Hydraulic Jar (HJ) is a bi-directional drilling jar incorporating hydraulic delay without a latch mechanism. This type of jar allows operator to apply variable impact in both the up and down directions. The HJDA is intended for use in highly deviated or high friction wells where conditions may prevent applying sufficient force to release a mechanical latch.

The HJ is hydraulically controlled and jars in both directions with impact force controlled by the operator.
Impact force is controlled by a metering device that ensures consistent delay times over the full range of operating temperatures.
The HJ operates via a simple up and down motion and is unaffected by torque.
Maximum efficiency in wells with complex trajectory profiles and with high deviation from vertical, horizontal and slant wells, ERD wells.