Pumpdown assist tool for wireline operations

Abstract

A pumpdown assist device has an outer housing comprising a top connection, a spring housing, a piston housing and a bottom connection, all defining a central bore; a mandrel disposed and slidably moveable within the central bore between a run-in-hole (RIH) position and a pull-out-of-hole (POOH) position, the mandrel comprising a head portion, a central portion and a bottom stem, all defining a central passage, wherein the head portion comprises a flow restriction from the top connection central bore; a piston connected to the mandrel and having a sloped ramp surface; a plurality of pads slidably disposed on the piston ramp surface and which are transversely moveable through pad cutouts defined by the piston housing; and biasing means disposed within the spring housing, for urging the mandrel in its POOH position. The device is installed into a bottom hole assembly (BHA) and is urged into a wellbore by pumping down fluid. When fluid pressure within the device top connection exceeds the biasing means force, the mandrel is shifted to the RIH position and the pads are deployed outwards. Sufficient flow rate is then maintained to maintain deployment pressure in the device top connection until the BHA reaches a desired depth. The pads may then be retracted into a POOH position by reducing pumpdown flow rate.

Dependencies are inferred from the claim text.