A pipeline plug having a seal assembly and a slip assembly coupled to the seal assembly. The slip assembly moves from a retracted position to an expanded position when the seal assembly moves from a disengaged position to an engaged position. The slip assembly frictionally engages the internal wall of a pipe when in the expanded position. The force exerted on the pipeline plug by fluid within the pipe increases the force by which the slip assembly engages the internal wall of the pipe. The plug is removable from the pipe without damaging the plug by moving the seal assembly back to the disengaged position. A method of sealing a pipeline using the pipeline plug.

A plug (1, 301) for plugging a line (101), the plug comprising: a seal (2); a first end assembly (10, 310) located at a first end (4) of the seal (2) and a second end assembly (40) located at an opposite second end (5) of the seal (2), the first end assembly (10, 310) comprising at least one gripping member (16, 17, 316, 317) that is configured to grip an inner surface of the line (101); and an actuator (50) configured to draw the first (10, 310) and second end (40) assemblies together when there is a relative motion between the actuator (50) and the first end assembly (10, 310), characterised in that: the actuator (50) is configured to actuate the gripping member (16, 17, 316, 317), and the plug (1, 301) is arranged such that: an initial part of a motion of the actuator 50 actuates the gripping member (16, 17, 316, 317) to grip the inner surface of the line (101), thus inhibiting motion of the first end assembly (10, 310), and a subsequent part of the motion of the actuator (50), relative to the thus motion-inhibited first end assembly (10, 310), draws the second end assembly (40) toward the first end assembly (10, 310) so as to compress the seal (2) such that the seal (2) may seal against the inner surface of the line (101) thus plugging the line (101).

A plug (1, 301) for plugging a line (101), the plug comprising: a seal (2); a first end assembly (10, 310) located at a first end (4) of the seal (2) and a second end assembly (40) located at an opposite second end (5) of the seal (2), the first end assembly (10, 310) comprising at least one gripping member (16, 17, 316, 317) that is configured to grip an inner surface of the line (101); and an actuator (50) configured to draw the first (10, 310) and second end (40) assemblies together when there is a relative motion between the actuator (50) and the first end assembly (10, 310), characterised in that: the actuator (50) is configured to actuate the gripping member (16, 17, 316, 317), and the plug (1, 301) is arranged such that: an initial part of a motion of the actuator 50 actuates the gripping member (16, 17, 316, 317) to grip the inner surface of the line (101), thus inhibiting motion of the first end assembly (10, 310), and a subsequent part of the motion of the actuator (50), relative to the thus motion-inhibited first end assembly (10, 310), draws the second end assembly (40) toward the first end assembly (10, 310) so as to compress the seal (2) such that the seal (2) may seal against the inner surface of the line (101) thus plugging the line (101).

A seal assembly for a pipeline plug may include a pressure head including a forcing face. The seal assembly may include a primary tapered ring including an expansion face. The expansion face may abut the forcing face. The seal assembly may include primary seal ring. The seal assembly may include a squeezer assembly, the squeezer assembly including at least one seal face, the seal face abutting the primary seal ring. The seal assembly may include a secondary tapered ring, the secondary tapered ring including a wedge squeezer face, the wedge squeezer face abutting a wedge face of the squeezer assembly. The seal assembly may include a bowl, the bowl including a wedge face, the wedge face in abutment with an expansion face of the secondary tapered ring.

A seal assembly for a pipeline plug may include a pressure head including a forcing face. The seal assembly may include a primary tapered ring including an expansion face. The expansion face may abut the forcing face. The seal assembly may include primary seal ring. The seal assembly may include a squeezer assembly, the squeezer assembly including at least one seal face, the seal face abutting the primary seal ring. The seal assembly may include a secondary tapered ring, the secondary tapered ring including a wedge squeezer face, the wedge squeezer face abutting a wedge face of the squeezer assembly. The seal assembly may include a bowl, the bowl including a wedge face, the wedge face in abutment with an expansion face of the secondary tapered ring.

The disclosure relates to a gripping apparatus, for use in connecting to a pipe wherein the pipe defines an inside radius, the apparatus having at least one discrete gripping device mounted on a body, wherein the body is a wedge cone; an outer surface on each of the at least one discrete gripping device, wherein the outer surface has a transition surface defined by a means for reducing any sharp transition point; a collective actuation-retraction mechanism connected to the wedge cone and to each of the at least one discrete gripping device; and a collective extension-retractable mechanism connected to each of at least one discrete gripping device. The disclosure further relates to an alternative exemplary embodiment wherein the gripping apparatus further includes a spring, wherein the spring pre-biases each of the at least one discrete gripping device beyond the inside radius of the pipe to instantly grip the inside radius.

The disclosure relates to a gripping plug for use in a pipe wherein the pipe defines an inside radius, having a body of the gripping plug; an angled slot defined on the body; a first discrete gripping device slidably engaged with the angled slot and biased beyond the inside radius of the pipe; a wedge cone of the gripping plug; and a second discrete gripping device slidably engaged with the wedge code, wherein the second discrete gripping device is disengaged with the inside radius of the pipe.

A gripping apparatus for use in gripping a pipe, for holding forces, or restraining relative movement. The pipe defines an inside radius. The gripping apparatus has an outer surface where the outer surface defines a transition surface or a curve. In certain embodiments the transition surface or curve has a radius less than or equal to the inside radius of the pipe.

A sealing plug including an elastic body and a stem coaxially assembled to one another. The elastic body has a main body which is suitable for being expanded radially when pulling on the free end of the stem which emerges out of said elastic body. The elastic body also has a head attached to the main body, the head having a compressive strength less than that in the main body.

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.