Impact sensing during jarring operations

摘要

A jarring tool operable for coupling within and generating an impact imparted to a downhole tool string. The jarring tool includes an upper housing, a lower housing, and a shaft coupled with the lower housing and extending into the upper housing. The upper housing moves axially relative to the lower housing along the shaft. The jarring tool also includes an accelerometer for detecting acceleration caused by an impact generated by movement of the upper housing away from the lower housing until corresponding impact features of the upper and lower housings collide.

主权项

1. An apparatus, comprising:
a jarring tool operable for coupling within and generating an impact imparted to a downhole tool string, wherein the jarring tool comprises:
an upper housing comprising a first bore extending longitudinally therethrough;a lower housing comprising a second bore extending longitudinally therethrough;a shaft coupled with the lower housing and extending into the first bore of the upper housing, wherein the upper housing moves axially relative to the lower housing along the shaft;a sensor system disposed within the second bore of the lower housing and comprising an accelerometer for detecting acceleration caused by an impact generated by movement of the upper housing away from the lower housing until corresponding impact features of the upper and lower housings collide; anda chassis disposed within the second bore of the lower housing, wherein the chassis comprises a curved outer surface contacting a cooperatively curved inner surface of the second bore, wherein the accelerometer is coupled to the chassis, and wherein the lower housing comprises a shoulder extending radially into the second bore and contacting the chassis to maintain an axial position of the chassis within the lower housing.