Abstract:
An apparatus for straightening associated heavy wall tube provided in a coiled configuration at a worksite. The apparatus includes a frame that rotatably receives associated heavy wall tube in a coiled configuration. A straightener device has multiple rollers arranged so that tangents of the rollers receive the associated tube in a linear fashion between the rollers, none of the rollers being powered to rotate. A tube puller engages the tube adjacent a first end thereof, the tube puller moving relative to the frame for advancing the tube from the coiled configuration through the rollers of the straightener device. A truing device rounds the tube after the tube has left the straightener device, the truing device including multiple rollers and none of the rollers are powered.

Description:
BACKGROUND 
       [0001]    This application claims the priority benefit of U.S. provisional patent application Ser. Nos. 61/954,041, filed Mar. 17, 2014 and 62/060,190, filed Oct. 6, 2014, the disclosures of which are expressly incorporated herein by reference. 
         [0002]    This disclosure relates to coiled tubing applications, and more particularly relates to an apparatus and method of straightening coiled tubing for end uses such as when constructing compressed natural gas (CNG) fueling stations, although one or more aspects of the present disclosure may find application in related environments and applications. 
         [0003]    It is common when constructing a CNG fueling station, for example, to use metal tube or tubing. In order to maximize flow of compressed gas from compressors and/or storage cylinders out to dispensers for vehicle fueling, there is a desire to use tubing with ever-larger inner diameters. At the same time, metal tubing wall thickness must be sufficient to handle working pressures of the station, approximately 5500 psi. With ever-larger inner diameters, tubing outer diameters increase proportionally. The requirement to contain 5500 psi results in use of wall thicknesses considered “heavy wall” by industry. When using metal tubing that generally meet requirements of this type, it is common to use linear or straight lengths of tubing (e.g., twenty foot lengths) in which the ends of the tubing are then joined via welding operations with the next adjacent length of tubing. As will be appreciated, joining tube lengths in such a fashion requires a number of joints to be made up. Each joint must be prepared, welded, and inspected to be sure that it satisfies minimum quality control standards. This is a time-consuming and expensive process. 
         [0004]    Using a continuous length of heavy walled tubing supplied from a coiled configuration or a spool would be ideal if the tubing could be effectively installed since such an arrangement would eliminate welding operations, inspections, etc. However, such a system or method has not heretofore been used at least in part because of the inability to uncoil or straighten on a job site the larger inner diameter, heavy wall tubing necessary for sufficient flow. 
         [0005]    Thus a need exists for an improved apparatus and method of installing coiled tubing for such uses. 
     
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
         [0006]      FIG. 1  is a schematic representation of an apparatus and method of supplying coiled tube at a job site. 
           [0007]      FIG. 2  is a perspective view of another embodiment of an apparatus and associated method of straightening coiled tube at a job site. 
           [0008]      FIG. 3  is a top plan view of  FIG. 2 . 
           [0009]      FIG. 4  is a bottom plan view of  FIG. 2 . 
           [0010]      FIG. 5  is a front, elevational view of the apparatus of  FIG. 2 . 
           [0011]      FIG. 6  is a rear, elevational view of the apparatus of  FIG. 2 . 
           [0012]      FIG. 7  is a side, elevational view of the apparatus taken generally from the right-hand side of  FIG. 5 . 
           [0013]      FIG. 8  is a side, elevational view of the apparatus taken generally from the left-hand side of  FIG. 5 . 
       
    
    
     DETAILED DESCRIPTION 
       [0014]    Turning first to  FIG. 1 , a spool  100  of coiled tube  102  is delivered to a job site. It is understood that the coiled tubing is capable of handling a predetermined pressure and flow, for instance greater than  5500  psi. In the CNG fueling station environment, it is common for the tubing  102  to be stainless steel tubing. For example, it is common to use seamless 316 stainless steel annealed tubing having an outer diameter of ½″, ¾″ or 1″ and average wall thickness ranging from 0.065 to 0.139 inches. This tubing is useful for both above-grade and below-grade applications. 
         [0015]    Thus, spools  100  of coiled tube  102  may be easily delivered to a job site. The spool  100  of heavy walled stainless steel tubing  102  is preferably mounted on a support frame  110  so that a free end  112  of the tubing is aligned for connection with a tube puller. The support frame  110  may be configured for mobility (e.g., configured for lifting/transporting with a forklift, a lift assembly, lifted with straps, include wheels on at least one end to facilitate rolling, incorporate a lift jack at one end, etc.) More specifically, a common construction site vehicle  120  such as a skid steerer, loader/back-hoe, etc., is used as the motive power for pulling the free end  112  of the tube  102 . More specifically, a tube pull adapter  122  is connected to the free end  112  of the tube  102 . The adapter  122  may be a wedge-style gripper arrangement with the tube end  112  and in one preferred arrangement includes an opening  124 , such as a clevis or eyebolt-type opening, that receives a first end  126  of a flexible lift strap  128 . A second end  130  of the strap  128  is secured to the construction site vehicle  120 . Of course connections other than the adapter and lift strap can be used to connect the free end  112  of the tube  102  to the tube puller  120 . 
         [0016]    Between the spool  100  and the adapter  122 , the tubing  102  is fed through a straightener device  140 , a counter  144 , and tube support  146  such as a split guide bushing or similar support. Each of these components is preferably securely mounted to the support frame  110 . The frame  110  may include wheels to assist in moving the frame around the job site, and likewise a leveling device or support jack at one end of the frame can be included to hold the support frame  110  in a desired job site location. As illustrated, the straightener device  140  includes multiple rolls or rollers  150  having recessed perimeter surfaces that are contoured to extend over a perimeter portion of the tubing and where the tangents of the rollers are positioned to receive the tubing  102  in a generally linear fashion therebetween. The relative position of the rollers  150  may be adjusted via adjustment mechanism  152  of the straightener device  140 . 
         [0017]    Once the tubing  102  has exited the straightener device  140 , and once a predetermined length of tubing  102  has been straightened by the straightener device  140  and pulled from the spool  100  by the construction site vehicle  120  (as measured, for example, by the counter  144 ), the tubing is cut with a conventional tool (not shown). As will be appreciated, the newly cut end of the tubing can then be arranged for connection to the adapter  122  so that a new length of tubing  102  can be unwound from the spool  100 , fed through the straightener device  140 , and the tubing end connected to the tube puller or construction site vehicle  120  as described above. 
         [0018]    The tube support  146  is preferably located at one end of the support frame  110 . The tube support  146  provides a minimum friction surface, and cooperates with the counter  144  such as a roll footage counter received on the opposite side of the tubing  102  from the tube support. In this manner, an accurate measurement of the length of tubing  102  pulled by the construction site vehicle  120  from the spool  100 , and through the straightener device  140  can be made. Roundness and surface finish of the tubing are important to ensure non-leak performance of the tube fitting connection. The present disclosure allows the tube to be easily straightened without deformation, elongation, or scarring of the outer diameter of the tube. The straightened tube may be used for a wide variety of end uses. For example, one intended use is to insert or feed extended lengths of tubing  102  into a protective sleeve or tube such as HDPE high density polyethylene conduit as is conventionally used in a CNG fueling station. However, the particular end use of the tube straightener assembly should not be deemed limiting to the present disclosure. 
         [0019]      FIGS. 2-8  illustrate a second embodiment, and particularly an embodiment  200  used with heavy wall tube or tubing  202 . In this arrangement  200 , the tube  202  may be a seamless  316  stainless steel annealed structure having an outer diameter of approximately one inch (1″) (+0.005/−0.000) and a minimum wall thickness of 0.120 inches. As will be appreciated, it is known in the industry to use stainless steel tubing for a variety of end uses. When a tube reaches an outer diameter of one inch or greater, special arrangements must be made with a steel mill in order to obtain coiled tubing. That is, tubing of this diameter is typically formed in linear sections, e.g., twenty foot lengths, and opposite ends of the tube are then connected, i.e., welded, to an end of an adjacent tube. As noted in the Background, the straight lengths of tubing require that a number of joints be made, e.g., welded. Each joint must be prepared, welded, and inspected to be sure that the welded joint satisfies minimum quality control standards. As a result, installation may take many days or weeks in order to prepare the welds, weld the ends together, and await inspection. On the other hand, if continuous seamless tubing could be effectively used, a substantial amount of installation time, inspection time and associated cost can be eliminated. 
         [0020]    Although the steel mill can form a continuous heavy wall tube (e.g., 1″ or greater) of extended length (e.g., 170 feet (170′)), transport of such an extended linear length is unfeasible. Therefore, the steel mill loosely coils the tubing  202 . In other words, one inch or greater diameter tube  202  is typically not placed on a spool (as in the embodiment of  FIG. 1 ), but rather is bent at the mill into a loosely coiled shape  204 . The coil shape  204  allows the heavy wall tubing  202  of one inch or greater to be shipped to a job site. As will be further described below, there may be instances where special designed spools are created where 1 inch or greater coiled tube is level-wound on the custom spool. Consequently, straightener device  200  receives either loosely coiled tubing  202  or level-wound tubing received on a special built spool  206  (and the embodiment of  FIGS. 2-8  illustrate both the loosely coiled tube and the spool with level-wound tubing to represent that either supply of coiled or would tubing can be accommodated by the tube straightener assembly). 
         [0021]    At the job site, it becomes necessary to straighten the tubing  202  for the final end use. More particularly, the coil shape  204  is loaded onto a support or carousel  210  that has a diameter slightly greater than the coil shape in order to support the tubing  202  on the carousel. The carousel  210  has a substantially planar upper surface that is mounted on a rigid support frame  212 . The frame may be easily transported to and from a job site, and once located, can be staked or otherwise secured against movement during use. As shown throughout these figures, the carousel  210  is adapted to receive either the loosely wound coil of tubing  202  or is adapted to receive the spool  206  with the level wound tubing previously wound thereon at the tubing manufacturer/supplier. The loosely wound coil  204  of tubing  202  would be secured to the carousel  210 , for example, through use of support members or posts  220  and clamps or securing members  222  that secure and support the loosely wound coil on the upper surface of the carousel  210 . Two or more support members or posts  220  extend outwardly, i.e., upwardly, from the surface  212  at locations spaced radially outward from a central axis or axis of rotation  216 . Shown here are four posts  220  substantially equi-spaced about the carousel  210  and at substantially the same radius from the rotational axis of the carousel, although a greater or lesser number of posts may be used. The posts  220  are preferably mounted for limited radial movement or adjustment within respective slots  224  ( FIG. 2 ) that extend in a substantially radial direction. In this manner, the coil shape  204  of extended length, heavy wall tubing  202  is placed/loaded onto the upper surface of the carousel  210  at the job site with the posts  220  typically initially positioned at radial innermost positions while the coil shape  204  is loaded on the carousel  210 . The posts  220  are located within a central opening of the coil shape  204 . At least one of the securing members  222  clamps a portion of the tubing  202  adjacent a first end and preferably each of the securing members will be used to clamp down peripheral portions of the first end of the tubing at circumferentially spaced locations on the surface of the carousel  210 . The posts  220  are radially adjustable relative to the surface of the carousel  210  so that once the loosely wound coil  204  is received thereon, the posts are moved radially outward in their respective slots  224  into abutting engagement with the inner periphery or inner diameter of the loosely wound coil. Once the posts  220  are positioned at the desired location, the posts are tightened down relative to the surface of the carousel and serve to support the loosely wound coil of tubing  202  on the carousel  210 . 
         [0022]    Alternatively, the carousel  210  is removed and the carousel table  250  is mounted to center hub  240 , particularly around a support collar  242  that cooperates with the center hub to allow rotation of the carousel table  250  and spool  206  relative to the frame  212 . The carousel table  250  ( FIGS. 5-8 ) interconnects with the spool  206  via spool lock  251  ( FIG. 7 ) to allow the two components to rotate together. 
         [0023]    Next, a second end  270  of the tubing  202  is engaged with a tube pull adapter (not shown but similar to the adapter  122  of  FIG. 1 ). For example, one preferred tube pull adapter is a wedge-style gripper arrangement that grasps the tube second end  270 , and the adapter is in turn connected to a tube puller (not shown, but understood that a common construction site vehicle  240  such as a skid steerer, loader/backhoe, etc., is one type of tube puller that can be used as the motive power for pulling the free end  270  of the tube  202 ). It will also be appreciated that the arrangement could be modified or supplemented with a powered feed system such as a track drive, pinch rollers, or similar mechanism that either pushes or pulls the tubing  202  through/into a straightener device  280 , although the straightener device is a non-powered set of rollers. As the second end  270  is pulled from the carousel  210  along a substantially tangential path, the tubing  202  is fed into the straightener device  280 . The straightener device  280  is similar to that shown and described in connection with the embodiment of  FIG. 1 . For example, multiple rollers  282  are arranged to receive the tubing  202  in a generally linear fashion therebetween. The rollers  282  of the straightener device  280  may be adjusted via adjustment mechanism  284 . The straightener device  280  receives the tubing therethrough, and particularly the second, free end  270  of the tubing  202  is fed tangentially from the coil  204  or spool  206 . The series of rollers  282 , for example five individual rollers, are part of the straightener device  280 . The rollers  282  are non-powered, i.e. the tubing end  270  is fed linearly through the array of peripheral edges of the rollers where three rollers are received on one side of the tubing and a pair of rollers received on the other side of the tubing. The adjustment mechanism  284  allows the substantially linear passage between the rollers  282  to be adjusted if so desired. 
         [0024]    Upon exiting the straightener device  280 , the tubing  202  has been straightened. Thus, the tubing  202  may be straightened by pulling the tube second end  270  from the carousel  210  and through the straightener  280 . As will be appreciated, as the pulling operation nears completion, and the first end of the tubing remains clamped to the carousel  210 , it will be necessary to unclamp the tube first end from the carousel for passage through the straightener device  280 . 
         [0025]    Downstream of the straightener device  280  is provided a calibrating or truing device  290 . The calibrating device  290  includes cooperating pairs of rollers  292   a,    292   b ,  292   c  through which the tubing end  270  passes. Each pair of rollers includes a separate adjusting mechanism  294   a,    294   b,    294   c  that allows selective, separate alteration of the gap between the roller pair. After the previously coiled tubing has been straightened in the straightener device  280 , the tubing may be out of round. If the tubing is substantially out of round, standard compression type fittings (not shown), for example, may not properly seal on the outer diameter tube. By providing the pairs of rollers  292   a ,  292   b,    292   c  through which the tubing end  270  passes, the outer diameter of the tube is substantially encompassed and deformation that may occur in the outer diameter of the tube during the straightening process can be corrected by “truing” the outer diameter of the tube. Again, non-powered rollers  292  are preferred particularly since jobsites or worksites are often without power sources. 
         [0026]    A primary benefit of the present disclosure relates to portability of the system. Another advantage resides in the fact that the tube can be fed without the use of a complex track feed, or a hydraulic pinch roller feed system requiring electricity and hydraulics. The complex track feed and hydraulic pinch roller feed system are customary feed mechanisms for wire and tube straightening in the industry that can be used if the worksite will accommodate powering such a system, but in other instances such track feed/pinch roller systems are not readily adaptable to on-site heavy walled tube straightening. As a consequence, it is important that the device be capable of straightening the heavy wall tubing without powered rollers. 
         [0027]    As is evident, the continuous length of tubing can be effectively straightened. All of this can be achieved without electrical or hydraulic tooling required on-site, and a number of end-to-end welds are eliminated by use of an elongated, loosely coiled tubing or level-wound tubing on a spool that is subsequently straightened on-site. Moreover, one skilled in the art will recognize that the apparatus and method described herein with regard to one embodiment may also find application with smaller diameter tubes (e.g., as described in connection with  FIG. 1 ) or with still other smaller or greater diameter tubing. 
         [0028]    This written description uses examples to describe the disclosure, including the best mode, and also to enable any person skilled in the art to make and use the disclosure. The patentable scope of the disclosure is defined by the claims, and may include other examples that occur to those skilled in the art. Such other examples are intended to be within the scope of the claims if they have structural elements that do not differ from the literal language of the claims, or if they include equivalent structural elements with insubstantial differences from the literal language of the claims. Moreover, this disclosure is intended to seek protection for a combination of components and/or steps and a combination of claims as originally presented for examination, as well as seek potential protection for other combinations of components and/or steps and combinations of claims during prosecution. For example, variations of this system can be used with any type of power feed for pushing or pulling the tube. Further, power assist if available at the work site may also be advantageously employed to close and open the roller mechanism. It is also contemplated that another set of rollers may be mounted in a plane perpendicular to the first set of rollers. The system is ideally collapsible and may also be permanently mounted to a trailer, truck, or the like for ease of transportation.