Internal restraint device

Abstract

A restraint or gripping device for anchoring within the interior of a pipe comprises a pair of end plates adapted to be urged towards each other and a plurality of shoes, positioned between the end plates, and adapted to be moved radially outwardly as the end plates are urged together. In a further aspect, a method of restraining a pipe plug or isolation tool is provided. Also provided are assemblies for pipe isolation including an integral restraint or gripping mechanism.

1 . A restraint device for anchoring within a pipe having an inner diameter, the device comprising:
 first and second end plates, said end plates being adapted to be coaxially aligned when in use;   urging means provided on one or both end plates for urging said end plates together;   a plurality of shoes provided between the end plates;   the shoes being adapted to be moved radially outwardly as the end plates are urged together.   
     
     
         2 . The device of  claim 1  wherein the shoes comprise curved plates having an outer surface for engaging the inner wall of the pipe. 
     
     
         3 . The device of  claim 2  wherein the shoes are generally equidistantly spaced over the circumference of the pipe. 
     
     
         4 . The device of  claim 3  wherein opposed faces of first and second end plates include a beveled outer edge for engaging the plurality of shoes. 
     
     
         5 . The device of  claim 3  wherein the plurality of shoes have an inner surface directed radially away from said shoe outer surface and wherein said inner surface includes oppositely beveled edges to engage said beveled edges of the end plates. 
     
     
         6 . The device according to  claim 1  wherein said means for urging comprises a mechanical mechanism, a hydraulic mechanism, or a magnetic mechanism. 
     
     
         7 . The device of  claim 6  wherein said mechanical mechanism comprises a plurality of bolts extending between the end plates. 
     
     
         8 . The device according to  claim 1  wherein said device is adapted to engage a pipe plug or isolation tool. 
     
     
         9 . The device according to  claim 1  further comprising at least one annular boss positioned between the end plates and wherein said shoes are provided on opposite sides of the boss. 
     
     
         10 . The device of  claim 9  wherein said boss includes an outer diameter with oppositely directed bevels for engaging respective shoes. 
     
     
         11 . A restraint system comprising one or more of the devices according to  claim 1 , wherein said one or more devices are positioned within a pipe adjacent to a pipe plug or isolation tool. 
     
     
         12 . A method of restraining a pipe plug or isolation tool comprising:
 securing the pipe plug or isolation too within a pipe at a desired position;   and securing a restraint device according to  claim 1  within the pipe adjacent to said plug or tool.   
     
     
         13 . The method according  claim 12  further comprising connecting said restraint device to the pipe plug or isolation tool. 
     
     
         14 . An assembly for isolating an internal segment of a pipe, the assembly comprising:
 a shaft having a first end and a second end;   a first boss connected to the first end of the shaft;   a sleeve slidably and coaxially provided over the shaft, the sleeve having a first end and a second end, wherein the first end of the sleeve is directed to the first end of the shaft;   a second boss secured to the first end of the sleeve;   first and second annular bodies provided between the first and second bosses, the first annular body positioned adjacent the first boss and the second annular body positioned adjacent the second boss;   a first resilient sealing member positioned between the first boss and the first annular body and a second resilient sealing member positioned between the second boss and the second annular body;   a plurality of shoes provided between the first and second annular bodies, the shoes being adapted to be urged radially outwards when the device is in use;   a nut, provided at the second end of the shaft for urging the sleeve towards the first end of the shaft.   
     
     
         15 . The assembly of  claim 14  further comprising a means for filling and pressurizing a segment of the pipe constrained by the first and second sealing members and the first and second annular bodies. 
     
     
         16 . An assembly for isolating an internal segment of a pipe, the assembly comprising:
 a first boss and a second boss;   an annular body provided between the first and second bosses;   a first resilient sealing member positioned between the annular body and the first boss;   a second resilient sealing member positioned between the annular body and the second boss;   a plurality of tie rods extending from the first boss towards the second boss, the tie rods being adapted to extend through the annular body and the second boss;   a plate provided adjacent the second boss on a side opposite to the annular body, the plate including a plurality of bolt holes through which the tie rods are extendable;   two or more shoes provided between the second boss and the plate, the plates being adapted to be moved radially outwardly upon urging of the plate towards the second boss; and,   two or more first nuts provided for engaging the tie rods on a side of the plate opposite the shoes for urging the plate in a direction towards the first boss.   
     
     
         17 . The assembly of  claim 16  wherein the shoes include a beveled edge for engaging an oppositely beveled edge of the second boss or the plate. 
     
     
         18 . The assembly of  claim 17  wherein the plate includes a beveled outer edge for engaging the beveled edges of the shoes. 
     
     
         19 . The assembly of  claim 17  wherein the second boss includes a beveled outer edge for engaging the beveled edges of the shoes. 
     
     
         20 . The assembly of  claim 16  further comprising second nuts provided on the tie rods adjacent to the second boss, and for urging the second boss in a direction towards the first boss.