US3602031A

US3602031A - Internal pipe radius control

Info

Publication number: US3602031A
Application number: US859314A
Authority: US
Inventors: Dan H Graff
Original assignee: Individual
Current assignee: Individual
Priority date: 1969-09-19
Filing date: 1969-09-19
Publication date: 1971-08-31
Anticipated expiration: 1988-08-31

Abstract

A self-powered internal pipe radius control having suitable external control means includes a pair of powered wheels for propelling the radius control device internally through pipe sections. In one embodiment the power to propel the device and to operate the various components is supplied from a self-contained air tank which can be pressured before insertion of the device in a pipe section, or, if desired, may be repressured by suitable air connections during operation of the device. A guiding framework supports the powered wheels and tensionable guide wheels and provides support for the air tank and for radially extendable shoe members which can be driven by suitable air motors to contact the interior surface of a pipe section to effect the proper radius control. Two similar sets of shoe members are provided on the framework. Each set is individually controlled by its own air motor. Each motor drives rotatably a circumferential chain member which in turn rotates a sprocket operating an eccentric member which bears against an internal radius of a shoe member to move the shoe member radially of the device. Each eccentric operates against a shoe member which is rotatably positioned on a shaft adjacent to the shaft on which the eccentric moves. Another embodiment of the radius control is powered by self-contained electric motors, which may be furnished electric power by batteries.

Description

Dan 11. Graft General Delivery, Coweta, Okla. 74429 [211 App]. No. 859,314

[22] Filed Sept. 19, 1969 [45] Patented Aug. 31, 1971 [72 Inventor [54] INTERNAL PIPE RADIUS CONTROL 10 Claims, 13 Drawing Figs.

[52] U.S. Cl. 72/393,

72/120, 72/399, 29/200 JP [51] lnt.Cl. B21d 41/02 [50] Field 01 Search 72/393,

399, 112, 1 l3, 1 17, 118, 120, 122; 29/464, 493, 523, 524, 200 R, 200 P, 244, 272

Pollard 72/ l 20 by batteries.

Primary Examiner-Charles W. Lanham Assistant Examiner-Michael .1. Keenan Attorney-Robert E. Massa ABSTRACT: A self-powered internal pipe radius control having suitable external control means includes a pair of powered wheels for propelling the radius control device internally through pipe sections. In one embodiment the power to propel the device and to operate the various components is supplied from a self-contained air tank which can be pressured before insertion of the device in a pipe section, or, if desired, may be repressured by suitable air connections during operation of the device. A guiding framework supports the powered wheels and tensionable guide wheels and provides support for the air tank and for radially extendable shoe members which can be driven by suitable air motors to contact the interior surface of a pipe section to effect the proper radius control. Two similar sets of shoe members are provided on the framework. Each set is individually controlled by its own air motor. Each motor drives rotatably a circumferential chain member which in turn rotates a sprocket operating an eccentric member which bears against an internal radius of a shoe member to move the shoe member radially of the device. Each eccentric operates against a shoe member which is rotatably positioned on a shaft adjacent to the shaft on which the eccentric moves. Another embodiment of the radius control is powered by self-contained electric motors, which may be furnished electric power PATENTED AUG31 l9?! 3.602.031 sum1nr7 INVENTOR. DAN H. GRAFF A T TORNE Y mama) was i 1971 sum 2 BF 7 R 0 m E V m DAN H. GRAFF ATTORNY PATENTEU AUG31 |97i SHEET 3 BF 7 v ATTORNEY PATENTED M183] 1971 SHEET 0F 7 'IHI mm 9: Wm

INVENTOR. DAN H. GRAFF A TTORNE Y PATENTED AUGBI IHTI 3502,,0-31

SHEET 5 BF 7 INVENTOR. DAN H GRAFF A TTORNE Y PATENTEB M1831 an 3,602,031 sum 5 OF 7 INVENTOR. DAN H. GRAFF ATTORNEY PATENT EU A1183] m:

SHEU 7 BF 7 INVENTOR DAN H. GRAFF A T TORNE Y INTERNAL IPIIPIE RADIUS CONTROL BACKGROUND OF THE INVENTION This invention relates to radius control devices, and more particularly to radius control devices useful for reforming the radius of a pipe to substantially circular geometry. Still more particularly, this invention relates to radius control devices for reforming pipe sections to substantially circular geometry and for holding the pipe sections in this conformation for sub sequent operations. Still more particularly, this invention relates to radius control devices useful for reforming and holding terminal portions of adjacent pipe sections in substantially circular geometry and for holding the adjacent pipe sections in proper alignment for subsequent operations, such as welding the adjacent ends together.

Quite commonly, certain portions of a pipe section or similar cylindrical object will become slightly out of round and means must be provided to reform the pipe section into the prescribed circular conformation. For example, in aligning two adjacent pipe sections so that they may be welded together, quite frequently the ends of the pipe sections are slightly out of round, and will not fit together properly for welding. Therefore, some means must be found to bring the adjacent radii into the same geometrical conformation. Presently, this is accomplished by employment of various kinds of internal or external pipe lineup clamps. An internal pipe lineup clamp is positioned inside a pipe section near the end thereof so that another pipe section may be brought into juxtaposition, and by proper manipulation, components of the clamp are expanded against the inner surface of the ends of the adjacent pipe sections so that the radii are brought into the same conformation. An external pipe lineup clamp is employed around the external surface of adjacent pipe sections and is powered by various means to squeeze the adjacent ends of pipe into the same conformation. Both types of clamps usually are employed to continue holding the pipe sections in the proper conformation while they are being welded, at least through the first pass. I

Several types of internal pipe lineup clamps are described in the following US Pat. No. 2,830,551 to Miller, issued Apr. 15, 1958; No. 3,031,994 to Clark, issued'May I, 1964; and No. 3,044,431 to Cummings, issued July 17, 1962.

One important advantage of the internal radius control of this invention is that the extendable shoe members are designed to contact a significant portion of the internal surface of the pipe section and have a contacting surface which has a radius of curvature substantially commensurate with the radius of curvature of the pipe section with which the device is employed. That is, in an extended position the shoe members contact a substantial area of the internal pipe surface. Thus, radial pressure is applied to a significant portion of the pipe and a truer circular conformation of the pipe section is achieved. In some internal pipe lineup clamps, the contacting member of the clamp comprises the end of a rodlilte member or is a member contacting the internal surface of the pipe in only a very limited area. Then, when the adjacent pipe sections are aligned and welded, the cross section of the welded area is not a true circle but is somewhat polygonal, and when the clamp pressure is released the pipesections attempt to assume their original condition and occasionally the weld cracks. But, with the radius control of this invention the pipe sections are welded when the ends thereof are substantially circular and any force resulting from an attempt of the pipe sections to assume their original conformation is rather evenly distributed around the circumference of the weld and cracking is minimized.

The shoe member of this radius control are operated against by eccentric members which contact and move along an inner surface of the shoe members having a radius also comparable to the radius of curvature of the pipe section with which the radius control is employed. This is described as a "power curve and is described in detail hereinafter, but is particularly important since the eccentric members are permitted to operate against this surface with a smoothly increasing pressure'to extend the shoe members. Thus, the shoe members are extended to contact and bear against a maximum area of the pipe section.

The primary object of this invention is to provide an internal pipe radius control which is simple in construction, sturdy, efficient in operation, and easy to operate.

Another object of this invention is to provide an internal pipe radius control which is self-powered and which may be easily controlled from a remote position.

Another object of this invention is to provide an internal pipe radius control which can be used to place adjacent ends of pipe sections in proper alignment for welding or other operations.

Another object of this invention is to provide an internal pipe radius control which will maintain a radius of a pipe section in substantial circular conformation subsequent to further treatment of the pipe section.

Still another object of this invention :is to provide an internal pipe radius control which can be easily and efficiently located in position adjacent an end of a pipe and which can then selectively secure a second pipe section in juxtaposition thereto and which can selectively release either or. both of said pipe sections.

BRIEF DESCRIPTION OF THE DRAWINGS Further objects and advantages of the invention will become apparent from the following description and claims, and from the accompanying drawings, wherein:

FIG. 1 is a perspective view of an internal pipe radius control according to this invention.

FIG. 2 is a cross-sectional view along the lines 2-2 of FIG. 1.

FIG. 3 is a cross-sectional view along the lines 3--3 of FIG. 11.

FIG. 4 is a cross-sectional view along the lines 4-4 of FIG. 11.

FIG. 5 is a cross-sectional view along the lines 5-5 of FIG. 1.

FIG. 6 is a fragmentary cross-sectional view of pipe engaging members of this invention and other operating components.

FIG. 7 is a fragmentary front elevational view of a powered wheel mechanism of this invention.

FIG. 8 is a cross-sectional view along the lines 8-fi of FIG. 7.

FIG. 9 is a fragmentary side elevational view of control components of this invention.

FIG. 10 is a cross-sectional view along the lines 10-10 of FIG. Q.

FIG. 111 is a side elevational view of a control rod according to this invention.

FIG. 12 is a side elevational view of another embodiment of this invention, describing an electric powered internal pipe radius control.

DESCRIPTION OF THE PREFERRED EMBODIMENTS An internal pipe radius control according to this invention comprises a plurality of radially extendible shoe members arranged circumferentially on a framework. body with a plurality of eccentric members disposed on the body inwardly adjacent the shoe members, an eccentric member and a shoe member pivotally attached to the body on the same pivotal member, each eccentric member positioned to urge outwardly a shoe member positioned on an adjacent one of the said pivotal members, and operating components to drive the eccentric members rotatably.

The internal pipe radius control of this invention incorporates all of the operating components on a framework, and in operation, the device is inserted into one end of a pipe section and a long control rod is either attached to the radius control device prior to the insertion of the device into the pipe section or inserted into the opposite end of the pipe section and connected to the radius control device when the device is positioned for insertion into the pipe section. The control rod is of sufficient length to extend beyond the opposite end of the pipe section so that the handle of the control rod can be manipulated properly to actuate control buttons on the radius control device. Forward pulling of the control rod causes the actuation of certain control buttons to further actuate valves operating the powered wheels so that the device can move into and through the pipe section under its own power, either forwardly or backwardly. Rotation of the control rod will cause actuation of certain other control buttons which further actuate other valves permitting extension or retraction of the pipe-engaging shoe members as desired.

An air tank is included on the body framework, and can be pressurized with compressed air prior to insertion of the radius control into a pipe section so that the radius control will be capable of operating under its own power with only the control components being operable externally.

In a second embodiment of the radius control, the power means is by electric motors and suitable electric storage batteries can be included in the body framework to make the radius control self-powered with only the control means being operable externally.

In addition to the usage of the radius control of this invention for causing adjacent pipe section ends to assume similar circular conformation and to be held in position for welding, it is contemplated that the radius control of this invention is usable for other purposes, as for example, for pipe bending operations. In pipe bending operations one of the difficulties is the occasional collapsing of a portion of the pipe. However, to prevent this collapsing, two of the radius control devices of this invention can be employed, with one to be placed in the pipe on each side of the section where the bend is to be accomplished. Thus, with the radius control devices maintaining the pipe in substantially circular conformation, the bend can be completed without collapsing the pipe.

Referring now to the drawings in detail, in FIG. 1 a radius control, 10, generally, according to this invention is described, and includes a body portion comprised of a plurality of guiding members 12, attached to a nose plate 13, a plurality of central frame members 14, and an air tank, 16, all of which cooperate to form proper support means for the various operating components of the radius control. Secured in position between guiding members 12 and central frame members 14 are a pair of plate members 18 and a spacer member 20, all held in position by a suitable machine bolt 22 and nut 24. Machine bolt 22 also acts as an axle upon which sprocket 26, eccentric 28, and shoe member 30 (FIGS. 2 to 6) freely rotate in a manner hereinafter described, with sprocket 26 and eccentric 28 secured to each other in a suitable manner as by welding or by pinning. Shoe member 30 becomes positionable against the internal surface of a pipe section 31. A carrying member 32 is pivotally attached to the body of the radius control at a suitable position as by attachment to the rearmost plate member 18, and is useful in lifting and carrying the radius control by a crane or other lifting device as desired.

As mentioned above, the radius control of this invention is self powered, and the manner of this locomotion is clearly described in FIGS! 1, 7, and 8. In FIG. 7, a pair of idler wheels 34, are shown positioned on a machine bolt 36 passing through suitable openings in brackets 38 and secured by machine nut 40. Brackets 38 are secured to support frame 42. A central powered wheel 44 is positioned rotatably on shaft 46 which passes through openings in brackets 48 and is held in position by properly threaded machine bolt 50 which has secured to its other end sprocket 52 fitted with chain 54 which also passes around and receives power from sprocket 56 on shaft 58 of air motor 60. Air motor 60 has

air connections

62 and 64 connected by

air lines

66 and 68 to a source of compressed air as can be supplied from air tank 16, by proper manipulation of air controls as further described hereinafter.

Proper tensionable positioning of the radius control within a pipe section is accomplished by operation of tensionably adjustable wheel 70 mounted on axle 72 which passes through an opening in brackets 74 and 76 and which is threaded to receive a suitable machine nut 78. Bracket 76 is pivotally attached to frame members 14 by means of machine bolt 79 which is threaded to receive nut 80. Bracket 76 is brought into suitable tensionable adjustment by operation of springs 81A and 81B positioned on extension 82 which passes through bracket 83. Extension 82 82 is suitably threaded to receive machine nuts 84A and 848 with machine nut 848 secured to bracket 76. Washers 85A, 85B, 85C, and 85D, are in position on extension 82 in order to give proper alignment to springs 81A and 818. Then, a desired tension can be given to springs 81A and 818 by suitable positioning of extension 82 in machine nuts 84A and 84B. A pair of nontensionable wheels 86 are spaced around air tank 16. Wheel 86 is rotatable on axle 87 which passes through bracket 88 and which is suitably threaded to receive machine nut 89.

The radius control components of this invention are described most clearly in FIGS. 2 to 6 as described briefly above. An internal chain 90 and a circumferential chain 92 are secured to rotary plate 94 by means of

machine bolts

96 and 98 respectively passing through

respective openings

100 and 102 in

lugs

104 and 106. Rotary plates 94 are positioned rotatably on a tubular shaft member 108 which is arranged to provide for the passage therethrough of air conduits or other control media from one end of the radius control to the other. Tubular shaft member 108 also provides means for the attachment thereto of springs 110 which have one hook end 112 passing through a lug 114 and a second hook end 116 passing through an opening 118 in shoe member 30, which springs bias shoe member 30 toward tubular shaft 108. Then, as shoe members 30 are moved radially outwardly by operation of eccentrics 28, springs 110 are brought into increased tension, and as eccentrics 28 continue in their rotative movement, shoe members 30 move radially inwardly away from the surface of pipe section 31 by the tension of springs 110. Eccentrics 28 are given their rotative movement by the cooperation of sprocket teeth 120 with chain 92. Chain 92 is moved rota- .tively with rotary plate 94 by the cooperation of sprocket teeth 122 on sprocket 124 with chain 90. Sprocket 124 is positioned on shaft 126 which is a drive shaft of transmission assembly 128. Transmission assembly 128 is a conventional assembly employed to provide for suitable speed reduction from air motors 130 with which transmission 128 is connected through chain linkage 132 linking sprocket 134 on shaft 136 with sprocket 138 on shaft 140. Transmission assembly 128 and air motor 130 are secured to brace member 142 by any suitable means, such as bracket 144 holding air motor 130 in position. Air motors 130 have air connections as best shown in the schematic diagram of FIG. 13 for connection with the control components and air tank 16 for operation of the expandible members. The, manner in which the control members operate is described hereinafter. A cover plate 146 is secured toplate member 18 to protect the chain members from damage and to reduce the danger to persons operating the radius control. To limit the rotative movement of shaft 126 on transmission assembly 128 a stop lever 148 is positioned on shaft 126 and as shaft 126 rotates, stop lever 148 contacts a suitable bracket (not shown) situated on the frame of the radius control at the desired arcuate movement of the shaft 126 to prevent damage to the pipe sections being operated against or to the operating components of this radius control. Conventional pressure release valve is incorporated into the pressure regulating apparatus of this device to provide relief for the pressure built up by the forceful movement of the stop lever 148 against the limit control brackets which it contacts. The rotative movement of shaft 126 is limited in either direction by contact of lever 148 with the limit control brackets. That is, the movement of the expansion members of the radius control can be limited in either their radially extendible direction or their retractable direction, and thus they can be protected from damage.

FIGS. 1, 9, 10, 12, and 13 describe the mechanical control components of the radius control. In FIG. 12 a control rod 150, generally, is described, and is seen to include a control rod handle 152, which an operator holds an manipulates, a tubular section 154, which is hollow in order to serve as an air duct; a brace portion 156, generally, which includes extension member 158 and circular member 160; an air tube extension 162 on which is secured a conventional air hose connection 164; a hook member 166; and a spring loaded latch'168 which is received slidably in eyes 170 and is biased to a closed condition by spring 172. Hook 166 is connected through eye 174 with latch 168 biased closed accordingly, thereby holding hook 166 in position. Then, with control rod 150 thus connected with the radius control, brace portion 156 is positionable against the front portions of the guiding members 12 so that the operator can have better control over the device. When the operator exerts a pulling motion on the control rod, he will also cause a forward tension on receiving eye 174 and other components of the radius control connected therewith. When the operator rotates the control rod handle 152, he will thus cause rotative motion of the receiving eye 174 and the other components connected with that member.

For pressurizing air tank 16, air hose connection 164 may be connected to a suitable air valve 178 (FIG. 12) at the end of air line 180 communicating with air tank 16. Then, after the air tank 16 is pressurized, the radius control is capable of being operated under its own power. It is perceived that control rod 150 does not have to include air connections to pressurize the air tank, and that the air tank could be pressurized by independent air connections before the radius control is inserted into the pipe section.

Referring now specifically to FIG. 9, the receiving eye 174 is secured to a shaft 182 which is positioned slidably through member 184 and nose plate 13. Member 184 extends through nose plate 13 and includes a slot 186 in position to receive pin 188 at the proper angular position of shaft 182 and is connected with flange 190 which has positioned thereon yoke 192. Shaft 182 is biased toward the rear of the radius control by the tension of spring 194 which bears between flange 190 and circular member 196. Member 196 is held in place by a pair of

machine nuts

198 and 200 threadable on proper threads ofshaft 182.

Then, in one mode of operation, a pull on receiving eye 174 causes shaft 182 to move forwardly against the tension of spring 194 so that member 196 is brought into contact with valve button 202. The depressing of valve button 202 opens valve 204 and brings air line 66 into communication with air line 206 so that air motor 60 is actuated in a condition to drive the power wheel 34 in forward rotation so that the radius control moves forwardly through the pipe section. Then, as the radius control emerges from the pipe section, a person standing adjacent the end of the pipe section presses valve button 208 which opens valve 210 in line 68, bringing about communication between line 68 and air line 212 connected with air line 206 to T-connection 214 with reserve air tank 216. Air flowing through line 212 into air motor 60 would normally cause air motor 60 to rotate in reverse, but since air is already flowing into motor 60 from line 60, the two opposite air pressures equalize each other and air motor 60 becomes stalled. This is in effect a braking operation for the radius control. As the radius control emerges a sufficient distance out of the pipe section, stop member 218 slips down from an area adjacent spacer 20. Then, an operator handling control rod 150 relaxes his tension on that control rod so that tension is released from valve 204 shutting off air from forward air line 66 to air motor 60. Valve 210 is maintained open so that air continues to flow from reverse air line 68 into air motor 60 causing the air motor to rotate in reverse and drive the radius control in a reverse direction. When stop member 218 comes into contact with the end of the pipe section, the operators are then assured that the radius control and its operating components are in proper position for operation of the expandible members. Then, as the rear set of. expandible members are operated, stop member 218 is withdrawn from its extended position by movement of arm 220 in slot 222 and rod 224 pivotally connecting arm 220 with shoe member 30. Each air motor of this radius control includes a conventional pressure release valve 226 which acts as an exhaust valve.

Yoke 192 includes extensions 228 and 230 (see FIG. 9), on one side, and

similar extensions

232 and 234 on the other side, which extensions are in position to contact

valve buttons

236, 238, 240, and 242, respectively, which are the control buttons for valves positioned on

brackets

244 and 246.

Extensions

228 and 232 extend slightly farther from yoke 192 than

extensions

230 and 234 for reasons that will be explained.

Valve buttons

236, 238, 240, and 242, actuate respectively

valves

248, 250, 252, and 254. Valve 248 causes communication of line 180 with air line 256 when the valve is open, thus actuating air motor to expand the rear set of shoe members 30 when valve 236 is depressed to open the valve. Valve 250 causes communication of line with line 258 when valve 250 is opened, thus permitting actuation of forward air motor 130 to cause expansion of the forward set of shoe members 30 when the valve button 238 is depressed. Likewise, valve 252 causes communication of air line 180 with air line 260 to actuate rear motor 130 in a reverse condition to retract the rear set of shoe members 30 when valve button 240 is depressed. Valve 254 causes communication of air line 180 with air line 262 to actuate forward air motor 130 in a reverse condition and retract the forward set of shoe members 30 when valve button 242 is depressed.

In operation then, rotation of shaft 182 can control the expansion and retraction of the shoe members as desired. For the forward movement of the radius control a pull on shaft 182 will disengage pin 188 from slot 186 so that pin 188 may rest upon the front surface of member 184 to give continuous forward movement of the radius control. Then the reengagement of pin 188 with slot 186 will permit the operator to rotate yoke 192. Extension member 228 on yoke 192 extends slightly farther from yoke 192 than extension member 230 so that valve 248 may be actuated independently of valve 250, and, if desired, before valve 250 is actuated. In this manner the rear set of shoe members can be expanded before the forward set is expanded so that the pipe sections may be held in position or released independently of each other. Similarly, extension 230 extends farther from yoke 192 than extension 228 so that valve button 242 may be contacted and depressed before extension 228 depresses valve button 240 in order that the forward set of shoe members 30 may be retracted from contact with the forward pipe section while the rear set of shoe members is maintained in secure position against the rear pipe section. Of course, it is seen that for certain uses of this radius control another sequence of operating the forward and rear air motors 130 may be desirable.

As a precautionary measure, a check valve 264 is included in air line 266 between air tank 16 and reserve air tank 216. During the normal operation of the radius control, air pressure flows from air tank 16 through reserve air tank 216 to valve 210 and air motor 60 in operation of the powered wheels to advance the radius control in the pipe section, and consequently reserve air tank 216 is at the same pressure as air tank 16. Then, if for any reason air tank 16 should lose its pressure, a sufficient air pressure is maintained in reserve air tank 216 to enable the operator to immediately operate the powered wheels to remove the radius control from the pipe section. It is conceivable that suitable controls can be provided to warm the operator of this possibility.

FIG. 11 describes another embodiment of this invention, a radius control which is self-powered by the power supplied by batteries carried by the radius control itself. In this embodiment tubular section 268 of the control rod serves as a conduit for electric cable 270 which includes wires for the various motors and gauges of the radius control. In FIG. 11, for the sake of simplicity, cable 270 is not shown as connected to the various components since the manner of connection is conventional and easily understood. For self-powered operation, a number of suitable storage batteries 272 are charged up and carried in compartment 274, and suitable connections are made between these batteries and the various gauges and motors of the radius control as desired. Electric motors 276 are connected switchably with wires from cable 270 and wires from batteries 272, and have a drive shaft thereof operably connected with transmission assembly 278. Transmission assembly 278 is similar in operation to transmission 128, and the expandible components of this embodiment are similar in geometry and operation to those of the embodiment described above. Another electric motor 280 is connected to wheel 34 in a manner similar to the components of FIG. 1 to drive this wheel forward or backwards as desired. Of course, the operation of this wheel can be controlled remotely as with the components of the embodiment of FIG. 1.

Since many different embodiments of this invention may be made without departing from the spirit and scope thereof, it is to be understood that the specific embodiments described in detail herein are not to be taken in a limiting sense, since the scope of the invention is best defined by the appended claims.

lclaim:

1. An internal pipe radius control comprising:

a body,

a plurality of radially extendible shoe circumferentially of said body,

a plurality of eccentric members disposed on said body inwardly adjacent said shoe members, an eccentric member I and a shoe member pivotally attached to said body on same pivotal means, each eccentric member positioned to urge outwardly a shoe member positioned on an adjacent one of said pivotal means, and

means to drive said eccentric members rotatably.

2. An internal pipe radius control as described in claim 1 wherein:

said means to drive said eccentric members rotatably inmembers arranged cludes a gear member attached to each of said eccentrics and means to drive each of said gear members rotatably. 3. An internal pipe radius control as described in claim 1 wherein:

said means to drive said eccentric cludes a sprocket attached to each of said eccentrics, chain means to drive said sprockets cooperably, and means to drive said chain means. 4. An internal pipe radius control as described in claim 3, wherein:

said means to drive said chain means includes fluid motor means positioned on said body having a drive shaft and a sprocket operably connected with said chain means. 5. An internal pipe radius control as described in claim 4 wherein: said fluid motor means is an air motor trollable. 6. An internal wherein:

said air motor is remotely controllable by control rod means removably insertable into said body to selectively actuate control members of said motor. 7. An internal pipe radius control as described in claim 6 wherein:

said body includes a powered wheel drivable tor. 8. An internal wherein:

said body includes a tensionably adjustable guide wheel. 9. An internal pipe radius control as described in claim 8 wherein: I

said body includes guide means at the front thereof to provide for proper positioning of said radius control in a pipe section. 10. An internal wherein:

said body includes an air tank communicable with said air motor to provide an air supply to drive said motor and having control means actuable by said control members of said motor.

and is remotely conpipe radius control as described in claim 5 by said air mopipe radius control as described in claim 7 pipe radius control as described in claim 9 members rotatably in-

Claims

1. An internal pipe radius control comprising: a body, a plurality of radially extendible shoe members arranged circumferentially of said body, a plurality of eccentric members disposed on said body inwardly adjacent said shoe members, an eccentric member and a shoe member pivotally attached to said body on same pivotal means, each eccentric member positioned to urge outwardly a shoe member positioned on an adjacent one of said pivotal means, and means to drive said eccentric members rotatably.

2. An internal pipe radius control as described in claim 1 wherein: said means to drive said eccentric members rotatably includes a gear member attached to each of said eccentrics and means to drive each of said gear members rotatably.

3. An internal pipe radius control as described in claim 1 wherein: said means to drive said eccentric members rotatably includes a sprocket attached to each of said eccentrics, chain means to drive said sprockets cooperably, and means to drive said chain means.

4. An internal pipe radius control as described in claim 3, wherein: said means to drive said chain means includes fluid motor means positioned on said body having a drive shaft and a sprocket operably connected with said chain means.

5. An internal pipe radius control as described in claim 4 wherein: said fluid motor means is an air motor and is remotely controllable.

6. An internal pipe radius control as described in claim 5 wherein: said air motor is remotely controllable by control rod means removably insertable into said body to selectively actuate control members of said motor.

7. An internal pipe radius control as described in claim 6 wherein: said body includes a powered wheel drivable by said air motor.

8. An internal pipe radius control as described in claim 7 wherein: said body includes a tensionably adjustable guide wheel.

9. An internal pipe radius control as described in claim 8 wherein: said body includes guide means at the front thereof to provide for proper positioning of said radius control in a pipe section.

10. An internal pipe radius control as described in claim 9 wherein: said body includes an air tank communicable with said air motor to provide an air supply to drive said motor and having control means actuable by said control members of said motor.