Abstract:
A pipe installation device and a method for laying consecutive lengths of bell and spigot pipe. The pipe installation device installs sequential pipe lengths. The pipe installation device includes a pipe supply system and a pipe alignment system attached to a carriage. The pipe alignment system is positioned to receive a pipe length from the pipe supply system and align the pipe length with a pipe length previously positioned in the pipe alignment system. The pipe installation device also includes a pipe joining system for joining the two pipe lengths positioned in the pipe alignment system. A pipe restraint system applies a restraining force against one pipe length while the pipe joining system joins the two pipe lengths.

Description:
[0001]     The present application is a Continuation-in-Part Application of a non-provisional application Ser. No. 11/004,554 entitled  Device and Method for Laying and Joining Pipe  filed Dec. 3, 2004, which claims the benefit of the filing date of a Provisional Patent Application Ser. No. 60/528,318, filed on Dec. 8, 2003, entitled  Automated Pipe Laying Device , which are incorporated by reference herein. 
     
    
     BACKGROUND OF THE INVENTION  
       [0002]     1. Technical Field  
         [0003]     The present invention relates generally to devices for laying pipe and, more specifically, to a device that advances along the course of pipeline construction, lays and joins pipe.  
         [0004]     2. Background of the Invention  
         [0005]     The process of laying sections of pipe along the course of pipeline construction when a bell and spigot pipe is being installed, involves laying sequential pipe lengths and the joining the sequential pipe lengths by applying a mechanical pressure to a most recently laid section of pipe in order to engage the spigot end of that length with the bell end of a previously laid length. When the course of pipeline construction lies underground, construction involves the excavation of a trench to a desired depth followed by placement and positioning of pipe in the trench. This method involves placing one or more workers in the trench to guide a lowered section of pipe into contact with a previously installed section. The workers must also disengage rigging from the pipe that was used in lowering the length into the trench. Once a pipe length is positioned in the trench, it is manually joined to a preceding pipe length. In deep trenches, a work crew commonly works within the confines of a trench shoring box that provides increased safety in the trench working condition.  
         [0006]     Excavation and placement functions are typically performed by a single piece of equipment, an excavator. The excavator is a relatively costly piece of equipment, often track mounted, that performs primarily an excavation function. One disadvantage of the current popular method is the fact that a costly piece of equipment is oftentimes moved between tasks, excavation and pipe installation, that may otherwise proceed at different rates. Additionally, where shoring is required it is often moved along the length of the trench by the excavator as the pipeline advances requiring yet a third function or task of the excavator.  
         [0007]     Devices, including excavators that position or otherwise place pipe at the bottom of a trench, pose a number of disadvantages. These devices are positioned outside the trench and typically place pipe by maneuvering along a top edge of the trench over tailings that have been placed alongside the trench during excavation. These surfaces are rarely, if ever, flat and therefore make the task of placement more difficult. Additionally, activity at grade level, depending on soil conditions, may increase a probability of trench collapse. Additional problems are seen when laying bell and spigot pipe. For instance, manufacturer&#39;s and job specifications typically require that the spigot end of a first pipe length be inserted into a bell end of a sequential pipe length a specified distance and that the spigot end not be “bottomed” out in the bell end when inserted. Additionally, manufacturer&#39;s and job specifications typically require that when the pipe is laid on a substrate that a “divot” be provided for the bell end to lay in so that undue stress is not created in the pipe at the transition of the bell to the barrel of the pipe due to the differing diameters of the bell and the barrel portions of the pipe.  
         [0008]     Advantage may therefore be found in providing a device that is capable of laying and joining pipe in a trench. Additional advantage may be found in providing an apparatus that advances along the course of pipeline construction, for instance a pre-excavated trench, laying and joining pipe in the trench. Advantage may also be found in providing a device that aligns sequential lengths of bell and spigot pipe and seats a spigot end of a first pipe length into the bell end of a sequential pipe length. Additional advantage may be found in providing an apparatus that provides a divot for the bell to lie in as the device proceeds along the course of pipeline construction.  
       SUMMARY OF THE INVENTION  
       [0009]     These and other objectives are met by the pipe installation device of the present invention. As such, the present invention is directed to a pipe installation device for installing sequential pipe lengths along the course of pipeline construction, the device including a carriage carriage movable along the course of pipeline construction. A pipe supply system and a pipe alignment system are attached to the carriage, the pipe alignment system positioned to receive a pipe length from the pipe supply system and align the pipe length with a pipe length previously positioned in the pipe alignment system. The pipe alignment system includes a pipe restraint system adapted to selectively apply a restraining force against one of the pipe lengths and a pipe joining system adapted to join the pipe lengths in the pipe alignment systems. The pipe installation device also includes a power supply adapted to provide power to the pipe feed and pipe alignment systems and a control system adapted to control the pipe feed, and pipe alignment systems. The preferred embodiment of the invention also includes a drive system adapted for advancing the pipe installation device along the course of pipeline construction and a steering system adapted to steer the carriage along the course of pipeline construction, both connected to the carriage. In addition, the preferred embodiment includes a trench sidewall sensing system connected to the carriage and provides an output to the control system representative of the location of the trenc with regard to the carriage.  
         [0010]     In the preferred embodiment, the pipe supply system includes a pipe storage rack adapted to hold one or more pipe lengths, a pipe release mechanism adapted to selectively release a single pipe length from the pipe storage rack and a pipe feed system adapted to lower the pipe length released from the pipe rack onto the pipe alignment system.  
         [0011]     Alternately, the present invention is directed to a pipe alignment system adapted to receive a first pipe length from a pipe feed mechanism in a forward section of the pipe alignment system, hold the first pipe length in a linearly aligned relationship to a second pipe length positioned on a rearward section of the pipe alignment system and join a spigot end of the first pipe length to a bell end of the second pipe length by inserting the spigot end of the first pipe length into the bell end of the second pipe length a specified distance.  
         [0012]     In the preferred embodiment, the pipe joining system of the pipe installation device includes a pipe seating ram adapted to exert a force against a forward end of the pipe length positioned in the pipe alignment system forward section, the force substantially parallel to a longitudinal axis of the pipe length positioned in the pipe alignment system forward section. The force exerted by the pipe seating ram is adjustable or variable so that various pipe diameters may be accommodated and so that sufficient force is applied to insert a spigot end of the forward pipe length into the bell end of the rearward or trailing pipe length. Ideally, the force applied should be sufficient to overcome the resistance of a gasket positioned in a gasket race of the bell to insertion of the spigot end, but not so great so as to “bottom out” the spigot in the bell. A pipe restraint system selectively operates either to allow rearward movement of the rearward pipe length relative to the forward advancement of the pipe installation device or, to restrain the rearward pipe length against rearward movement relative to the forward advancement of the pipe installation device.  
         [0013]     The present invention is also directed to a method for laying consecutive lengths pipe using an pipe installation device including the steps of advancing the pipe installation device along the course of pipeline construction, feeding a pipe length onto a forward section of a pipe alignment system, aligning the pipe length with a pipe length positioned on a rearward section of the pipe alignment system, restraining the pipe length positioned on a rearward section of the pipe alignment system against rearward movement, joining the pipe length in the forward section of the pipe alignment system by exerting a force against the pipe length positioned on the forward section of a pipe alignment system substantially along a longitudinal axis of the pipe length and consequently against the previously laid pipe length positioned in the rearward section of the pipe alignment system so that a spigot end of one of the pipe length in the forward section of a pipe alignment system engages a bell end of the pipe length positioned in the rearward section of the pipe alignment system.  
         [0014]     Once the pipe length in the forward section of a pipe alignment system and the pipe length positioned in the rearward section of the pipe alignment system are joined, restraint of the pipe length positioned in the rearward section of the pipe alignment system is discontinued and forward travel of the pipe installation device resumes. The joined pipe lengths including the pipe length positioned in the forward section of a pipe alignment system and the pipe length positioned in the rearward section of the pipe alignment system are deposited at a rear end of the pipe alignment system as the pipe installation device resumes its forward travel.  
         [0015]     The present invention consists of the parts hereinafter more fully described, illustrated in the accompanying drawings and more particularly pointed out in the appended claims, and methods for laying consecutive lengths pipe using an pipe installation device, it being understood that changes may be made in the form, size, proportions and minor details of construction without departing from the spirit or sacrificing any of the advantages of the invention. 
     
    
     BRIEF DESCRIPTION OF THE DRAWINGS  
       [0016]      FIGS. 1, 6 ,  9 ,  11  and  12  are representative side elevations depicting a pipe installation device according to a preferred embodiment of the present invention;  
         [0017]      FIG. 2  is a representative top elevation depicting a carriage of a pipe installation device according to a preferred embodiment of the present invention;  
         [0018]      FIG. 3  is a representative rear elevation depicting a carriage for the pipe installation device according to a preferred embodiment of the present invention;  
         [0019]      FIGS. 4 and 7  are representative top elevations depicting a pipe installation device according to a preferred embodiment of the present invention;  
         [0020]      FIGS. 5, 8  and  10  are representative rear elevations depicting a pipe installation device according to a preferred embodiment of the present invention;  
         [0021]      FIG. 13  is a representative top elevation depicting the carriage and various features of the pipe storage rack and feed systems in exploded format for the pipe installation device according to a preferred embodiment of the present invention;  
         [0022]      FIGS. 14, 16 ,  18  and  20  are a representative rear partial cutaway views depicting operation of a pipe release mechanism for the pipe installation device according to a preferred embodiment of the present invention;  
         [0023]      FIGS. 15, 17 ,  19  and  21  are representative side elevations depicting operation of a pipe release mechanism for the pipe installation device according to a preferred embodiment of the present invention;  
         [0024]      FIG. 22  is a representative top elevation depicting a pipe alignment system according to a preferred embodiment of the present invention;  
         [0025]      FIGS. 23 and 24  are representative side elevations depicting a pipe alignment system, pipe restraint system and bell divot systems for the pipe installation device according to a preferred embodiment of the present invention;  
         [0026]      FIG. 25  is representative bottom elevation depicting a pipe restraint system for the pipe installation device according to a preferred embodiment of the present invention;  
         [0027]      FIGS. 26 and 27  are representative side cross-sectional views depicting a pipe restraint system for the pipe installation device according to a preferred embodiment of the present invention;  
         [0028]      FIGS. 28 and 29  are representative side elevations depicting a divoting mechanism of the pipe installation device according to a preferred embodiment of the present invention;  
         [0029]      FIG. 30  is a representative top elevation depicting a divoting mechanism of the pipe installation device according to a preferred embodiment of the present invention;  
         [0030]      FIG. 31  is a representative top cutaway view depicting various features of the drive and steering systems for the pipe installation device according to a preferred embodiment of the present invention;  
         [0031]      FIG. 32  is a schematic representation depicting the power and control systems for the pipe installation device according to a preferred embodiment of the present invention; and  
         [0032]      FIGS. 33A and 33B  are a schematic flow diagrams depicting operation of the pipe installation device according to a preferred embodiment of the present invention. 
     
    
     DETAILED DESCRIPTION  
       [0033]      FIGS. 1, 6 ,  9 ,  11  and  12  are side elevations showing pipe installation device  10  to advantage. Pipe installation device  10  includes carriage  11  including frame  15  supported by a plurality of wheels, wheels  12 A and  12 C being shown in the referenced figures. Pipe installation device  10  also includes pipe supply system  20  and power and control systems housing  16  shown supported by carriage  11 . Frame  15  includes a pair of swing arms  51  and  52  which extend laterally from frame  15 . Trench sidewall sensing system  50  is shown connected to and supported by swing arms  51  and  52 . Trench sidewall sensing system  50  senses a location of trench T relative to the position of carriage  11 .  FIGS. 1, 6 ,  9 ,  11  and  12  show trench sidewall sensing system  50  including angular motion sensors  55  and  56  positioned at the upper ends of swing arms  51  and  52  respectively. Control arms  57  and  58 , depend from swing arms  51  and  52  and sidewall contact paddles  53  and  54  are connected at the distal ends of control arms  57  and  58  respectively.  FIGS. 1, 6 ,  9 ,  11  and  12  also show sensors  141  which senses when a pipe length positioned in the forward portion of pipe alignment frame  69  has passed the location of sensor  141  and sensor  144  which senses when a pipe length been lowered onto the forward portion of pipe alignment frame  69 .  
         [0034]     Pipe supply system  20  is shown including pipe storage rack  25 , pipe release mechanism  30 , pipe feed system  40 . Pipe storage rack  25  includes uprights  23  and  24  and pipe feed system  40  includes catch arms  26  and  27  all of which aide in containing pipe lengths in pipe supply system  20 . Pipe release mechanism  30  is adapted to selectively release a single pipe length P from pipe storage rack  25  to pipe feed system  40  which is adapted to lower a pipe length P released from pipe rack  25  onto pipe alignment system  60 . Pipe alignment system  60  is shown positioned on floor F of trench T and attached at upright  66  to carriage  11  by tow bar  17  and cable  18 . Shear pin  19  attaches cable  18  to tow bar  17  so that in the event that pipe alignment system  60  becomes bound for any reason and cannot advance with carriage  11 , shear pin  19  will fail without damaging components of either pipe alignment system  60  or carriage  11 . Pipe alignment system  60  is shown supported by wheel  61 A and skid  62 . Pipe joining system  70  and pipe restraint system  80  are shown carried by pipe alignment frame  69  of pipe alignment system  60 . Bell divot system  75  is shown carried by pipe alignment system  60 .  
         [0035]      FIGS. 2, 4  and  7  are top plan elevations of carriage  11  including frame  15  supported by wheels  12 A through  12 D.  FIGS. 4 and 7  show pipe alignment system  60  positioned in trench T. Referring now to  FIGS. 2, 4  and  7 , pipe supply system  20  is shown including pipe storage rack  25 , pipe release mechanism  30 , pipe feed system  40 . Power and control systems housing  16  and trench sidewall sensing system  50  are shown connected to and supported by frame  15 . Frame  15  includes inclined cross-frame members  95 ,  96 ,  97  and  98 . Pipe supply system  20  includes first inclined rail  21  and second inclined rail  22 . Uprights  23  and  24  restrict lateral movement or shifting of pipe off of pipe rack  25 . When pipe is released from pipe rack  25  by pipe release mechanism  30 , as described below, catch arms  26  and  27  restrict lateral movement or loss of pipe from pipe feed system  40 . Pipe feed system  40  is shown including winches  43  and  44 , straps  41  and  42  which may be extended and retracted by winches  43  and  44 . A second end of straps  41  and  42  are attached to arms  45  and  46  respectively. Catch arms  26  and  27  are connected and extend from arms  45  and  46  respectively.  
         [0036]     Trench sidewall sensing system  50  senses a location of trench T relative to the position of carriage  11  and includes angular motion sensors  55  and  56  positioned at the upper ends of arms  51  and  52  respectively. Control arms  57  and  58 , (shown in  FIG. 1 ), depend from swing arms  51  and  52 . Sidewall contact paddles  53  and  54  are connected at the distal ends of control arms  57  and  58  respectively. Sidewall contact paddles  53  and  54  are adapted such that in the event contact is made with either sidewall SW 1  or SW 2  of trench T, sidewall contact paddle  53  or  54  are angularly displaced, (as shown in  FIGS. 2 ), causing rotation of its respective attached control arm  57  or  58 , (as shown in  FIGS. 1 ). The associated angular motion sensor  55  or  56  senses an angular displacement of control arm  57  or  58  providing an output to controller  140 , shown in  FIG. 32 , representative of the degree of angular displacement of the sidewall contact paddle. Control of the steering of carriage  11  as a function of the output of angular motion sensors  55  and  56  is discussed in greater detail below.  
         [0037]      FIGS. 4 and 7  show pipe installation device  10  including pipe alignment system  60  positioned on floor F of trench T and attached to carriage  10 . Referring to  FIGS. 4 and 7 , pipe alignment system  60  is shown supported by wheel  61 A and  61  B. Pipe alignment system  60  includes pipe restraint system  80  and pipe joining system  70 . Pipe joining system  70  and pipe restraint system  80  are shown carried by pipe alignment frame  69 .  
         [0038]      FIG. 3  shows a rear plan elevation of carriage  11  configured for transportation. Carriage  11  includes frame  15  and pipe supply system  20  including pipe rack  25 . As seen in  FIG. 3 , pipe rack  25  includes inclined cross-frame member  97 . Power and control systems housing  16  is shown supported by frame  15 . Wheels  12 A and  12 B are mounted to axle  13  which is pivotably attached to frame  15  which assists with articulation of carriage  11  over irregular terrain often encountered at the edge of trench T. Pipe storage rack  25  and power and control systems housing  16  are shown supported by frame  15 . Swing arm  51  of sidewall sensing system  50  is shown in an “up” position. Angular motion sensor  55 , is shown positioned at an upper end of control arm  57  and sidewall contact paddle  53  is connected at a distal end control arm  57 . With the swing arms in the “up” position, carriage  11  may be transported on most roadways without special permitting.  FIG. 3  also shows upright  23  and catch arm  26  of pipe storage rack  25 . Outer release arm  31  of pipe release mechanism  30  is shown in an upright position.  
         [0039]      FIGS. 5, 8  and  10  are rear elevations depicting pipe installation device  10  including carriage  11  including frame  15  shown supported by a rear wheels  12 A and  12 B, shown in the referenced figures connected to axle  13 . Pipe installation device  10  also includes pipe supply system  20  and power and control systems housing  16  shown supported by carriage  11 .  FIG. 5  shows pipe release mechanism  30  including outer release arm  31 , while  FIGS. 8 and 10  show inner release arm  33 , which alternately restrict or selectively release pipe P from rolling down first inclined rail  21 . Pipe release mechanism  30  is adapted to selectively release a pipe length P from pipe storage rack  25  and pipe feed system  40  for lowering the pipe length P onto pipe alignment system  60 . Pipe alignment system  60  is shown positioned on floor F of trench T and includes frame  69  and skid  62 . Rearward pipe length is shown in  FIG. 8  positioned on pipe alignment frame  69  restrained by pipe restraint system  80  and forward pipe length FP is shown held in pipe lowering system  40 . Pipe feed system  40  is shown including winch  43 , strap  41 , which may be extended and retracted by winch  43 , and arm  45  to which a second end of strap  41  is attached and to which catch arm  26  is connected and from which it extends upwardly. In  FIGS. 5, 8  and  10 , swing arm  51  of sidewall sensing system  50  is shown in a lowered position between sidewalls SW 1  and SW 2  of trench T. Angular motion sensor  55 , is attached at an upper end of control arm  57  and sidewall contact paddle  53  is connected at a distal end control arm  57 .  FIGS. 5, 8  and  10  also show pipe storage rack  25  including first inclined rail  21 , upright  23  and catch arm  26 .  
         [0040]      FIG. 13  is a top elevation showing carriage  11  as well as various features of pipe supply system  20  including pipe storage rack  25 , pipe release mechanism  30  and feed system  40  in an exploded format. As shown, carriage  11  includes frame  15  supported by wheels  12 A through  12 D. Pipe storage rack  25 , pipe release mechanism  30 , pipe feed system  40 , power and control systems housing  16  and trench sidewall sensing system  50  are all connected to and supported by frame  15 . Pipe lengths P are shown supported by first inclined rail  21  and second inclined rail  22 .  
         [0041]     Referring to  FIG. 13 , ramp slide extenders  27  and  28  insert into first inclined rail  21  and second inclined rail  22  respectively and include uprights  23  and  24  and permit the widening of pipe storage rack  25  when in use, while allowing carriage  11  to be reduced in width for transport. Winch support arms  93  and  94  slideably engage inclined cross-frame members  95  and  96  and permit the widening of frame  15  to extend over trench T, (not shown in  FIG. 13 ), in use. Similarly, keeper slide extenders  91  and  92  slideably engage cross-frame members  97  and  98  and permit the widening of frame  15  to extend over trench T, (not shown in  FIG. 13 ), while the device is in use and can be retracted for transport. Winch support arms  93  and  94  include cross-frame member carriers  90  and  99 , through which cross-frame members  91  and  92  are inserted, prior to engaging inclined cross-frame members  97  and  98 . All of the above adjustments that permit widening and narrowing of carriage  11  may be performed manually or in the alternative they may be automated using for instance servo motors or hydraulics.  
         [0042]      FIG. 13  also shows pipe release mechanism  30 , for selectively releasing a pipe length P from pipe storage rack  25  and pipe feed system  40 . Pipe feed system  40  is shown including winches  43  and  44  connected to winch support arms  93  and  94  and arms  45  and  46  to which a second end of straps  41  and  42  respectively are attached and to which catch arms  26  and  27  are connected and extend. FIGS.  13  also shows trench sidewall sensing system  50  including swing arms  51  and  52  each connected to frame  15  in an articulating manner. Angular motion sensors  55  and  56 , are positioned at the distal ends of swing arms  51  and  52  respectively. Tow bar  17  attaches to swing arm  52  and shear pin  19  attaches to tow bar  17 . Control arms  57  and  58  depend from swing arms  51  and  52 . Sidewall contact paddles  53  and  54  are connected at the distal ends of control arms  57  and  58  respectively. Finally,  FIG. 13  shows pipe release mechanism  30  including outer release arms  31  and  32 , inner release arms  33  and  34  connected by release linkage  35 . Release ram  36  is shown operatively connected to release linkage  35 .  
         [0043]      FIGS. 14-21  detail the operation of pipe release system  30  that selectively releases a pipe length P from pipe storage rack  25  to pipe feed system  40 . More particularly, FIGS.  14 , 16 , 18  and  20  are rear elevations of carriage  11  depicting pipe lengths P being held in pipe storage rack  25  or selectively released by operation of pipe release system  30 . Carriage  11  includes frame  15  supported by a plurality of wheels, wheels  12 C and  12 D being shown in the referenced figures attached to axle  14 . Pipe storage rack  25  and power and control systems housing  16  shown supported by carriage  15 . Upright  24  extends in a vertical upright orientation from second inclined rail  22 . Winch support arm  94  is shown extending laterally at an incline from frame  15 .  FIGS. 15, 17 ,  19  and  21  are side elevations showing pipe release mechanism  30 , pipe storage rack  25  and power and control systems housing  16  supported by carriage  15 .  
         [0044]     Pipe release mechanism  30  includes outer release arms  31  and  32 , inner release arms  33  and  34  connected by release linkage  35 . In  FIGS. 15, 17 ,  19  and  21 , release ram  36  is shown operatively connected to release linkage  35 . At  FIGS. 14 and 15 , outer release arms  31  and  32  hold forward pipe lengths P on frame  15 . At  FIGS. 16 and 17 , release ram  36  selectively operates to isolate forward pipe length FP between outer release arms  31  and  32  and inner release arms  33  and  34 . As release ram  36  continues its extension, release linkage  35  operates outer release arms  31  and  32  and inner release arms  33  and  34  to simultaneously release forward pipe length FP retaining pipe length P in pipe storage rack  25 , as shown in  FIGS. 18 and 19 . (See also  FIGS. 7 and 8 ).  FIGS. 20 and 21  show pipe length P being retained in pipe storage rack  25  until the next subsequent cycle of pipe release system  30 .  
         [0045]      FIGS. 6-12  show a sequence of operation of pipe feed system  40 . As rearward pipe length RP passes sensor  141 , pipe feed mechanism  30  is triggered and forward pipe length FP is released from pipe rack  25 . As seen in  FIGS. 6 and 8 , once forward pipe length FP rolls down inclined pipe ramps  21  and  22 , it is caught in straps  41  and  42 . Straps  41  and  42  are connected at a first end to winches  43  and  44  respectively and at their respective second ends to arms  45  and  46 . Sensor  142 , a limit switch shown in  FIG. 32 , senses when winches  43  and  44  have retracted straps  41  and  42 . Sensor  142  provides an output to controller  140 , shown in  FIG. 32 , which triggers operation of release ram  36  to release forward pipe length FP from pipe supply  20  as discussed more fully herein below. Sensor  143 , a limit switch shown in  FIG. 32 , is tripped when forward pipe length FP is released from pipe supply rack  20  into pipe feed system  40 . When sensor  143 , senses the release of forward pipe length FP, controller  140 , shown in  FIG. 32 , initiates operation of winches  43  and  44  to begin lowering forward pipe length FP onto pipe alignment frame  69  as shown in  FIGS. 9-12 . At this time, controller  140 , shown in  FIG. 32 , also initiates extension of release ram  36 , shown in  FIG. 21 , to prepare for the release of the next pipe length P in the following pipe release cycle. Sensor  144 , seen in FIGS.  6 ,  9 , 11  and  12 , senses when forward pipe length FP has been lowered onto pipe alignment frame  69  and provides an output to the controller  140 , shown in  FIG. 32 , which then continues operation of winches  43  and  44  for a preset time period to allow straps  41  and  42  to lower to a point where they are clear of forward pipe length FP as seen in  FIGS. 9-12 .  
         [0046]      FIGS. 22-24  provide a more detailed depiction of pipe alignment system  60 . Pipe alignment frame  69  is shown supported by skid  62  and wheels  61 A and  61  B, shown in  FIG. 22 . Pipe alignment frame  69  includes pipe alignment frame  69  including alignment frame forward section  63  and alignment frame tail section  64 . Upright  66  is connected to and extends vertically from pipe alignment frame  69  and cable  18 , shown in  FIGS. 1 and 24 , is connected to lug  67 . A plurality of V-rollers  65 A- 65 F are positioned along the length of pipe alignment frame  69 . Once forward pipe is positioned on pipe alignment frame  69  as seen in  FIG. 23 , forward pipe length FP and rearward pipe length RP are aligned along longitudinal axis L by the fact of their placement on V-rollers  65 A- 65 F. It should be noted that V-rollers  65 A- 65 F are adjustable to accept pipe having a variety of diameters. Alignment frame forward section  63  includes a pair of substantially parallel and spaced apart frame elements  63 A and  63 B. Similarly, alignment frame tail section  64  includes a pair of substantially parallel and spaced apart frame elements  64 A and  64 B. Alignment frame forward section  63  and alignment frame tail section  64  are joined as shown in  FIGS. 22 and 23  and consequently may be separated for transport. Pipe alignment frame  69  is supported by wheels  61 A and  61 B, (shown in  FIG. 21 ), and skid  62 . Upright  66  with lug  67  provide a point of attachment to connect pipe alignment system  60  to carriage  11 , as shown in  FIG. 1 .  FIG. 24  shows forward pipe length FP positioned on pipe alignment frame  69  and rearward pipe length RP is positioned in pipe alignment frame  69  extending along alignment frame forward section  63  onto alignment frame tail section  64 .  
         [0047]     As shown  FIGS. 22-24 , pipe joining system  70  is attached to pipe alignment frame  69  of pipe alignment system  60 . Pipe joining system  70  includes joining ram  71 , which is connected at a first end between frame elements  63 A and  63 B of alignment frame forward section  63 . A second end of joining ram  71  is connected to push plate  72 , which travels with the extension and retraction of joining ram  71 .  
         [0048]      FIGS. 22-24  also show pipe restraint system  80  attached to pipe alignment frame  69 . As shown in  FIG. 22 , pipe restraint system  80  includes retainer ram  81  and retainer forks  82  and  83 .  FIGS. 23 and 24  show retainer ram  81  and retainer fork arm  83  connected to pipe alignment frame  69 .  
         [0049]      FIGS. 22-24  also show bell divot system  75  connected to pipe alignment frame  69 . As seen in  FIGS. 22-24 , bell divot system  75  includes divot ram  78  and divot cutter  79 . As shown in  FIG. 23 , pipe alignment system  60  is adapted to align forward pipe length FP along a longitudinal axis L with rearward pipe length RP positioned on pipe alignment frame  69 .  
         [0050]     Referring to  FIGS. 25-27 , pipe restraint system  80  is shown including retainer ram  81  connected to retainer forks  82  and  83  by link arm  84 . In  FIGS. 26 and 27 , pipe restraint system  80  is shown connected to alignment frame forward section  63  between V-rollers  65 C and  65 D. Retainer fork forks  82  and  83 , seen in  FIG. 25 , and retainer fork  83 , seen in  FIGS. 26 and 27 , are mounted on shaft  85  and are fixably slideable along shaft  85  to accommodate various pipe diameters having different bell sizes. Slide linkage  86  permits adjustment of a location of shaft  85  with respect to pipe alignment frame  69  also to accommodate various pipe diameters having different bell sizes. Retainer forks  82  and  83  pivot on shaft  85  between a “down” position as shown in  FIGS. 25 and 26  wherein movement of a pipe length along pipe alignment frame  69  is unrestricted and an “up” position, shown in  FIG. 27  in response to the extension and retraction of retainer ram  81 , wherein movement of rearward pipe length RP is restricted.  
         [0051]     Referring to  FIGS. 28-30 , bell divot system  75  is shown connected to alignment frame forward section  63  in front of skid  62 . V-roller  65 E is also shown attached to alignment frame forward section  63 . Bell divot system  75  includes divot ram  78  attached at a first end pipe to alignment frame forward section  63  and at a second end to linkage  76 , which connects to a divot cutter  79 . Divot cutter  79  pivots on shaft  77  with extension and retraction of divot ram  78  and linkage  76 . Bell divot system  75  is adapted to selectively excavate a depression in the floor of the trench at a point at which a bell section of a pipe length is to ultimately lie on the floor of the trench. Divot cutter  79  is selectively positioned between a “travel” position, as seen in  FIG. 28 , and a “dig” position as seen in  FIG. 29 . Divot cutter  79  is usually positioned in a “travel” position, as seen in  FIG. 28  wherein divot cutter  79  does not make contact with the floor of the trench. Referring to  FIG. 12 , as pipe alignment system  60  moves in a forward direction indicated by the reference figure “D”, bell section B of rearward pipe length RP, passes over bell divot system  75 , divot ram  78  retracts and divot cutter  79  is moved to the “dig” position, shown in  FIG. 29 , where it remains for approximately 45 cm, (approximately 18 inches), of travel to excavate a divot that measures approximately 15 cm, (approximately 6 inches), wide by 45 cm, (approximately 18 inches), long into which bell B will lie when it ultimately comes to rest on floor F.  
         [0052]     Referring to  FIGS. 9-12 , operation of pipe restraint system  80  and pipe joining system  70  will be described in detail. Once rearward pipe length RP has passed pipe passage sensor  141 , as shown in  FIG. 9 , forward travel of pipe installation device  10  is suspended. When sensor  143 , senses the release of forward pipe length FP, controller  140 , shown in  FIG. 32 , retainer ram  81  of pipe restraint system  80  retracts lifting retainer forks  82  and  83 , as shown in  FIG. 109  shown in  FIGS. 26 and 27 , pivoting retainer forks  82  and  83  on shaft  85  between a “down” position, shown in  FIG. 26 , to an “up” position,  FIG. 27 . Once forward pipe is lowered onto pipe alignment frame  69  as seen in  FIG. 9 , forward pipe length FP and rearward pipe length RP are aligned longitudinally. When forward pipe length FP is lowered onto pipe alignment frame  69 , sensor  144  is tripped, as shown in  FIG. 9 , and operation of winches  43  and  44  continue for a preset time period to allow straps  41  and  42  to be lowered well below forward pipe length FR as seen in  FIGS. 9-11 . Also when sensor  144 , is tripped operation of pipe joining system  70  is initiated and, as seen in  FIG. 23 , joining ram  71  retracts forcing push plate  72  against forward pipe length FP, as shown in  FIG. 11 , joining forward pipe length FP to the restrained rearward pipe length RP. Joining ram  71  includes a limit switch  145 , shown in  FIG. 32 , that may be adjusted to control the extension of joining ram  71 . In this manner, insertion depth of a spigot end of forward pipe length FP into the bell end of the restrained rearward pipe length RP may be accurately set and controlled for various pipe sizes.  
         [0053]     Once joining ram  71  reaches the outer limit of its preset extension, limit switch  145 , shown in  FIG. 32 , is tripped and extension of joining ram  71  is initiated until limit switch  146 , shown in  FIG. 32 , is tripped providing an output that joining ram  71  has reached full retraction and joining ram  71  is de-energized. The output from limit switch  145 , shown in  FIG. 32 , that joining ram  71  has reached full extension prompts controller  140 , shown in  FIG. 32 , to initiate extension of retainer ram  81 , shown in  FIGS. 26 and 27 , pivoting retainer forks  82  and  83 , retainer fork  83  shown in  FIG. 12 , on shaft  85  from the “up” position,  FIG. 27  to the “down” position, shown in  FIG. 26 . The output from limit switch  145 , shown in  FIG. 32 , that joining ram  71  has reached full extension also prompts controller  140 , shown in  FIG. 32 , to signal the resumption of travel of pipe installation device  10  in direction D along a course of pipeline construction C, as shown in  FIG. 12 . Output from limit switch  145 , shown in  FIG. 32 , that joining ram  71  has reached full extension also prompts controller  140 , shown in  FIG. 32 , to initiate retraction of divot ram  78  moving divot cutter  79  from a “travel” position, seen in  FIG. 28 , to a “dig” position as seen in  FIG. 29 . An output from sensor  144 , indicating that forward pipe length FP has moved beyond sensor  144 , as shown in  FIG. 12 , prompts controller  140 , shown in  FIG. 32 , to initiate extension of divot ram  78  moving divot cutter  79  from the “dig” position as seen in  FIG. 29 , to the “travel” position, seen in  FIG. 28 .  
         [0054]     Referring to  FIG. 31 , carriage  11  is shown including frame  15  which supports power and control systems housing  16 . Frame  15  is shown in a top cutaway format to illustrate certain features of steering system  100  and drive system  110 . In the preferred embodiment of the invention, carriage  11  is steered by steering system  100 . Steering system  100  includes head plate  105  pivotably attached at a first end of axle  13  and head plate  106  attached at a second end of axle  13 . Link arm  103  is also pivotably attached between head plates  105  and  106 . Hydraulic steering ram  101  is connected at a first end to axle  13  and at a second end to link arm  103 . Similarly, head plate  107  pivotably is attached at a first end of axle  14  and head plate  108  is attached at a second end of axle  14 . Link arm  104  is also pivotably attached between head plates  107  and  108 . Hydraulic steering ram  102  is connected at a first end to axle  14  and at a second end to link arm  104 . Steering rams  101  and  102  extend and retract in response to an output from a controller  140 , shown in  FIG. 32 , as more fully discussed herein below.  
         [0055]      FIG. 31  also shows carriage  11  driven by four hydraulic planetary speed reducing motors  111 - 114 , one connected at head plate  105 - 108  respectively, to which wheels  12 A- 12  D are mounted respectively. Hydraulic power is applied at each of the hydraulic planetary speed reducing motors  111 - 114  as discussed herein below.  
         [0056]      FIG. 32  is a representative schematic diagram showing features of power system  120  and control system  130 . In the preferred embodiment, power system  120  includes engine  121 , generator  122  and hydraulic pump  123  connected to hydraulic reservoir  124 . Control system  130  includes solenoid operated control valves  131 - 138 , sensors  141 - 147  and controller  140 . Control system  130  may also include a remote control device, not shown, that permits an operator to control functions of the pipe installation device including “on-off”, travel, stop, energize feed system, energize pipe joining system and “kill.” As shown, control system  130  includes the following solenoid operated control: 
        a) Control valve  131 , a 3-position 4 way solenoid operated control valve, controls forward travel by regulating flow to hydraulic planetary speed reducing motors  111 - 114 . As seen in  FIG. 32 , forward travel circuit  148  includes flow divider  156  that assures that power applied to front hydraulic planetary speed reducing motors  113  and  114  and rear hydraulic planetary speed reducing motors  111  and  112  is substantially equal.     b) Control valve  132 , a 3-position 4 way solenoid operated control valve, controls flow to front steering ram  101 .     c) Control valve  133 , a 3-position 4 way solenoid operated control valve, controls flow to rear steering ram  102 .     d) Control valve  134 , a 2-position solenoid operated control valve, controls operation of release ram  36 .     e) Control valve  135 , a 3-position 4 way solenoid operated control valve, controls flow to winches  43  and  44 .     f) Control valve  136 , a 2-position solenoid operated control valve, controls operation of joining ram  71 .     g) Control valve  137 , a 3-position solenoid operated control valve, controls operation of bell retainer ram  81 .     h) Control valve  138 , a 2-position solenoid operated control valve, controls operation of divot ram  78 .          
         [0065]     Control system  130  also includes sensors  141 - 152  as follows: 
        a) Sensor  141 , a pipe passage sensor  141 , an optical sensing device including a laser optical emitter, a reflector and an optical sensor that provides input to control system  140  indicating that a pipe length has advanced beyond pipe passage sensor  141  on pipe alignment frame  69 , as shown in  FIG. 9 .     b) Sensor  142 , a limit switch that is tripped when winches  43  and  44  have fully retracted first and second straps  41  and  42  of pipe feed system  40 , as seen in  FIGS. 4 and 5 .     c) Sensor  143 , a limit switch, is tripped when a length of pipe is released from pipe supply rack  20  into pipe feed system  40 , as seen in  FIGS. 6-8 .     d) Sensor  144 , an optical sensing device including a laser optical emitter, a reflector and an optical sensor that senses when a pipe length has been lowered onto pipe alignment frame  69  by pipe feed system  40 , as seen in  FIGS. 9 and 10 .     e) Sensor  145 , a limit switch that is tripped when joining ram  71  is at a fully extended position, indicating that a forward pipe length has been joined with the rearward pipe length, as seen in  FIG. 11 .     f) Sensor  146 , a limit switch that is tripped when joining ram  71  is at a fully retracted position, as seen in  FIG. 12 .     g) Sensors  147  and  148 , limit switches located in angular motion sensor  55  and are tripped by the angular displacement of sidewall contact paddle sidewall contact paddle  53 , shown in  FIG. 1 .     h) Sensors  149  and  150 , limit switches associated with axle  13  which are tripped when wheel  12 A or  12 B are angulated to the right or left, as seen in  FIG. 31 .     i) Sensors  151  and  152 , limit switches located in angular motion sensor  56  which are tripped by the angular displacement of sidewall contact paddle  54 ,  54 , as shown in  FIGS. 2 .     j) Sensors  153  and  154 , limit switches associated with axle  14  which are tripped when wheel  12 C or  12 D are angulated to the right or left, as seen in  FIG. 31 .        
 
         [0076]     Referring to  FIGS. 33A and 33B , a schematic flow diagram depicts a flow or sequence of operation of pipe installation device  10 . At step  200 , INITIATE OPERATION OF PIPE INSTALLATION DEVICE, operation of pipe installation device  10  is initiated. At step  201 , IS PIPE IN ALIGNMENT SYSTEM FORWARD SECTION, controller  140  queries to determine that pipe passage sensor  141  does not sense a reflected signal indicating a pipe length is currently positioned upstream of pipe passage sensor  141 , as shown in  FIG. 12 . Referring to  FIG. 33 , at step  202 , OPERATE DRIVE SYSTEM, control valves  131  and  132  are energized causing rotation of hydraulic planetary speed reducing motors  111 - 114 , shown in  FIG. 32 , initiating forward motion of pipe installation device  10 . In the event that pipe passage sensor  141  senses a reflected signal indicating that rearward pipe length RP has passed pipe passage sensor  141 , as shown in  FIG. 9 , referring to  FIG. 33 , at step  2034 , SUSPEND DRIVE SYSTEM OPERATION, control valves  131  and  132 , shown in  FIG. 32 , are de-energized and forward motion of pipe installation device  10  is suspended. At step  204 , MOVE RESTRAINT ARMS TO UP POSITION, control valve  137 , shown in  FIG. 32 , is energized and bell retainer ram  81  retracts raising retainer forks  82  and  83 , as shown in  FIG. 27  and rearward pipe length RP is restrained against rearward movement. Referring to  FIG. 33 , at step  205 , RETRACT PIPE LAYDOWN STRAPS, control valve  134 , shown in  FIG. 32 , is energized and first and second straps  41  and  42  are retracted as seen in  FIG. 5 . Referring to  FIG. 33 , at step  206 , STOP WINCHES, sensor  142 , sense that first and second straps  41  and  42  are retracted as, shown in  FIG. 5 , and control valve  134 , shown in  FIG. 32 , is de-energized.  
         [0077]     Referring to  FIG. 33 , at step  207 , INITIATE OPERATION OF PIPE RELEASE SYSTEM, control valve  135 , shown in  FIG. 32 , is energized, and release ram  36  retracts moving outer release arms  31  and  32  from a generally vertical orientation to a horizontal orientation and inner release arms  33  and  34  from a generally horizontal orientation to a vertical orientation, as shown in  FIGS. 16-19  releasing forward pipe length FP, which rolls down inclined ramps  21  and  22  and is caught by first and second straps  41  and  42 , as seen in  FIGS. 7 and 8 . Referring to  FIG. 33 , at step  208 , SENSE PIPE LENGTH RELEASED, sensor  143 , shown in  FIG. 32 , is tripped as forward pipe length FP rolls down inclined pipe ramp  21 . Referring to  FIG. 33 , at step  209 , INITIATE PIPE LOWERING, shown in  FIG. 32 , control valve  134 , shown in  FIG. 32 , is energized and first and second straps  41  and  42  are extended and forward pipe length FP is lowered onto pipe alignment system  60 , as seen in  FIG. 9 . Referring to  FIG. 33 , at step  210 , SENSE PIPE LENGTH IN FORWARD SECTION OF PIPE ALIGNMENT SYSTEM, sensor  144 , shown in  FIG. 32 , senses that forward pipe length FP has been lowered onto pipe alignment frame  69  of pipe alignment system  60 , as seen in  FIG. 9 .  
         [0078]     Referring to  FIG. 33 , at step  211 , ENERGIZE PIPE JOINING SYSTEM, control valve  136 , shown in  FIG. 32 , is energized extending joining ram  71 , as seen in  FIG. 11 , joining forward pile length FP to rearward pipe length RP. Referring to  FIG. 33 , at step  212 , SENSE FULL RETRACTION OF JOINING RAM, sensor  145 , shown in  FIG. 32 , is tripped when joining ram  71  is at a fully extended position, as seen in  FIG. 11 , indicating that a forward pipe length FP has been joined with the rearward pipe length. Referring to  FIG. 33 , at step  213 , RETRACT PIPE JOINING RAM, control valve  136 , shown in  FIG. 32 , is energized for opposite travel retracting joining ram  71 , as seen in  FIG. 12 . Referring to  FIG. 33 , at step  214 , SENSE JOINING RAM RETRACTED sensor  146 , shown in  FIG. 32 , is tripped when joining ram  71  is at a fully retracted position, as seen in  FIG. 12 . Referring to  FIG. 33 , at step  215 , MOVE RESTRAINT ARMS TO DOWN POSITION, the second circuit of control valve  137 , shown in  FIG. 32 , is energized and bell retainer ram  81  is extended moving bell retainer arms  82  and  83  to the down position as seen in  FIGS. 25 and 26 .  
         [0079]     Referring to  FIG. 33 , at step  216 , RESUME DRIVE SYSTEM OPERATION, control valves  131  and  132  are re-energized causing rotation of hydraulic planetary speed reducing motors  111 - 114 , shown in  FIG. 32 , resuming forward motion of pipe installation device  10 . Referring to  FIG. 33 , at step  217 , MOVE DIVOT CUTTER TO DIG POSITION, after a pre-set period of time, control valve  138 , shown in  FIG. 32 , is energized and divot ram  78  retracts moving divot cutter  79  to the dig position for a pre selected period of time as shown in  FIG. 12 . Referring to  FIG. 33 , at step  218 , RETRACT DIVOT CUTTER TO TRAVEL POSITION, after a pre-set period of time, control valve  138 , shown in  FIG. 32 , is energized and divot ram  78  extends moving divot cutter  79  to the travel position as shown in  FIG. 28 . Forward travel continues until pipe passage sensor  141  senses a reflected signal indicating that rearward pipe length RP has passed pipe passage sensor  141 , as shown in  FIG. 9 , at which point the sequence returns to step  203 , SUSPEND DRIVE SYSTEM OPERATION.  
         [0080]     While this invention has been described with reference to the detailed embodiments, it s not intended that this description be construed in a limiting sense. Various modifications to the described embodiments, as well as additional embodiments of the invention, will be apparent to persons skilled in the art upon reference to this description. It is therefore contemplated that the appended claims will cover any such modifications or embodiments as fall within the true scope of the invention.