US 4,654,702 A · Portable and collapsible pipe crawler

Abstract

A light-weight, portable, pipe crawler vehicle includes a four-wheeled chassis, with the sets of wheels along the opposite sides of the chassis being respectively driven by two hydraulic motors. A foldable mast is removably pivotally mounted on the chassis and carries a pneumatic cylinder which, when the mast is in its erected position, forces bearing wheels against the opposite side of the pipe to force the chassis wheels into firm frictional engagement with the pipe so that it can traverse vertical pipe sections while remaining under control. The dimensions of the vehicle are such that when the mast is folded the vehicle will fit through a 16"-diameter manway of a nuclear steam generator vessel. The chassis also carries a three-axis remote manipulator and one or two remotely-controlled video cameras. A position indicator including a star wheel and proximity sensor is disposed for rolling engagement with the pipe to sense distance travelled.

Claims20

Dependent claims

A portable self-propelled vehicle for movement along the interior surface of a pipe and receivable into the pipe through an access opening having a predetermined diameter substantially less than the diameter of the pipe, said vehicle comprising:

a carriage having a maximum lateral dimension less than said predetermined diameter, said carriage including a chassis, a plurality of wheels rotatably carried by said chassis and adapted for rolling engagement with the interior surface of the pipe, and motive means carried by said chassis for rotatably driving said wheels;
a mast mounted on said carriage for pivotal movement between a folded condition extending generally parallel to said chassis and longitudinally thereof for passage through the access opening and an erected condition extending generally perpendicular to said chassis;
fluid-actuated drive means carried by said mast;
and bearing means coupled to said drive means;
said drive means being operable for urging said bearing means into frictional rolling engagement with the interior surface of the pipe opposite the portion thereof engaged by said wheels when said mast is in the erected condition thereof positively to hold said wheels in frictional driving engagement with the pipe regardless of the orientation of said chassis.

2 more elements

Dependencies are inferred from the claim text.

Portable and collapsible pipe crawler

Life of this patent

Portable and collapsible pipe crawler

Life of this patent

Abstract

Claims20