Patent ID: 9512688
Filing Date: 2016-12-06
CPC Classification: E21B

Claim Text:
1. A downhole tool extending in a longitudinal direction, comprising: a tool housing, an arm assembly movable between a retracted position and a projecting position in relation to the tool housing, the arm assembly comprising an arm member connected with the tool housing in one end, the arm assembly including a rotational part to propel the downhole tool in a well, the rotational part including a wheel ring structured to provide traction against a side wall of a well casing, an arm activation assembly arranged in the tool housing for moving the arm assembly between the retracted position and the projecting position, and a pump for circulating hydraulic fluid, wherein the arm assembly comprises a hydraulic mechanism at least partly arranged in the rotational part, and an internal fluid influx channel provided in the arm member and extending to the wheel ring, the internal fluid influx channel being in fluid communication with the hydraulic mechanism for supplying hydraulic fluid from the pump to the hydraulic mechanism for retracting and projecting the arm assembly, driving said hydraulic mechanism and rotating said rotational part and the wheel ring.