segregated at a reject station on the machine. 
     The PLC device in combination with the manufacturing stations, sensors and indexing table can collect, on a continuous basis, the type, degree and frequency of failures of the product or process. This can provide a profile of effectiveness of equipment and each process step. Reports can be generated about process and quality of the product. 
     Further process control would include establishing setpoints for controlling the operation of each manufacturing station and with the use of the generated signals, as previously mentioned, the operation of each manufacturing stations could be controlled within the established setpoints. Setpoints may be established automatically after the machine invention has reached steady state. The PLC device would automatically establish upper and lower boundary setpoints based on the operation of the machine at steady state over a period of time. Alternatively, the setpoints may be predetermined and simply programmed into the PLC device. 
     The signals generated from the sensors located on the manufacturing stations themselves or around the closed manufacturing path may be mechanical, electronic, optical, pneumatic, hydraulic or combinations thereof. Any type of signaling means may be used to communicate among the sensors and the PLC device. 
     Another method for controlling the thermoplastic tube manufacturing machine is the following: marking each tube with individual indicia; sensing selected information from tubes marked with individual indicia; generating a signal corresponding to each of manufacturing stations based on selected information; inputting signals to the PLC device; and with use of signals, controlling the operation of a corresponding manufacturing station with the PLC device. 
     Each thermoplastic tube may be marked with an individual indicia from a computer controlled printing device, like the inkjet printer of FIG. 19, which has the capability of uniquely marking each tube. Then select information may be gathered from the tubes marked with an individual indicia by a sensing means. Further signals may be generated based on the selected information gathered. The signals may be input into a PLC device and with the use of the signals, the operation of corresponding manufacturing stations may be controlled. This type of process control is the use of a feedback loop based on individually marked tubes to indicate to a PLC device to make or stop producing certain types, kinds, or varieties of tubes. 
     For example if 15,000 tubes of three different lots of 5,000 tubes per lot, all having the same diameter, are to be manufactured, then a feedback loop based on marked indicia on each tube would allow a manufacturer to manufacture the 15,000 tubes continuously without stopping the machinery. After 5,000 tubes of one type have been manufactured and an indicia on tube number 5,000 was identified by sensing means, like a vision camera, then a signal could be generated based on this indicia, and sent to a PLC device. With the use of this signal, the PLC device may then control the operation of the machine, with a subsequent command control signal, to change production, like changing the decoration step or the finishing steps, to manufacture the second lot of 5,000 tubes. The process could be repeated for the third lot of 5,000 tubes. By this feedback control method based on marking each tube with an individual indicia, a manufacturer may operate a machine of the present invention with zero down time. 
     FIG. 27 is a schematic representation a machine  291  of a third embodiment invention having indexing table  293 , 20 mandrels  295  mounted thereon and 20 manufacturing stations labelled (A) through (T), corresponding to each of 20 mandrels, all connected to PLC device  297 . Indexing table  293  rotates counterclockwise in this embodiment in response to indexer  299  (FIG.  28 ). The 20 stations and corresponding process steps of this embodiment are as follows: (A) load, (B) preheat, (C) heat, (D) mold, (E) treatment, (F) label, (G) print, (H) cure, (I) inspect, (J) coat, (K) cure, (L) inspect, (M) tab seal, (N) inspect, (O) cap, (P) torque, (Q) inspect, (R) unload, (S) reject and (T) confirmation. FIG. 28 is a perspective view of FIG. 27, showing only the main components of manufacturing stations (A) through (T). The manufacturing stations of machine  291  which are common to machine  85  of the second embodiment are physically the same as the manufacturing stations of machine  85 . 
     In addition to adding sensors to the stations of the manufacturing path illustrated in FIGS. 27 &amp; 28, additional stations have been added. Four inspection stations (I), (L), (N) and (Q) have been added at different locations along the closed manufacturing path. Product inspection may be performed by any known method. FIG. 29 illustrates any one of inspection stations (I), (L), (N), and (Q). An inspection station is typically a vision camera which has the ability to inspect product quality. The inspection station in FIG. 29 is illustrated as having a vision camera  301  receiving input and sending output signals to PLC device  297  (FIG. 27) through control and power line  303 . Vision camera  301  is mounted on a bracket  305  which may be adjustable and mounted on a frame or mounting ring of the machine, like mounting ring  13  of machine  1  in FIG.  1 . Inspection stations can identify, record, and monitor individual indicia on sleeves and tubes so marked. Indicia recorded by an inspection station can be stored in a PLC device. 
     Preferred rejection station (S) is illustrated in FIG.  31 . It is mechanically the same as unload station (N) of the embodiment on FIG.  25 . Pneumatic stripper  307 , with stripper plate  309 , is driven back and forth along guide arm  311  by air cylinder  313 , supplied with air by air lines  315 , positioned behind guide arm  311  on a mounting bracket  317 . Mounting bracket  317  is further mounted on a mounting plate, like mounting plate  103  of FIG. 12, which is attached to a mounting ring or equivalent, like ring  13  of FIG.  1 . Stripper  307  removes defective tubes from machine  291  based on command signals from PLC device  297 . 
     Reject station (S) operates as follows: a stripper plate  309  slides back and forth in contact with mandrel  295  unloading any tube on mandrel  295 . Once the thermoplastic tube has been removed, stripper  307  and stripper plate  309  return to their original position. 
     The preferred method for rejecting defective tubes using reject station (S) is as follows: recording selected information on tubes on the closed manufacturing path; generating a signal or multiple signals based on the selected information; inputting the signals into a PLC device and with the use of the signals, rejecting undesirable tubes at a reject station. Selected information may be recorded at an inspection station with the use of a vision camera or electronic eye. The PLC generates a command signal to control rejection station (S) to remove undesirable or defective tubes from the indexing device. 
     Confirmation station (T), illustrated in FIG. 30, is for the purpose of confirming that a tube has been removed by either unload station (R) or rejection station (S) from mandrel  295 . The confirmation station (T) in FIG. 30 is shown as having a sensor arm  319  receiving input and sending output signals to a PLC device (not shown) through control and power line  321 . Sensor arm  319  is mounted on a bracket  323  which may be adjustable (not shown). Confirmation station (T) can alternatively be an electronic or vision means for performing tube confirmation. 
     V. Manufacturing Example 
     A 10 mandrel machine having 7 manufacturing stations, in order: load, heat, mold, treat, print, cure, and unload, was used to manufacture headed and decorated thermoplastic tubes from longitudinally stretched and extruded thermoplastic sleeves. Headed tubes of high quality were produced at a rate of 13 tubes per minute (tubes/min). The following process parameters were used to achieve this output: 
     The machine used a 10 mandrel aluminum indexing table approximately 16 inches in diameter set at a counterclockwise rotation speed of 1.3 revolutions/min. The load station was a pneumatic push-pull device which loaded thermoplastic sleeves from a chain conveyor onto holding mandrels on the indexing table at a rate of 13 sleeves/min. Each sleeve was loaded onto a mandrel so that approximately 0.5 inch of sleeve extended beyond the end of the mandrel. The sleeve was then transported downstream to the second station in the manufacturing path, the heat station. 
     The heat station had a hot air heating probe mounted behind a cooling bushing on a slidable pneumatic carriage. The portion of the sleeve extending beyond the end of the mandrel was heated by air flowing at a rate of 40 cubic cm/second (cc/s) at a temperature of about 720° F., for approximately 3 seconds. The carriage was set at a speed of approximately 0.5 cycle/s. 
     Following the retraction of the carriage, the heated thermoplastic sleeve was indexed one position downstream to the mold station. The mold station was mounted adjacent the heat station on the same slidable pneumatic carriage. The carriage advanced to contact a mold die with the molten preform mass at the end of the heated sleeve. The contact time was about 3 seconds and the mold die temperature was room temperature. 
     The thermoplastic sleeve, now a thermoplastic tube, was next transported to a corona treatment unit. The treatment of the thermoplastic tube occurred for approximately 2 seconds. Following surface treatment, the tube was indexed further downstream to a coat station where a coating was applied to the tube surface. A thin coating was applied around the tube by the application rollers of the station. Following this, the thermoplastic tube was cured by hot air at the cure station, at a temperature of 300° F. from an industrial blower. 
     After hot air curing the finished thermoplastic tube was unloaded from the machine. The total processing time for one tube was 4.6 seconds and the machine produced tubes at a rate of 13 tubes/min. The tubes produced were finished commercially viable tubes of high quality and were later capped to produce headed thermoplastic tubes which were decorated and capped. 
     Producing tubes which have an adhesive label on the aforementioned machine was less complicated. Instead of treating and coating on the machine, a label station was added to apply labels to the thermoplastic tube. All of the parameters and stations previously mentioned were the same except for the addition of the label station. Labeled commercially viable tubes were produced at a rate of 13 tubes/min. 
     VI. Further Embodiments 
     The machine of the present invention is flexible and may be adapted to manufacture thermoplastic tubes of various lengths, thicknesses, weights, diameters, shapes, and complexity. In order adapt a machine to manufacture tubes of a specific diameter, the indexing table is fitted with appropriately sized mandrels and the manufacturing stations are adapted to work on the specific diameter thermoplastic sleeves. Adaptations for the stations may include adjusting the position of the station relative to the mandrel, changing the size of a bushing orifice, or changing the size of a component of a particular station. Additionally the machine of the present invention may altered to accommodate different transportation means - different indexing devices, like an indexing drum. 
     The machine of the present invention is flexible to accept a variety of manufacturing processes on the same machine. 
     Different manufacturing processes are created by the number, sequence and variety of manufacturing stations around the closed manufacturing path. The stations around the path may be changed in a number of ways including: adding or removing manufacturing stations, turning on or turning off stations and rearranging the order of the stations. 
     The following figures will illustrate some of the possible configurations of a machine of the present invention which result in a variety of manufacturing methods. 
     FIG. 32 illustrates a machine  325 , shown without a frame, having an indexing table  327  which rotates counterclockwise in response to indexer  329 ; 6 manufacturing stations: load (A), preheat (B), heat (C), mold (D), label (E) and unload (F); 6 mandrels  331 ; and a manufacturing path capable of 6 process steps, namely: loading, preheating, heating, molding, labeling and unloading. FIG. 33 is a front view of the closed manufacturing path. 
     Even in the embodiment of FIG. 32, the manufacturing path may be rearranged so that labelling is performed prior to heating and molding. To do this the label (E) station would be moved to a mandrel upstream of the preheat (B) station. The advantage of a machine with six manufacturing stations and six mandrels is that it is compact, easy to operate, simple in design and consumes small amounts of power, air, electricity and other inputs. 
     FIG. 34 illustrates a machine  333 , shown without a frame, having an indexing table  335  which rotates counterclockwise in response to indexer  337 ; 6 manufacturing stations: load (A), preheat (B), heat (C), mold (D), label (E) and unload (F); 10 mandrels  339 ; and a manufacturing path capable of 6 process steps, namely: loading, preheating, heating, molding, labeling and unloading. FIG. 35 is a front view of the closed manufacturing path. Machine  333  has 4 expansion mandrels for the addition of manufacturing stations in the future. Machine  333  has the potential to accept more manufacturing process methods than machine  325  of FIG. 32 because of the expansion mandrels. 
     FIG. 36 illustrates a machine  341 , shown without a frame, having an indexing table  343  which rotates counterclockwise in response to indexer  345 ; 10 manufacturing stations: load (A), preheat (B), heat (C), mold (D), label (E), inspect (F), inspect (G), unload (H), reject (I) and confirm (J); 14 mandrels  347 ; and a manufacturing path capable of 10 process steps, namely: loading, preheating, heating, molding, labeling, first inspecting, second inspecting, unloading, rejecting and confirming. FIG. 37 is a front view of the closed manufacturing path. Four expansion mandrels allow for the addition of other manufacturing stations as well as the flexibility to rearrange the manufacturing path illustrated in FIG.  36 . 
     FIG. 38 illustrates a machine  349 , shown without a frame and shown with only partial views of the manufacturing stations, having an indexing table  351  which rotates counterclockwise in response to indexer  353 ; 6 manufacturing stations: load (A), preheat (B), heat (C), mold (D), label (E) and unload (F); 20 mandrels  355 ; and a manufacturing path capable of 6 process steps, namely: loading, preheating, heating, molding, labeling and unloading. If space is not a constraint, machines with larger indexing tables may be built for the future potential of manufacturing expansion. 
     The machine  357  illustrated in FIG. 39 is similar to that of FIG. 38, having five additional manufacturing stations: inspect (F), inspect (G), unload (H), reject (I) and confirm (J) stations. 
     FIG. 40 illustrates a machine  359 , shown without a frame, having an indexing table  361  which rotates counterclockwise in response to indexer  363 ; 9 manufacturing stations: load (A), preheat (B), heat (C), mold (D), label (E), tab seal (F), cap (G), torque (H) and unload (I); 9 mandrels  365 ; and a manufacturing path capable of 9 process steps, namely: loading, preheating, heating, molding, labeling, tab sealing, capping, torquing, and unloading. FIG. 41 is a front view of the closed manufacturing path. This manufacturing machine is compact in size and has the ability to manufacture headed, labelled, tab sealed, capped and torqued thermoplastic tubes. 
     FIG. 42 shows a machine  371  of the present invention having an indexing table  367  upon which is mounted a plurality of oval forming mandrels  369 , for holding oval thermoplastic sleeves to form oval thermoplastic tubes. Oval thermoplastic tubes are formed in a manufacturing path, schematically represented, having  9  manufacturing stations and corresponding process steps: load (A), preheat (B), heat (C), mold (D), treat (E), print (F), cure (G), cap (H) and unload (I). FIG. 43 is a front view of indexing table  367  with oval mandrels  369 . 
     FIG. 44 illustrates a tooling change for a machine  373  of the present invention capable of manufacturing twice as many thermoplastic tubes. Pairs of mandrels  375  are positioned side by side with only a small gap between them on indexing table  377  which rotates in response to indexer  379  so that the manufacturing stations can work on two thermoplastic articles simultaneously. The manufacturing stations may need to be altered slightly to accommodate two articles. FIG. 45 is a front view of machine  373 . 
     Alternatively instead of an indexing table, an indexing drum  381  (FIG. 46) may be used as the indexing device in a machine  383  of the present invention, shown without complete frame (FIG.  47 ). Indexing drum  381  is a drum with the cross-sectional shape of a cylinder or polygon having a plurality of means for supporting thermoplastic sleeves, i.e) mandrels  385  around the outside length of the drum. Manufacturing stations for working on thermoplastic sleeves loaded on mandrels  385  are oriented accordingly so they can perform manufacturing steps on the thermoplastic sleeves (FIG.  47 ). 
     Machine  383  rotates clockwise in response to an indexer (not shown) around the following  8  manufacturing stations and corresponding manufacturing steps: load (A), heat (B), mold (C), treat (D), print (E), cure (F), cap (G) and unload (H), similar to like stations previously described for machine  85  of the second embodiment of a machine of the present invention. The manufacturing stations (A)-(H) are mounted on a mounting ring  387  which is further mounted on a frame of the machine  383 . For clarity, FIG. 47 shows only manufacturing stations (A)-(H) and mounting ring  387  for the first set of mandrels  385  on indexing drum  381 . In production, mounting ring  387  would extend the length of indexing drum  381  and all stations (A)-(H) would be repeated for the corresponding mandrels  385 . Sleeves would be supplied to all load stations by a chute or transportation means (not shown). 
     One advantage of a indexing drum is that more thermoplastic tubes may be produced in a compact space by simply extending the indexing drum and adding more mandrels for supporting thermoplastic sleeves and additional manufacturing stations mounted on a mounting ring. The description of the process method and process control of a machine of the present invention herein applies to a machine having an indexing drum. 
     While there has been illustrated and described several embodiments of the present invention, it will be apparent that various changes and modifications thereof will occur to those skilled in the art. It is intended in the appended claims to cover all such changes and modifications that fall within the true spirit and scope of the present invention.