Hydraulic Impact Apparatus and Methods

摘要

A hydraulic jar coupled between opposing first and second portions of a downhole tool string. The hydraulic jar includes a housing comprising a shoulder protruding radially inward from an internal surface of the housing, a shaft disposed within the housing, a piston fixedly positioned about the shaft and fluidly sealed against the shoulder, and a pressure relief device. The housing and the shaft move axially relative to each other and the shoulder axially interposes first and second portions of an annulus formed between the shaft and the housing. The pressure relief device controls fluid flow from the first annulus portion to the second annulus portion based on a pressure of the fluid in the first annulus portion relative to a set pressure of the pressure relief device.

主权项

1. An apparatus, comprising:
a hydraulic jar coupled between opposing first and second portions of a downhole tool string, wherein the hydraulic jar comprises:
a housing comprising a shoulder protruding radially inward from an internal surface of the housing;a shaft disposed within the housing, wherein the housing and the shaft move axially relative to each other, and wherein the shoulder axially interposes first and second portions of an annulus formed between the shaft and the housing;a piston fixedly positioned about the shaft and fluidly sealed against the shoulder; anda pressure relief device controlling fluid flow from the first annulus portion to the second annulus portion based on a pressure of the fluid in the first annulus portion relative to a set pressure of the pressure relief device.