Double-Acting Hydraulic-Mechanical Drilling Jar performance


   To jar downward, apply a compression load to the jar in excess of the down-latch setting. This will release the mechanical latch and initiate the hydraulic delay sequence. Following the delay period, the jar will release, causing a downward jarring impact. Raising the drill string will re-engage the mechanical latch ready for further jarring, or to resume normal drilling as required.