DOWNHOLE TOOL FOR OPENING A TRAVELLING VALVE ASSEMBLY OF A RECIPROCATING DOWNHOLE PUMP

摘要

A downhole tool for opening a travelling valve assembly of a downhole pump isdisposed withthe travelling valve assembly within a pump barrel, and includes asubstantially cylindricalhousing and a piston. The housing defines an axial bore extending from abottom opening forfluid communication with the pump barrel, a radial port for fluidcommunication between theaxial bore and the pump barrel, and a channel formed in the outer surface ofthe housing for fluidcommunication between the radial port and the travelling valve assembly. Thepiston occludesthe axial bore above the radial port, and in response to an upward pressureexerted by aproduction fluid below the piston, slides upwardly within the axial bore toengage and open avalve member of the travelling valve assembly.