Abstract: A vehicle (1) for travelling along a conduit (2) such as a pipeline having fluid flowing therein is disclosed. The vehicle comprises a first body carrying a first set of retractable bristles (12) for engaging an internal wall of the conduit such that the bristles resist movement of the first body in a first direction more than in a second direction, and a second set of retractable bristles (13) for engaging the internal wall of the conduit such that the bristles resist movement of the first body in the second direction more than in the first direction. A thread follower (16) carries a third set of resilient bristles (18) for engaging the internal wall of the conduit such that the bristles resist movement of the thread follower in the first direction more than in the second direction. A turbine (5) is actuated by fluid flow in the conduit to cause rotation of a reverse traverse screw (14) to move the first body and thread follower towards and away from each other.

Abstract: A vehicle (1) for travelling along a conduit (2) such as a pipeline having fluid flowing therein is disclosed. The vehicle comprises a first body carrying a first set of retractable bristles (12) for engaging an internal wall of the conduit such that the bristles resist movement of the first body in a first direction more than in a second direction, and a second set of retractable bristles (13) for engaging the internal wall of the conduit such that the bristles resist movement of the first body in the second direction more than in the first direction. A thread follower (16) carries a third set of resilient bristles (18) for engaging the internal wall of the conduit such that the bristles resist movement of the thread follower in the first direction more than in the second direction. A turbine (5) is actuated by fluid flow in the conduit to cause rotation of a reverse traverse screw (14) to move the first body and thread follower towards and away from each other.

Abstract: A conduit gripping apparatus (1) for a vehicle travelling along a conduit such as an oil pipeline is disclosed. The apparatus comprises a housing (2) having a plurality of surface engaging elements (3) carrying sets of resilient bristles (4). The bristles engage a surface of the conduit and resist relative movement of the corresponding surface engaging element (3) and the surface of the conduit in a first direction along the conduit more than in a second direction opposite to said first direction. Each surface engaging element is adapted to execute reciprocating movement, relative to the housing (2), having a component substantially parallel to said first and second directions, and not all of said surface engaging elements execute said reciprocating movement in phase with each other, such that the surface engaging elements remain in contact with the surface of the conduit during said reciprocating movement.

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.

Abstract: A vehicle (1) for travelling along a conduit (2) having fluid flowing therein is described. The vehicle comprises a forward set of resilient bristles (12) and a rear set of bristles (18) which are adapted to move towards and away from the forward bristles (12). The forward bristles (12) engage the surface of the conduit (2) and apply a greater gripping force when they are moving towards the mar bristles (18) than when they are moving away from the rear bristles (18). Similarly, the rear bristles (18) apply a larger gripping force to the surface of the conduit (2) when they are moving away from the forward bristles (12) than when they are moving towards the forward bristles (12).

Abstract: A vehicle for traversing a surface, for example for carrying out an inspection, survey or maintenance operation upon that surface, includes two or more bodies interconnected by structure for moving the bodies towards and away from each other, each of the bodies being supported upon a multiplicity of resilient bristles extending from it. By relative movement of the bodies, the vehicle is able to traverse the surface, which may be flat or curved, for example the internal or external surface of a tubular conduit such as a tunnel, shaft or pipe.

Abstract: A vehicle, designed to move across an external curved surface such as that of a pipe or cable, for example to monitor the condition of the surface or enable the application of a treatment to the surface, comprises two generally hollow bodies, interconnected by means to move the bodies towards and away from each other, each body having generally parallel, generally flat resilient members each having a generally central aperture, which apertures are in general alignment.