Abstract: An annular seal for a conduit pig includes an annular diaphragm and a separate lead support structure. The annular diaphragm is devoid of internal supports and therefore quite flexible. However, the lead support structure supports the annular diaphragm such that a piston effect can be generated through the annular seal. A brush portion for a conduit pig may include forwardly raked bristles.

Abstract: The present invention provides wellbore cleaning tool and method featuring a wiper assembly which allows fluid to bypass the tool in one direction while diverting the well fluid through a filter screen in another direction. This may be achieved by either circulation of the fluid in the wellbore or by moving the tool relative to the fluid in the wellbore. The wiper assembly includes multiple groups or series of wiper elements wherein one petal shaped element aligns with a slot to form a seal when the tool body is retrieved from the well.

Abstract: A sealing element for a pipeline pig includes rigid first and second cup supports having outer peripheral edges. A resilient sealing element protrudes beyond the outer peripheral edge of each of the first cup support and the second cup support. Means are provided for clamping the sealing element between the first cup support and the second cup support.

Abstract: A bidirectional bristle pig provides a means for collapsing or restraining the bristles so that the pig may be used in a reciprocating manner or, when the pig becomes stuck, the pig may be easily retrieved in a direction opposite that of the initial direction of travel. The bristle pig has at least one set of outwardly projecting cleaning wires or bristles located toward one end of the pig body and a sliding collar. The sliding collar moves between a first position and a second position to restrain the bristles at the desired leading end of the pig and forces the bristles downward and away from the inner wall surface of the pipeline. In the restrained state, the bristles no longer interfere with the movement of the pig in the desired direction. The sliding collar may move in response to pipeline pressure or may include a tether line.

Abstract: A trailing pig cleaning device is adapted to be dragged by a pig towing device. The cleaning device collects a predetermined quantity of debris. The cleaning device has a continuous outer surface portion of variable diameter urged into normal contact with the internal wall of the pipeline. The continuous outer surface portion presents a continuous upstream or leading edge portion for scraping debris from the cylindrical internal wall in advance of the outer surface portion. The device has a debris collecting surface portion extending radially inward from the outer surface portion for collecting the predetermined quantity of debris scraped from the cylindrical internal wall. The device has at least one debris and pipeline media bypass opening passing through the debris collecting surface portion permitting excess scraped debris to pass therethrough back into the pipeline and permitting media to pass thereby to propel the pig towing device.

Abstract: A pig traversable through a conduit to deliver a liquid, such as a coating material, having a resilient flexible, generally frustoconical sealing lip which is resiliently biased against an internal surface of the conduit and a resilient biasing member engaging and biased against an under surface of the sealing lip, biasing the sealing lip against an internal surface of the conduit. The disclosed embodiments of the resilient biasing member include annular coil springs and serpentine annular metal springs which may be U-shaped in cross-section, including a first leg received against the under surface of the sealing lip and a second leg received against the pig body portion.

Abstract: A vehicle for traversing a surface such as for carrying out an inspection, survey or maintenance operation upon that surface comprises two bodies interconnected by means to move the bodies towards and away from each other, each of those bodies being supported upon a multiplicity of resilient bristles (13; 25; 32) extending from it, the bristles of each body being mounted in groups upon bristle-carrying members (10; 23; 31) each guided for movement towards and away from the body, and fluid pressure means (25; 22; 34) to effect the guided movement of the bristle-carrying members in at least one of those directions.