Method and apparatus for removal of pigs, deposits and other debris from pipelines and wellbores
A carrier assembly having at least one sealing cup, a fluid bypass and adjustable wash nozzles, as well as a spear assembly having a central through bore, are attached to the distal end of a length of continuous tubing and inserted in to the flow bore of a pipeline. Fluid is pumped through the annular space between the carrier assembly and the pipeline, providing motive force for advancing the carrier assembly within the pipeline. Fluid can bypass the carrier assembly, enter the central bore of the spear assembly, and return to the surface through the central bore of the continuous tubing. A stuck pig or other obstruction is speared, and thereafter retrieved from the pipeline on the continuous tubing.
1. An apparatus for removing obstructions from a pipeline comprising:
a first body member having a flow bore extending therethrough, and at least one flow channel having an inlet and an outlet disposed through said first body member, wherein the flow bore is configured to allow flow only in a first flow direction through the first body member, and the at least one flow channel is configured to allow flow only in a second flow direction through the first body member from the inlet to the outlet, the second flow direction being opposite to the first flow direction, and the first flow direction being in a upstream direction and the second flow direction being in a downstream direction;
at least one sealing cup disposed on said body member between the inlet and outlet of said at least one flow channel, sealingly engaging the inner surface of said pipeline;
a nozzle on the outlet of said at least one flow channel;
first and second knuckle joints disposed upstream of the at least one sealing cup; and
a second body member disposed between the first and second knuckle joints.
2. The apparatus of claim 1 , wherein said at least one sealing cup further comprises:
a rigid frame; and
at least one elastomer attached to said rigid frame.
3. The apparatus of claim 1 , further comprising a screen assembly disposed over the inlet of said at least one flow channel.
4. The apparatus of claim 1 , wherein said nozzle comprises an adjustable wash nozzle.
5. The apparatus of claim 1 , wherein said nozzle is oriented at an angle between 40 and 50 degrees relative to the inner surface of said pipeline.
6. The apparatus of claim 1 , further comprising a spear assembly having a first end, a second end and a spear assembly flow bore extending therethrough, wherein said first end is connected to first body member, said second end forms a point, and said spear assembly flow bore is in fluid communication with the flow bore of said first body member.
7. The apparatus of claim 6 , further comprising at least one brush connected to the outer surface of said spear assembly.
8. The apparatus of claim 6 , further comprising a relief valve having open and closed positions, disposed between said first and second ends of said spear assembly, said relief valve permitting fluid communication between the outer surface and flow bore of said spear assembly when in an open position.
9. The apparatus of claim 6 , further comprising a third knuckle joint between said first body member and spear assembly.
10. A method for removing an obstruction from a pipeline comprising:
connecting an obstruction removal apparatus to a length of continuous tubing, said obstruction removal apparatus comprising:
a first body member having a flow bore extending therethrough, and at least one flow channel having an inlet and an outlet disposed through said first body member, wherein the flow bore is configured to allow flow only in a first flow direction through the first body member, and the at least one flow channel is configured to allow flow only in a second flow direction through the first body member from the inlet to the outlet, the second flow direction being opposite to the first flow direction;
at least one sealing cup disposed on said body member between the inlet and outlet of said at least one flow channel, sealingly engaging the inner surface of said pipeline;
a nozzle on the outlet of said at least one flow channel;
first and second knuckle joints disposed upstream of the at least one sealing cup; and
a second body member disposed between the first and second knuckle joints and
conveying said obstruction removal apparatus into a pipeline;
pumping fluid into an annular space formed between an inner surface of the pipeline and the obstruction removal apparatus, wherein the pumped fluid flows through the at least one flow channel in the second flow direction and out the nozzle, thereby maintaining a pre-set, substantially constant pressure across the carrier assembly;
engaging an obstruction; and
removing said obstruction from said pipeline.
11. The method of claim 10 , further comprising returning at least a portion of the fluid through said continuous tubing, wherein at least a portion of the fluid flowing out the nozzle flows into the flow bore in the first flow direction, the flow bore being in fluid communication with the continuous tubing.
12. The method of claim 10 , wherein said at least one sealing cup further comprises:
a rigid frame; and
at least one elastomer attached to said rigid frame.
13. The method of claim 10 , wherein said obstruction removal apparatus further comprises a screen assembly disposed over the inlet of said at least one flow channel.
14. The method of claim 10 , wherein said nozzle comprises an adjustable wash nozzle.
15. The method of claim 10 , wherein said nozzle is oriented at an angle between 40 and 50 degrees relative to the inner surface of said pipeline.
16. The method of claim 10 , wherein the apparatus further comprises a spear assembly having a first end, a second end and a spear assembly flow bore extending therethrough, wherein said first end is connected to said first body member, said second end is pointed, and said spear assembly flow bore is in fluid communication with the flow bore of said first body member.
17. The method of claim 16 , wherein said obstruction removal apparatus further comprises at least one brush connected to the outer surface of said spear assembly.
18. The method of claim 16 , wherein said obstruction removal apparatus further comprises a relief valve having open and closed positions, disposed between said first and second ends of said spear assembly, said relief valve permitting fluid communication between the outer surface and flow bore of said spear assembly when in an open position.
19. The method of claim 16 , wherein said obstruction removal apparatus further comprises a third knuckle joint between said first body member and spear assembly.
20. An apparatus for removing obstructions from a pipeline comprising:
a first body member having a flow bore extending therethrough, and at least one flow channel having an inlet and an outlet disposed through said first body member, wherein the flow bore is configured to allow flow in a first flow direction through the first body member, and the at least one flow channel is configured to allow flow in a second flow direction through the first body member from the inlet to the outlet, the second flow direction being opposite to the first flow direction, and the first flow direction being in an upstream direction and the second flow direction being in a downstream direction;
a check valve system comprising a relief inlet fluidly coupled to the flow bore and configured to allow flow from the inlet into the flow bore in the first flow direction;
at least one sealing cup disposed on said body member between the inlet and outlet of said at least one flow channel, sealingly engaging the inner surface of said pipeline;
a nozzle on the outlet of said at least one flow channel;
first and second knuckle joints disposed upstream of the at least one sealing cup; and
a second body member disposed between the first and second knuckle joints.