The Griffith Jar Tester is a rugged, self-contained unit
designed to test the proper operation of fishing jars, drilling
jars, and other downhole drilling tools. The horizontal main
frame and attached hydraulic cylinder efficiently applies
tension and compression forces in direct axial alignment with
the work piece.
The Griffith Jar Tester is designed to stand alone or to
be an accessory to the Griffith Torquemaster. The auxiliary
circuit on the Torquemaster console will provide the proper
hydraulic power and control for effective operation of the
Jar Tester. The Jar Tester can also be powered with its own
hydraulic system or with an existing source providing it has
To test a tool in the jar tester, test nubbins are first
threaded into the tool connections. The tool can then be
placed into the jar tester frame after the tail carriage and
head carriage have been adjusted to accommodate tool length.
Tension or compression force can then be applied to the tool
through the test nubbins. The force being applied to the tool
can be varied using the "torque control" valve on the
Torquemaster (or equivalent) and force readings can be
determined by comparing "PSI" (indicated on torque gauges or
equivalent) to a Griffith supplied conversion chart.