Pup Joint for Releasing Sidewall Contact of Stratigraphic Test Device and Apparatus

Abstract

A pushing and jam-releasing pup joint of a formation tester comprises a first jam-releasing arm (1), a first three-way reversing valve (V1), a two-way reversing valve (V2) and a third three-way reversing valve (V4), a withdrawal cavity (Q11) of the first jam-releasing arm (1) is connected with the first three-way reversing valve (V1) which can communicate with an energy accumulation cavity (NQ) of an energy accumulator and the two-way reversing valve (V2), the two-way reversing valve (V2) can be communicated with a pressure oil main line (G2) of a hydraulic system, and an extension cavity (Q12) of the first jam-releasing arm (1) is connected with the third three-way reversing valve (V4) which can communicate with the pressure oil main line (G2) and a return oil main line (G1) of hydraulic system. Jam-releasing pup joint effectively solves the problem of jam release when mud adheres to EFDT and makes same jammed.

Dependencies are inferred from the claim text.