WO2000000322A2

WO2000000322A2 - Internal space clamp

Info

Publication number: WO2000000322A2
Application number: PCT/US1999/014499
Authority: WO
Inventors: William David Parker
Original assignee: Sabre International, Inc.
Priority date: 1998-06-26
Filing date: 1999-06-25
Publication date: 2000-01-06
Also published as: AU4835399A; WO2000000322A3

Abstract

An internal spacer clamp for use in welding one end of a pipe to an end of a second pipe. This includes a first spider ring (26) having a first set of pipe contacting pistons for engaging the interior of the first pipe and supported from a frame. A second spider ring (28) having a second set of pipe contacting pistons for engaging the interior of pipe. There is a first power piston (135) for driving each of the pistons in said first spider ring (26) in or out of its hole and a second power piston (38) for driving each said piston in the second spider ring (28) in and out. An air powered pipe spacing power piston (68) supported adjacent said second power piston (38) for moving the second spider ring (28) toward or away from the first spider ring (26). The housing of the spacing power piston is rigidly connected to the housing of the second power piston which is rigidly connected to a cup-like cover which connects the housing of the second power piston to the second spider ring whereby movement in or out of the spacing housing moves the second spider ring either toward or away from the first spider ring. Control air valves control the sequence of pressurized air being supplied to drive the pistons of the power pistons in or out in a selected order.

Description

INTERNAL SPACER CLAMP

BACKGROUND OF THE INVENTION:

This invention relates generally to internal pipe clamps useful in welding joints of pipe together. Pipelines are laid extensively across the United States and other parts of the world in order to convey fluids or other material from one location to another. In the building of these pipelines numerous joints are laid end to end and welded together to form a conduit of the desired length and at the proper location. These joints of pipe are usually made of steel and can be anywhere from twelve inches to sixty inches or more in diameter and up to sixty or eighty feet in length.

The ends of adjacent pipe joints are welded together. The ends of these sections of pipe must be held during the welding operation. It is usually desired to have a space or gap between the two end sections of the pipe in order to obtain proper welding. Internal welding clamps are generally used for this purpose. A frame supports a first spider ring and a second spider ring which are parallel to and spaced from each other. Each spider ring contains a plurality of radial holes therein and in which each hole contains a radial piston which when activated extends or retracts radially through the spider ring. The outer end of these pistons contain a shoe or pad which contacts the inner surface of the pipe. One spider ring is in one section of pipe and the other in the other section, each near the ends of the pipe to be welded. By applying sufficient pressure to these pads on each spider ring the pipes are held in substantially fixed relationship with each other. The pressure is normally obtained from high pressure cylinder run by high pressure air and regulated by electrically operated valves. Welding operations may proceed. Pipe clamps are commercially available.

However, the presently available pipe clamps do not provide adequate and/or efficient means for obtaining and maintaining the desired gap between the ends of the pipe to be welded.

It is therefore an object of this invention to provide an internal spacing clamp whereby the desired gap can be quickly obtained and held in position.

It is another object of this invention to provide a mechanical means for controlling the air under pressure to the various pistons.

SUMMARY OF THE INVENTION:

This internal spacer clamp includes a frame having a disc-like member or support plate which when installed in the pipe will be perpendicular to the pipe. This support plate supports a first spider ring in a fixed relationship thereto. It also supports a second spider ring which has limited axial movement with respect to the support plate. The two spider rings are parallel to each other. Each spider ring contains a plurality of radial holes. An anchor piston is in each hole for radial movement and each piston has an inner end and an outer end. The outer end of the anchor piston is provided with a pad contoured to mate with the interior surface of the pipe when the piston is at its outermost extended position.

A main support shaft extends perpendicularly to the support plate on each side thereof. A first anchor piston power cylinder is provided on one side of the support disc. This first cylinder is to power the extension and retraction of the anchor piston in the first spider ring. This first power cylinder has a piston and piston rod which has axial movement on and supported by the extension of the shaft extending beyond the support plate. Power means such as air under pressure is provided selectively to either side of the piston within the housing of the first power cylinder to move the piston in selected axial direction. The movement of the piston rod causes the spider ring piston to be extended to or retracted from the interior of the pipe to be welded.

On the other side of the support plate from the first power cylinder is a second power cylinder which has a housing and a piston therein and is similar to the first power cylinder in that it is used to extend or retract the piston in the second spider ring. The piston is sealingly and slidably mounted on the support shaft. Selectively supplying pressured air to either side of the second power cylinder causes the piston to move either toward or away from the support plate. This movement causes the pistons of the second spider disc to be either extended or retracted. I shall now briefly discuss that part of the clamp for moving the second spider ring axially for spacing the selected distance between the two pipes to be welded. A spacing piston is mounted on the outer end of the main support shaft. This main support shaft sealingly extends through the housing of the second power cylinder. A spacing housing encloses the spacing piston and is movable axially in relation thereto. This makes up a pipe positioning power member. There is a port in the spacing housing on either side of the spacing piston. A cup-like cover surrounds the second piston rod in a sliding and sealing relationship therewith. The base of the cup-like member is connected to the housing of the second power cylinder and the rim of the cup cover is rigidly attached to the second spider ring. The spacing housing of the second spider ring positioning member is rigidly attached to the housing of the second power cylinder which is attached to the cover enclosing the second piston rod. The rim end of the cup is attached to the second spider ring. Thus, the spider ring is rigidly connected to the cover housing which is rigidly connected to the housing of the second cylinder which is connected to the spacing housing of the pipe positioning members cylinder. Thus, movement of the spacing housing of the pipe positioning member axially moves the second spider ring. The axial movement of this housing then causes axial movement of the second spider ring and when the pistons of the second spider ring are extended, this movement moves the second joint of pipe.

In operation this spacing clamp is inserted into the end of a first pipe and the pistons of the first spider ring contacts the walls in the vicinity of the end thereof. Then a second pipe is placed over the other end of the spacer clamp and into proximity of the end of the other pipe which was being held by the first spider ring. The ends of the two pipe are then positioned in contact with each other.

Before the second end of the pipe was mounted over the spacing clamp a spacing control which limits the axial movement of one spider ring with the second spider ring is then set. The pistons in the second spider ring are activated to grab the inner wall of the second joint of pipe. Then the pipe positioning pistons are activated to move the housing away from the support plate. Movement in one direction moves the end of the pipe into contact with each other. A stop is provided to limit the movement of the second spider ring with respect to the first spider ring. This limiting controls the amount of spacing obtained. After the limiting stop has been set, the spacing cylinder is activated to move the second spider ring the set distance away from the first spider ring. This moves the end of the second pipe the same distance from the end of the first pipe. The pipe is then ready for welding with the proper spacing which will be held in that position until the weld is finished.

Other objects and a better understanding of the invention may be had from a description which follows in relationship with the drawings in which:

BRIEF DESCRIPTION OF THE DRAWINGS:

FIGURE 1 is a side elevation schematic view of the spacing clamp of the present invention disposed in a pipe in the vicinity of the ends of the pipe to be welded; FIGURE 2 shows an unactivated spacing clamp, mostly in section, located at the end of the first pipe with the second joint of pipe omitted;

FIGURE 3 is similar to Figure 1 except that the first pipe (on the left) is held by activation of the pistons of the first spider ring and a second pipe has been moved over the right hand side of the clamp to where it is in the proximity of the first pipe, in this view the second pipe is not held by the spacing clamp;

FIGURE 4 is similar to Figure 3 except that the holding pistons on the spider ring on the right hand side has been extended to have a "soft" chuck with the second joint of pipe.

FIGURE 5 is similar to Figure 4 except that the right hand pipe has been moved into contact or abutment with the pipe on the left side by movement of the right hand spider clamp by activation of the pipe spacing cylinder;

FIGURE 6 is similar to Figure 5 except this is the next sequence in which the spider ring power piston has been activated to move the second pipe (on the right) a distance to obtain the desired gap between the ends of the pipes; FIGURE 7 is a schematic diagram of the air control system for operating the pneumatic cylinders for setting the pistons and pads and for spacing the two pipes;

FIGURE 8 illustrates a control tool for operating air valves to control sequence of operation; FIGURE 9 is a view taken along the lines 9-9 of Figure 8;

FIGURE 10 is similar to Figure 8 except that the left end of the operating tool has been moved so that arms on the left end contact certain valves to operate them;

FIGURE 11 is a view taken along the line 11-11 of Figure 10; FIGURE 12 is similar to Figure 8 except that the right-hand portion of the operating tool has been moved to the right to operate another set of valves;

FIGURE 13 is a view taken along the line 13-13 of Figure 12;

FIGURE 14 is a view partially in section of the modified end or head of a reach rod;

FIGURE 15 is similar to Figure 14 except that the head has been rotated ninety degrees;

FIGURE 16 is a front view of the rod in Figure 15;

FIGURE 17 shows the connector of the tool shown in Figure 9 as it is about to enter the connecting head of the reach rod;

FIGURE 18 shows a connector in the cavity of connector head of the reach rod;

FIGURE 19 is similar to Figure 18 except that the reach rod has been rotated ninety degrees so that the connector pin enters the internal enlarged diameter so that it contacts shoulders of the reach rod head and is useful in pulling on the connector pin of the control unit;

FIGURE 20 is a view taken along the lines 20-20 of Figure 19;

FIGURE 21 is a view similar to that of Figure 20 except that the connector tool of the control unit is in a midpoint between the pull position and the push position and is aligned axially with the enlarged internal diameter;

FIGURE 22 is a view taken along the line 22-22 of Figure 21 ;

FIGURE 23 is similar to Figures 19 and 21 except that the pins of the connector rod is against the shoulders of the right hand side of the cavity so that it is useful for pushing; FIGURE 24 is a view taken along the line 24-24 of Figure 19;

FIGURE 25 is similar to Figure 24 except that the connector extension has been rotated to the right;

FIGURE 26 is similar to Figure 25 except the tool connector has been rotated to the left to contact a different air control valve; FIGURE 27 is a view of another embodiment of the pressure control tool for operating air valves to control sequence of operation;

FIGURE 28 is a view similar to that of Figure 27 except that the finger of the control tool has been moved to the right.

DETAILED DESCRIPTION:

Attention is first directed to Figure 1 which shows schematically the spacing clamp of this invention mounted inside pipe formed by the first joint 10 and a second joint 12 with a beveled groove 14 therebetween. In the right hand section of the pipe is a framework 16 having rigid bars 18 and a nose piece or connecting nose 20. The description of the nose piece will be made later. Also shown are parallel support rings 22 and 24 to which is mounted first spider ring 26 and second spider ring 28, respectively. First spider ring 26 has a plurality of pads 30 for pushing against the pipe and second spider ring 28 likewise has a plurality of pads 32. A support plate 34 is placed between the two spider rings

26 and 28. Spider ring 26 is fixed to this support disc 34. However, second spider ring 28 is supported from the support disc 34 in a limited axially slidable connection. A pad setting air cylinder 36 is shown, and will be described later, acts to extend or retract the piston supporting the pads 30 of spider ring 26. These pads are shown in the extended position. Second spider ring 28 has pads 32 which are extendable and retractable by activating second pad setting air cylinder 38. A pipe moving or spacing air cylinder 40 is also shown. Activation of this air cylinder 40 causes second spider ring 28 to move toward or away from support plate 34. Support plate 34 is supported from rings 22 and 24 in any well known manner such as by bolts or welding. Rings 22 and 24 are a part of the main frame of the tool which are connected by various means to bars 18 and 18A.

A drive wheel 42 is supported from brackets 44 and is driven by air cylinder 46. Also supported from the frame are support wheels 48 and 50. These are used in the conventional manner for rolling the tool in or out of pipe.

Also shown is an air tank 52. To briefly recapitulate it is seen that pad setting air cylinder 36 will extend or retract the pads 30 of spider ring 26 whereby the pads will either be in contact or out of contact with the interior wall of pipe 10. Also, second pad setting air cylinder 38 when activated will push in to extend or retract pads 32 so they are either in contact or out of contact with the interior wall of pipe section 12. Activation of pipe spacing air cylinder 40 moves the pipe section 12 either toward or away from section 10.

Attention is next directed to Figure 2 which shows the basic components of the spacing clamp of this invention. I shall first discuss that portion of the clamp which is to the left of the support plate 34. In this Figure the clamp has been positioned in the first pipe section 10 in a manner such that the center line of the support plate 34 is aligned with the end of pipe 10. The second pipe 12 has not been placed in position in this Figure. Spider ring 26 is supported from support plate 34 by bolts 170. Although there is only shown one such bolt there should be any reasonable number such as three or four or whatever is preferred and normally be spaced evenly about the spider ring 26. Pistons 178 with pads 180 extends through the plurality of holes in the spider ring 26. A first pad setting air cylinder 135 includes a housing 138, piston 130, piston rod 134 and hub 154 which is connected to piston rod 134. A shaft 54 extends perpendicular through support plate 34 and is fixed thereto such as by welding. The left end of shaft 54 has a shaft extension 56 which extends into cylindrical cavity 136 in piston rod 134 which is attached to piston 130. A bushing 158 is provided between the shaft extension 56 and the piston rod 134. Piston rod 134 is fixed to the piston 130 by bolt and nut arrangement 133. Housing 138 is provided with a first and second port 140 and 142 which are on either side of the piston 130. Stops 132 prevent the piston 130 from extending to the left in a manner to block port 140. The hub 154 is enclosed by a cover 144 which is connected to housing 138 by a bolt 146 which extends through shoulder 148 of the housing 138. Piston rod 134 extends through the center of the base of cover 144 and seal 175 is held in position by support 162 which is held to the cover 144 by bolts 164. The end of piston rod 134 opposite the piston 130 is provided with a hub 154. The hub 154 is connected to link 152 by pin 153 and link 152 is connected to piston 178 in spider ring 26 by pin 155. In the device of Figure 2, in this stage the air pressure is provided through port 142 to piston 130 so that the piston 130 is driven to the left and has links 152 in the position shown. This removes the pad 180 from contact with the wall of the pipe. As shown in Figure 3, when it is desired to have the pads 180 contact the wall, the pressure is applied through port 140, the piston 130 moves to the right and forces the spider ring piston 178 outwardly until the pads are in firm contact with the inner wall of pipe 10. Of course when it is desired to release the pad 180 from contact with the pipe 10 air pressure is applied through port 148 as indicated in Figure 2. Attention will now be directed to that part of the clamp which is to the right of support plate 34. This includes a second pad setting power cylinder 38 which includes housing 70 which is connected to shoulder 104 by bolt 106 of cover 92 which is a cup shaped or bowl shaped member which has a base 71 and a rim including rim arm 120. Arm 120 is connected to spider ring 28 by bolts 122. A piston 84 having seals 86 is positioned in the housing of second pad setting cylinder 38 and is provided with a piston rod 72 which is supported by bearing

81 from shaft 54. Also, seals 98 are provided between the piston rod 72 and the shaft 54. The left end of piston rod 72 is provided with a hub 78. A pin 118 connects the piston hub 78 to link 116 which in turn is connected to pin 114 to piston 112 in the second spider ring 28. The outer end of piston 112 is provided with a pad 32 for contacting the inner wall of the pipe. Thus, if pressure fluid is provided to port 80 as indicated in Figure 2, the piston 84 moves to the right and the link 116 is in the position shown in Figure 2 and the pads 32 are completely removed from the inner wall of the pipe. If it is desired to force the pads 32 against the inner wall of the pipe the pressure is applied through port 81 to drive the piston to the position shown in Figure 4.

I shall now discuss that portion of the device on the right hand side of support plate 34 which is used for moving the spider ring 28 to the right when the piston 112 and pad 32 are in the position shown in Figure 6 to provide space 205 between pipes 10 and 12. This spacing apparatus includes a piston 68 secured to the right extension end of shaft 54 by nut 62 and bolt 60. There is also a seals 64 and 66 provided for the piston as shown. Piston 68 is in housing 39 of the pipe spacing cylinder 40. Housing 39 is provided with a first shoulder 100 which connects the housing 39 to the housing of the second pad setting cylinder 38. A port 74 extends through the shoulder 105 to the left side of piston

68. There is a second port 76 in the housing 39 which provides fluid inside the housing to the right of piston 68. Housing 39 is fixed to housing 38 which in turn is fixed to cover 92 which is fixed to spider ring 28. Thus, housing 39 is rigidly attached to spider ring 28. Thus, movement of cylinder housing 39 as fluid is selectively applied through either port 74 or port 76 will cause the spider ring 28 to move either toward or away from support plate 34 such that piston 112 and pads 32 can be selectively extended or retracted.

I shall now discuss that part of the apparatus in Figure 2 which limits the amount of axial movement that spider ring 28 can make with respect to first spider ring 26 which is rigidly attached to the support plate 34. This includes a bolt 200 which extends through holes in spider ring 26, support plate 34 and spider ring 28. A nut 202 on the left end of bolt 200 holds the bolt in the hole of spider ring 26. Other means for holding the bolt within the space as shown in Figure 2 could be used. Bolt 200 extends through unthreaded holes in spider ring 26, support plate 34 and spider ring 28. The right end of bolt 200 is provided with an adjustment nut 124. The setting of this adjustment nut 24 along bolt 200 determines the amount of movement that the spider ring 28 can make to the right from support plate 34 which is the same as determining amount of movement spider ring 28 can make with respect to spider ring 26. As spider ring 26 is secured to pipe 10 by pads 180 and spider ring 28 is secured to pipe 12 by pads 32, the movement of spider ring 28 from ring 26 moves pipe 12 the same movement or distance from pipe 10. As shown in Figure 3 there is a space or gap 210 between ends 10A and 12A. This space will be the desired spacing of the gap 210 between pipes 10 and 12. I shall now discuss the positioning of the pipe and the steps taken with the device just described to obtain the proper spacing between the two pipes 10 and 12. I shall make this discussion in connection with Figures 2 through 6 which illustrates sequence A through E, respectively. Figure 2 shows sequence A where the clamp of this invention has been positioned in the first pipe and the center of the support plate 34 is aligned with the end of pipe 10. This alignment can be obtained by proper manipulation of drive wheels 42 to drive the clamping tool along the inside of pipe 10 to the desired position. In this sequence A neither the pistons 178 of spider ring 26 nor the pistons 112 in spider ring 28 have been extended. In other words, none of these piston pads 180 or 32 is in contact with the interior wall of the pipe.

I next refer to Figure 3 to illustrate sequence B. There the first pipe 10 is held in position and the second pipe 12 has been moved over the right hand side of the spacing clamp which extends out of pipe 10. The end 12A of pipe 12 is moved to the proximity of the end 10A of pipe 10. Typically this may be within a distance of about 1/16 inch or less of each other. One normally wants the pipes to be as close as possible. Before the pipe 12 is brought into position, air under high pressure for example 250 psi or more, depending somewhat on the size of the pipe is injected through port 140 into first piston setting power cylinder 136. This drives the pistons 130 and hub 154 and link 152 from the position shown in Figure 2 to a position shown in Figure 3. In this position the pad 180 is "hard chucked" against the inner wall of pipe 10. Thus pipe 10 is held in position with respect to the interior pipe clamp. During this sequence and the prior sequence A, air under pressure is supplied to port 80 in the second piston setting power cylinder 38. This keeps the pistons 112 in their retracted position as shown both in Figures 2 and 3.

Attention is next directed to Figure 4 which illustrates sequence C. The spider ring pistons 178 are in the position as shown in Figure 3 and held in "hard" chuck against the interior wall of pipe 10. This means that the pads are pressed so firmly against the pipe 10 that they are held together during the various sequences discussed herein. Pressure is applied to port 81 to drive the pistons 84 and accompanying hub 78 into the position shown in Figure 4. This pressure which is applied is lower than the pressure applied to first piston or pad setting power cylinder 36 as was applied to it in the sequence step of Figure 3.

Typical pressure of air supplied through port 81 , in this stage of operation, is in the range of about 23 to 40 p.s.i. This lower pressure will extend the pistons 112 to force pad 32 in what is called a "soft" chuck against the interior of the pipe 12. It is understood that these pressure are illustrative and any pressure that will accomplish the objective can be used depending upon the engineering designs and so forth.

Attention is now directed to Figure 5 to illustrate sequence D. This sequence is to move the end 12A of pipe 12 into contact with the end 10A of pipe 10 from the position shown in Figure 4. This is accomplished by applying pressure through port 74. Inasmuch as piston 68 of the spacing piston housing is held in fixed position by its attachment to shaft 54 the spider ring 28 is moved to the left. Inasmuch as the spider ring has itself chucked against the inner wall of pipe 12, pipe 12 will move with it until it reaches the contact position shown in Figure 5. The force is applied to spider ring 28 when pressurized fluid is forced through port 74. This forces the housing of piston cylinder 38, cover 92 and spider ring 28 (all attached) to the left. This moves pipe end 12A into contact with pipe end 10A as shown. Power is continually applied through port 74 and the pads 32 may slide slightly with respect to the pipe 12 to permit the pipe spacing cylinder 40 to obtain its full moment to the left. As shown in Figure 5 the pipes have been abutted and the next step is to activate the spacing cylinder 40 to obtain the desired spacing 210 between the pipes. In this regard attention is next directed to Figure 6 to explain sequence E. Before pipe 12 was placed over the device, the device was as shown in Figure 2. At that time the adjustment nut 24 was adjusted along bolt 200 to obtain a space 203 as shown in Figure 5. This space 203 will be set at the same dimension as the desired spacing as the space 210 between the pipe ends 10A and 12A as shown in Figure 6. At this point the pistons 112 and pads 32 needs to be "hard" chucked against inner wall of pipe 12. This is so that pads 32 will grip the pipe very firmly. This is accomplished by applying air under pressure to port 81 to drive piston 84 to the left so that hub 78 pushes the piston 112 outwardly with a greater force than on the previous "soft" chuck. This can be accomplished by a very small amount of rotation of link 116 about pin 114. This high pressure will force the link 116 about pivot 114 to move it slightly which will cause greater force to be applied on piston 112 and pad 32 to force the pad into what is called a hard chuck condition. Now I am at the point where the pipe can be moved to the right to obtain the desired spacing 210. The next step is to apply high pressure fluid, for example 250 p.s.i. through port 76 or whatever pressure is required to effect this movement. Inasmuch as piston 68 is attached to the shaft 54 which is stationary, piston 68 does not move. The movement of the housing of spacing cylinder 40 moves to the right and as it does it moves the spider ring 28 also to the right inasmuch as it is attached firmly to it by the housing of piston setting cylinder 38 and cover 92. When shoulder 207 (see Figure 5) contacts spacing nut 124, movement of the pipe and spider ring 28 stops. Because of the setting of the adjustment nut 124 the second pipe 12 will be moved a distance or space as set by the spacing nut to obtain the desired spacing 210. This is now the proper spacing for welding. Welding operations can now begin. When the welding operation is complete, the pressure can be applied to port 142 of first piston setting cylinder 138 and through port 80 of second piston setting cylinder 38. This drives respectively the piston 130 to the left and piston 84 to the right which acts on the pistons 178 and 112 to withdraw them to the position shown in Figure 2. Now the tool can be withdrawn and used to weld the next joint.

Attention is next directed to Figure 7 which shows in simplified schematic form a control air diagram for controlling the inlet and outlet air to the first piston setting power cylinder 138 on the left side of the drawing of Figure 2 and also inlet and outlet air to the second piston setting cylinder 38 and to the inlet and outlet of the cylinder 40. Shown in Figure 7 is an air control tool 372 which is shown in detail in

Figures 8, 9, 10, 11 , 12, 13, 14 and 15. As shown in Figure 9, it is supported by rigid bars 18 connected to section 301. This includes an attachment 400 (Figure 19) which is attached to a reach rod 402 which are normally straight long steel rods. Reach rods are quite common in the pipelaying business. A configuration of the reach rod head that attaches to connecting nose piece 310 will be explained with Figures 8, 9, 10, 11 to 23. At the outer end of tool 372 there is a pair of laterally extending fingers 312 and 314 on front head 320 (Fig.9). These can rotate in a plane perpendicular to the face of the paper. These fingers may be curved as shown in Figures 24, 25 and 26. The other end of the tool 372 is provided with fingers 313 and 315 which may be similar to fingers 312 and 314. As will be explained in the discussion of the tool 372, the arms support section 320 and 322 can be moved axially with respect to the support frame 301 of the tool 372. While manipulating, i.e. pushing or pulling the reach rod which is connected to nose piece 330, finger 312 can be aligned with valve SV1 and finger 314 can be aligned with valves SV8 and SV9. Likewise, the finger 313 on the other end of tool 372 can be aligned with valves SV4, SV2 and SV3. Finger 315 can be aligned with valves SV10, SV11 and SV12. Air under pressure (from conduits not shown) is applied to valves SV1 , SV8, SV9, SV4, SV2, SV3, SV10, SV11 and SV12. Thus when a minor shuttle valve is activated, pressurized air will flow into and through the conduit to which the valve is connected as indicated in Figure 7. These valves can be simple shuttle valves which permits this operation when activated by a finger. When fingers 312, etc. are removed from contact with the minor shuttle valve such as SV1 , pressure on the conduit such as 360 will be relieved. Such valves are well known. Larger shuttle valves V1 and V2 are provided. Shuttle valve V2 is a type valve that when air pressure is applied to one end it forces the internal arrangement of the valve to move in one direction to provide one flow path and when air under pressure is applied at the other end a second movement will be provided to provide a second flow path. The internal arrangement stays in a given position until pressure is applied to the end of the valve to cause internal movement.

That part of Figure 7 useful in setting a "hard " chuck or "soft" chuck between pads 32 and the interior of pipe 12 will now be discussed. Main" air on conduit 322 is provided to a port 330 in shuttle valve V2. One end of the shuttle valve V2 is connected by conduit 350 to minor shuttle valve SV10. The other end of valve V2 is connected to conduit 346 which is connected to minor shuttle SV3. Valve V2 has two outlet ports 328 and 326. Outlet port 328 is connected to a Y-shaped fitting 338 to divide into a first conduit 352 and a second conduit 354. The first conduit 352 is connected to a pressure control valve PCV1 whose outlet is connected to port 332 of major shuttle valve V1. This is set to have a lower pressure than the pressure coming in on line 354. Line 354 is connected to a second port 334 on valve V1 and is of a higher pressure. When SV8 is activated, air under high pressure flows through "hard chuck" set line 342 to the left end of shuttle valve V1. The internal arrangement of shuttle valve V2 now connects port 336 and inlet port 334. Outlet port 336 is connected through line

337 to inlet port 81 of piston setting cylinder 38. Thus a hard chuck is obtained between piston 112 and pad 32 with the interior of pipe 12. The other end of valve V1 is connected by conduit 344 to valve SV2.

Thus when valve SV8 is activated it moves the cylinder shuttle valve V1 to a position where the internal path to outlet port 336 is from inlet port 334 which is the high pressure air compared to that through port 332. The outlet port 336 is still connected through conduit 337 to inlet port 81 of the piston setting cylinder 38. When minor shuttle valve SV2 is activated air flows through line 344 to the right end of main shuttle valve V1. This shifts valve V1 to the left and connects outer port 336 with inlet port 332 which provides low pressure air to port 336 and conduit 337 to obtain a "soft chuck" on piston setting cylinder 38. When shuttle valve V2 is shifted to the right by applying air under pressure on conduit 350, pressurized air is applied through conduit 327 from port 326 to inlet port 80 in cylinder 38. Air pressure from cylinder 38 in contact with port 81 is relieved through conduit 337 which is connected either to ports 332 or 334, conduits 352 or 354 to shuttle valve V2 where it is vented internally by the shifting of the valve V2 to the left.

I shall now discuss that portion of the diagram of Figure 7 for use in providing air to ports 142 or 140 of piston setting cylinder 138. Air to port 140 is used to set the piston 178 with pads 180 against the interior of pipe 10. Flow of air through cylinder port 142 removes the pistons and pad 180 from contact with interior of the pipe. When valve SV4 is activated by hand (before pipe 12 is put on), pressured air is flowed through conduit 340 to the left end of valve V4 which pushes the valve to whereby the inlet air flows from port 368A through a path connecting port 368A with conduit 368 to port 140 to drive the piston 130 as shown in Figure 3 to set the piston pads to hold the left side of the spacing clamp in position. When valve V4 is shifted where conduit 368A is connected to conduit 370, air on conduit 368 is vented. Similarly, when inlet 368A is connected through valve V4 to conduit 370, air in conduit 368 is vented through shuttle valve V4. Shuttle valve V3 operates in a similar manner. When it is desired to retract the piston 178 with pad 180 from contact with the interior of pipe 10, valve SV11 is activated which drives the shuttle valve V4 so air goes from port 368A to the line 370 to port 142. Thus, activation of valve SV4 causes high pressure air to be transmitted through port 140 to set the pistons 178 with pads 180 and when it is desired to retract these, valve SV11 is activated and causes the high pressure air to flow through the port 142 and the high pressure air from port 140 is vented through a port in valve V4. The details of shuttle valves V1 , V2, V3 and V4 are not shown inasmuch as they are well known and such valves are commercially available to perform the functions required in the operations in regard to Figure 7.

I shall now discuss the part of that diagram of Figure 7 which is used to put a "soft" chuck on pistons 112 and pad 32. This includes activating small shuttle valve SV2 by proper manipulation of arm 313 as will be discussed later so that valve V1 is shifted so that the input port 332 is connected to the output port 336. The inlet port 332 is connected to PCV1 (pressure control valve) which has a lower pressure set than that on line 354. This low pressure air is conveyed through conduit 337 to port 81 of piston setting cylinder 38. When piston 112 is soft chucked against the second pipe 12 it is then time to activate the piston spacing cylinder 40 to move the pipe 10 and pipe 12 into contact with each other. This is accomplished by activating valve SV1 so that the major shuttle valve V3 connects the input power air to conduit 364 to inlet ports 74. This moves the two pipes into contact. Then pistons 112 and pad 32 are "hard" i.e. hard driven chucked against pipe 12. This is accomplished by activating valve SV9 by rotation of fingers 314. Activation of SV9 causes the pipe 12 to be moved away from pipe 10 to the point as illustrated in Figure 6. Activation of valve SV8 causes the piston 112 and pad 32 to be hard chucked. To move the pipes together to be in contact, SV1 is activated and to move the pipe 12 away from pipe 1 to get the desired clearance, valve SV9 is activated. At this point the piston 178 with pad 180 is hard chucked against pipe 10 and the piston 112 with pad 32 is hard chucked against pipe 12. The desired space has been obtained and welding may commence.

When the welding is finished the clamping tool must be removed. When reach rod 402 is pushed in and rotated to the left it activates valve SV10. This resets valve V2 to cause pressure to flow through line 327 to the atmosphere to release the front piston 112 and pads 32. Continue turning to valve SV11 causes the valve V4 to shift to the left, to have pressure on line 370 to port 142. This removes the pistons 178 and pad 180 from contact with the pipe 10. Now the spacing clamp is no longer "tied" to the pipe. Continued turning of the reach tool causes fingers 315 to contact valve SV12 which will have air pressure going to the right side of shuttle valve V5. This causes shuttle valve V5 to shift such that high pressure air from conduit 324 goes to motor 320 to start it and drive the spacing tool out of the pipe. When the clamping tool cleans the pipe, kill button

391 can be pushed to start the motor 320 in any well known manner.

I just described the structure and operation of an air control system which will control the setting of the spider ring pistons to the walls of pipes 10 and 12 and which will cause movement to obtain the ideal spacing for welding the two ends of pipe together. The system also explains how after the welding has been completed that the spacing clamp can be withdrawn.

Attention is next directed to that part of the drawings which illustrates the operation of the control tool and its relationship to the control valves shown in Figure 7. In this regard, attention is first directed to Figures 8 and 9. Shown in Figure 8 is a control tool 372 which has a front cylinder 306 and a rear cylinder

308 with a center member 301 therebetween. Front cylinder 306 is provided with a front head 320 which supports control fingers 312 and 314. Likewise, the rear head 321 is supported from rear cylinder 308. This rear cylinder 308 supports fingers 313 and 315. A connecting nose 330 is provided on the front head 320. The nose 330 has engaging pins 332 and 333 which are spaced 180 degrees apart. Engaging pins 332 and 333 are to lock into the coupling head of a reach rod as will be described later. As will also be described later the use of the head 320 can be pulled forward such that when they are rotated the Figures 312 and 314 are aligned with and contact valves SV1 , SV8 and SV9. Thus by proper axial movement and rotation of head 320 the valves SV2, SV8 and SV9 can be actuated. Likewise, by proper manipulation of the reach rod when it is connected to the connecting nose 330, the rear cylinder 308 can be moved backwards until the fingers 316 and 318 are over the valve SV4, SV2, SV3, SV10, SV11 and SV12. The shape of these fingers can be such SV8 and SV9 can be operated in sequence or simultaneous. Then rotation of the rear head 332 will actuate these valves. This applies to all such fingers.

Attention is next directed to Figure 9 in relation to Figure 8. Shown thereon is a central support frame 301 which is securely fixed to the bar 18 of the frame of the spacing tool as shown in Figures 1 , 2, 3 and 4. There is a larger hub 303 in approximately the center of the control of support frame 301. There is a smaller diameter cylindrical extension 302 to the front and a second smaller diameter cylindrical extension 304 to the rear of the central support frame 301. There is a key 352 fixed to hub 303 and fits into a slot 356 in the position of Figure 9. Slot 356 is shown more clearly in Figure 11 and is of about the same areal dimension as key 352 so that key 352 can be press fitted into the slot. There is a front angular space 358 and a rear angular space 354. When key 352 is in the position shown in Figure 9, the front head and rear head cannot rotate because the slot is rather narrow and just fits the key 55. However, when the tool is forced to the position shown in Figure 11 , key 352 is in angular space

354. This angular space goes all the way around the central body cylinder 350, thus the central body 350 can rotate with respect to the key 352. This is important for the operation of the tool for the intended purpose. When the device is pulled out so that the front head 320 is in the position shown in Figure 13, the front head can rotate with respect to the central support frame 301. Then fingers 312 will be aligned with valves SV1 , SV8 and SV9. When in this position of Figure 13, head 321 may rotate but fingers 313 and 315 will not contact valves SV4, SV2, SV3, SV10, SV11 and SV12 as the valves are not aligned with fingers 313 and 315. An examination of Figures 8 and 9 shows that the control tool is in a normal or free position. In this position neither front fingers 312 or 314 are aligned with any of the valves SV1 , SV8 or SV9. Likewise, neither of the fingers 316 and 318 aligned with any of the valves SV4, SV2, SV3, SV10, SV11 and SV12. Returning to Figure 9, particularly, spring 360 is held in the space inside front cylinder 306 by shoulder 362 which is connected to support frame 301. The other end of spring 360 is held in position by front head 320. Likewise, rear spring 364 is held in position about central body cylinder 350 within rear cylinder 308 by rear head 321 and shoulder 366 which is supported from central support frame 301. Central body cylinder 350 is rotatably supported within support frame

301 by bearings 368 and 370, respectively.

When it is desired to operate valves SV1 , SV8 and SV9 the coupling head 400 to the reach rod is maneuvered to the position shown in Figure 19. By pulling on reach rod 402 the coupling head 400 is placed in the position shown in Figure 19. Then by pulling on reach rod 402, the control tool 300 is moved to the position shown in Figure 13 whereby rotation of the head 320 the fingers 312 and 314 can contact the valves SV1 , SV8 and SV9 as illustrated in Figures 12 and 24. When this occurs, spring 364 becomes compressed. When operation of the valves SV1 and SV8 and SV9 is completed, the reach rod is relaxed or pushed or rotated to the position shown in Figure 23 where it can push the head

320 and the control body cylinder 350 to the position shown in Figure 11. In this position fingers 313 is aligned with valves SV2 and SV3 and finger 315 is aligned with valve SV10 and SV11 and SV12 all as illustrated in Figure 10. When the coupling head 320 is in the position shown in Figure 23, rotation of reach rod 402 rotates central body cylinder 350, rear head 321 and rear fingers

313 and 315. Nut 319 is secured to a bolt which has a base shaft 317 which extends into and is secured to front head 320. As shown in Figures 24, 25 and 26, the shaft is not round but has straight sides so that it will rotate with head. Thus central body cylinder 350 rotates with front head 320. The same arrangement is made with rear head 321.

As illustrated in Figures 24, 25 and 26, rotation of the central body cylinder 350 rotates the front head 320 and fingers 313 and 314. In Figure 24, there has been no rotation of the head 320 from the neutral position. In Figure 25 the front head 320 has been rotated to the right or clockwise to activate valve SV1. In Figure 26 the coupling head 320 has been rotated to the left or counterclockwise to activate valve SV9 and SV8. Similar operation would be obtained by the rotation of rear head 321 and fingers 313 and 315 when they are aligned with the respective valves as illustrates in Figure 10. As shown in Figure 9, nose cone 330 extends outwardly from nut 319 from front head 320. This nose cone 330 has locking pins 332 and 333 and a cone shaped front 337 which guides the cone 330 into the coupling head 400 on the end of the reach rod 402. Attention is now especially directed to Figures 14, 15 and 16. Shown thereon is an entry cavity 408 as shown in Figure 16 in large cavity 418 which in cross-section has a circular portion 417 and two slot-like members 408 and 410 which will receive the pins 333 and 332 which extend out beyond the circular portion 417. There is an enlarged circular like cavity 404. As shown in Figure 16 it is slightly larger in diameter than the diameter from the exterior of slot 408 and 410. There is a slot 406 in the walls of the coupling head 400 and it extends through the head as shown in Figure 16. As shown in Figure

15, in this view the slot 406 is shown as being on either side of the enlarged internal diameter portion 404. The purpose of this elongated slot 406 is to permit the pins 332 and 333 to move longitudinally from the position shown in Figure 19 to the position shown in Figure 23. When these pins 333 are in the position shown in Figure 19, they abut against shoulder 412 of the coupling head. When in the position shown in Figure 21 , the pins 332 and 333 are moving toward the position shown in Figure 23 wherein the pins abut against shoulder 414 on the outer end of the slot 406.

Attention will now be directed toward the entry of the connector pin 230 and to the coupling head 400 and the maneuverability of it to obtain the different positions. Figure 17 shows the connector pin 330 in position to enter the coupling head 400. It is seen that the pins 333 and 332 are aligned with the control pin receiving slots 408 and 410 in the coupling head 400. The coupling head is pushed over the connector pin 330 until it reaches the position shown in Figure 18. At that time, the control pins 332 and 333 are within the enlarged portion 404 of the coupling head 400.

If it is desired to pull on the reach rod 402 and on pins 332 and 333 to bring the tool into the position shown in Figure 13, the reach rod rotates until the pins 332 and 333 are aligned with slot 406. Then the reach rod is pulled until the pins are in the position shown in Figure 19 and 20. Now pulling on the reach rod 402 the pins 302 and 333 abut shoulder 412 and pulling on the reach rod will cause the tool to reach the position shown in Figure 13. Now rotation of the reach rod will cause the fingers 312 and 314 to contact the valves as illustrated in Figure 12.

When it is desired to push on the tool to obtain the position shown in Figure 11 , one merely pushes on the reach rod 402 where the pins 332 and 333 go through the position shown in Figure 21 to that shown in 23. At this time the pins 332 and 333 are abutted against shoulder 414 of the coupling head 400. Then pushing on the reach rod will cause the control tool to obtain the position shown in Figure 11. At this time, rotation of the reach tool 402 turns the coupling head 400 and the walls of the slot 406 causes the control pin 330 to rotate the control body cylinder 350 and the rear head 312 to be in the position shown in Figure 13 where spring 354 is compressed and the fingers 313 and 315 are in the position shown in Figure 10. Thus, rotation of the central cylindrical shaft

350 rotates head 312. Counterclockwise rotation are to the left cause pin finger 315 to operate valves SV10, SV11 and SV12. Clockwise rotation or turning the reach rod to the right causes finger 313 to operate valves SV2, SV3 and SV4. Fingers 313, 315 and 312, 314 are curved as necessary to contact their associated valves in the proper sequence.

As explained in the discussion considering Figure 7, these rotations of the fingers to contact various valves causes the operation as described to function in the manner required in the discussion of Figure 7.

Attention is next directed to Figures 27 and 28. These illustrate a modified control tool for operating air valve to control sequence of operations and may be a substitute for that tool shown in Figures 8, 9, 10, 11 , 12, 13. In Figure 27 there is a cylindrical hub or frame 301 A. This hub is held in place to the frame of the spacing tool by bars 18A. Hub 301 A is a hollow cylindrical member having a rear shoulder 430 and a front shoulder 432. A positioning rod 402 has about the same, but slightly less than, the diameter of the bore in hub 301 A and extends into a finger holding body 412 to which it is secured. A spring 400 is mounted about positioning rod 402 and is held in position between the rear shoulder 430 of frame 301 A and the right end or shoulder 434 of body 412. Mounted on body 412 are fingers 312A and 314A. These fingers operate like the fingers 312 and 314 and 313 and 315 of Figure 8. However, in this embodiment of the control tool, fingers 313 and 315 are not needed. Valves SV1 , SV8 and SV9 are aligned in Group I similarly as those on the right end of Figure 8 and Valve SV4, SV2, SV3, SV10, SV11 and SV12 are aligned as Group II similarly as those on the left end of Figure 8 except that the two groups of valves can be closely spaced inasmuch as only one set of fingers 312A and 314A are needed. An "H" shaped slot is cut in the wall of frame 301 A and extends from the outside through to the interior cavity. This "H" slot includes central slot 416 which is aligned with the longitudinal axis of positioning rod 402. There are double end slots. There is a slot perpendicular to central slot 416 which has slot sections 418 and 422. On the front end of central slot 416 is a perpendicular slot comprising slot sections 420 and 424. A positioning pin 222 is secured to positioning rod 402 and extends up into this "H" slot and can be manipulated to be in any position therein. Pin 222 may be secured with a threaded hole in rod 402.

When one wishes to operate any one or more of valves SV2, SV3, SV10, SV11 or SV12 the positioning pin 404 is pushed or pulled into the position shown in Figure 27. When in this position the arms 312A and 314A are in a position to operate the valve just listed. Operation of these valves by these fingers would be similar to that operation described above in relation to that shown in Figure 10.

When it is desired to have valves SV1 , SV8 and SV11 to be aligned with control fingers such as indicated in Figure 12 the tool of Figure 27 is moved into the position shown in Figure 28. This is easily accomplished by connecting a reach rod with a special connecting head as shown in Figures 17 through 23. The same coupling head and connector pin shown in those figures can be used with this tool of Figures 27 and 28. Then the connecting nose 330A of Figures 27 and 28 would function the same as in relation to coupling head 400 of the reach rod 402 as does connector pin 330 of Figure 17 for example.

When changing the control tool from the position shown in Figure 27 to the position of Figure 28, the positioning rod 402 is simply pulled through hub 301A to the position shown in Figure 28. There positioning pin 402 is against the front end of slots 420 and 424. By rotating reach rod the positioning pin 402 can rotate in the slots 420 and 424 so that the fingers 312A and 314A can operate the valves SV1 , SV8 and SV9 in a manner similar to that above in regard to Figure 12, i.e. rotating body 412. Body 412 is secured to positioning rod 402. Thus, manipulation of the reach rod would be the same as it was in connection with the tool of Figure 9 for example. When it is desired to actuate the valves in the left hand column SV2 to SV11 one would align positioning pin 402 with the center slot 417. Then the reach rod can push on head 330A and that together with the spring 400 would drive the tool to the position shown in Figure 27. Then by rotating the reach rod it will turn positioning rod 402 so that fingers 312A and 314A can be manipulated to perform the desired functions.

Air under sufficient pressure to perform the functions described herein is supplied to minor shuttle valves SV1 , SV8, SV9, SV4, SV2, SV3, SV10, SV11 and SV12 from a source not shown.

Thus, it is apparent that there has been provided, in accordance with the invention, a spacer clamp improvement that fully satisfies the objects, aims and advantages set forth above. While the invention has been described in conjunction with specific embodiments thereof, it is evident that many alternatives, modifications and variations will be apparent to those skilled in the art and in light of the foregoing description. Accordingly, it is intended to embrace all such alternatives, modifications and variations as fall within the spirit of the appended claims.

Claims

WHAT IS CLAIMED IS: 1. A spacer clamp for use in welding one end of a pipe to an end of a second pipe which comprises: a frame; a first spider ring supported from said frame and having a plurality of radial holes; a second spider ring supported from said frame and having a plurality of radial holes; a piston in each hole in each said spider ring for radial movement, each piston having an inner end and an outer end; a first power piston for driving each said piston in said first spider ring either in or out of its hole; a second power piston supported from said frame for driving each said piston in said second spider ring in and out; a spacing power piston supported from said frame for moving said second spider ring toward or away from said first spider ring.

2. A spacer clamp as defined in claim 1 including a stop supported by said frame for limiting the movement of the piston of said spacing power piston.

3. A spacer clamp improvement for clamping the end of two joints of pipe which are to be welded to obtain a desired spacing between the two ends which comprises: a support disk-like plate having a first side and a second side; a support shaft fixed to and extending to either side of said support plates and perpendicular thereto; a first spider ring fixed to and supported on a first side of said support plate, said spider ring having a plurality of radial holes therethrough; a spider ring piston with pad at one end thereof and extending through said radial hole in said first spider ring; a first power cylinder having a first cylindrical housing and two spaced apart ports in the housing; a cup-like cover member connecting said first housing to said spider ring; a first piston within said first power cylindrical and spaced for movement between said first and second port and having a piston rod extending through said cup-like spacer connected housing; a first piston rod connected to said first piston; a hub within said cup and connected to said first piston rod; a link connecting said hub to said spider ring piston such that movement of said hub causes the piston to move inwardly or outwardly in said hole in said first spider ring; said first piston rod being adapted to receive and slide over one end of said shaft; a second spider ring supported from said support plate in a manner to have limited axial movement therewith; a second cylindrical housing having a second piston therein said piston having a piston rod supported from and surrounding said shaft on the other side of said support plate, and having a first port and a second port with the second piston mounted therebetween; a hub supported at the inner end of said second piston rod; a second linkage connecting said hub with said pistons of said second spider ring such that axial movement of said hub moves the piston in and out a hole in said second spider ring; a second cup-like cover connecting said second housing to said second spider ring; said second piston rod extending through a hole in the middle of said cover a pipe spacing piston housing connected to the second cylindrical housing; a spacing piston mounted within said pipe spacing piston housing and secured to said shaft; a first port and a second port within said pipe spacing piston housing in which one port is on one side of said pipe spacing piston and the other on the other side; the pipe spacing piston housing, the second cylinder housing and the cup like cover connected in tandem to said second spider ring such that movement of said power spacing housing causes movement of the second spider ring.

4. A spacing clamp improvement as defined in claim 3 in which the limiting mechanism includes a threaded bolt extending through holes in said first spider ring, said support plate and said second spider ring, and also includes a calibrated collar on the end of said bolt extending through said second spider ring, and a spacer movement limiting nut on the other end of the bolt thereof.

5. A system of controlling pressurized fluid to a pipe spacing clamp having a first power cylinder with a first port and a second port, a second power cylinder having a third port and a fourth port and a spacing power cylinder having a fifth port and a sixth port which comprises: a shuttle valve V^ having an inlet ports 7 and 8 and an outlet port 9, a first end port A and a second end port B, pressured fluid on end port A causes the valve to shift so that inlet port 7 is in communication with outlet port 9 and when inlet port B is applied with pressure inlet port 8 is in communication with outlet port 9; a second shuttle valve V₂ having inlet port 10 and outlet ports 11 and 12, end port C and end port D on opposite ends thereof such that when pressure is applied to port C the valve shifts so that inlet port 10 is in fluid communication to port 12 and when pressure is applied on end port D the valve shifts internally so that inlet port 10 is in fluid communication with outlet port 11 ; a shuttle valve V₃ having an inlet port 13, two outlet ports 14 and 15, a first end port E and a second end port F such that when pressure is applied on end port E inlet port 13 is in fluid communication with the outlet port 14 and when fluid pressure is applied on end port F inlet port 13 is in fluid communication with outlet port 15; a shuttle valve V₄ having an inlet port 16 for pressurized fluid, an outlet port 17, another outlet port 18 such that when pressure is applied on ports G inlet port 16 is in fluid communication with outlet port 17 and when fluid pressure is provided on end port H inlet port 16 is in fluid communication with outlet port 18; a pressure control valve; a fluid stream divider connected to port 12 of valve V₂ and having a first fluid conduit and a first conduit connected to said pressure control valve and the second conduit is connected to port 8 in said valve V.,; a low pressure conduit connected between said pressure control valve and to port 7 in valve V^ a pressure source connected to inlet port 10 of valve V₂ ; a pressure source connected to port 13 of valve V₃; a pressure source connected to port 16 of valve V₄; a third conduit connecting port 9 of valve \f^ to port 3 of the second power cylinder; a fourth conduit connecting port 11 of valve V₂ with the port 4 of the second power cylinder; a fifth conduit connecting port 17 of shuttle valve V₄ to port 1 of the first power cylinder; a sixth conduit connecting outlet port 18 of shuttle valve V₄ to port 2 of the first power cylinder; a conduit 7 connecting outlet port 14 of shuttle valve V₃ with said port 6 of the pipe spacing power cylinder; a conduit 8 connecting the outlet port 15 of valve V₃ with port 5 of the pipe spacing power cylinder; first means to apply fluid under pressure selectively to port A and port B of valve V.,; second control means to selectively apply pressurized fluids to port C and port D of valve V₂; third control means to selectively apply fluid under pressure to port E and F of valve V₃; fourth control means to selectively apply control fluid to port G and/or H of valve V₄.

6. A device useful for actuating valves to control power cylinders in an internal pipe clamp which comprises: a central cylindrical body; a rear head on one end of said cylindrical body; a front head attached to the other end of said central cylindrical body; a central hollow support mandrel having a bore with the midsection of the bore approximately the same diameter as that of the central cylindrical body, and having a rear and a front extension cylindrical member, each having an external diameter approximately the diameter of the interior of the rear front cylinder and an internal diameter larger than the diameter of said central cylindrical body; a key; the central portion of said central support mandrel being provided with a key slot extending between the front and rear extension cylindrical members and in which said key may slip longitudinal; a corresponding slot on the central cylindrical body said slot being at about the midpoint thereof into which said key is secured; a first spring in said rear extension and a second spring in said front extension and held respectively between the rear head and the center support frame and the second spring being held between the front head and the central support frame; an activating pin in at least one of the heads; a connector pin extending longitudinally outwardly from said front head and having at least two circumferentially spaced apart holding pins.

7. A device as defined in claim 6 including a coupling head for use with said connector pin which comprises: a cylindrical body having a front end which is substantially planar and a second end which is connect able to said reach rod; said body having a longitudinal axis and containing a cylindrical bore extending part way into said body with a mouth at the face of the bore; a lateral slot extending through the walls of said body, all of said slot being spaced from said face, a circular like cavity of a diameter slightly greater than the distance between the tops of actuating pins 332 and 333 and cut into the walls of said bore and spaced from said front end, a pair of spaced apart entry slots in the main cavity of the size sufficient to receive two connector pins, in the wall of said body, entry slot is spaced about ninety degrees circumferentially from the first slot.

8. A coupling head which comprises: a cylindrical body having a front end which is substantially planar and a second end which is connect able to said reach rod; said body having a longitudinal axis and containing a cylindrical bore extending part way into said body with a mouth at the face of the bore; a lateral slot extending through the walls of said body, all of said slot being spaced from said face, a circular like cavity of a diameter slightly greater than the distance between the tops of actuating pins 332 and 333 and cut into the walls of said bore and spaced from said front end, a pair of spaced apart entry slots in the main cavity of the size sufficient to receive two connector pins, in the wall of said body, entry slot is spaced about ninety degrees circumferentially from the first slot.

9. A device useful for actuating valves to control power cylinders in an internal pipe clamp with frame which comprises: a hollow central hub with a rear shoulder and having a cylindrical opening therethrough and adapted to be fixed to the clamp frame, said hub having an "H"-slot system extending through the wall of the hub with the cross of the "H" being a central slot parallel to the longitudinal axis of the hub and an end slot at the each end of the central slot and which are perpendicular to each other; a positioning rod slidably extending through the hub and having a positioning pin secured thereto and extending into the H-slot; a body secured to said positioning rod at one end thereof; a first finger supported by said body; and a spring positioned between said body and said rear shoulder of said hub and surrounding said positioning rod; a connecting nose on the end of said positioning rod extending out the end opposite the body.

10. A device as defined in claim 9 including a shoulder on said positioning rod between said connecting nose and said body.

11. A spacer clamp as defined in claim 1 which includes a stop mechanism comprising a bolt at least partially threaded and extending through holes in said first spider ring, and said second spider ring, and also includes a calibrated collar on the end of said bolt which extends out from said second spider ring and a spacer limiting nut on the end of the bolt.

12. A system as defined in claim 5 in which: said first means includes minor shuttle valves SV2 and SV1 ; said second control means includes minor shuttle valve SV3 and SV10; said third control means includes a minor shuttle valve SV9 and a minor shuttle valve SV1 ; said fourth control means includes minor shuttle valve SV11 and minor shuttle valve SV4; and finger means to selectively activate said minor shuttle valves SV1 , SV2, SV3, SV4, SV9, SV10, SV11.