Model ?ZJQ? Drilling Accelerator can be stored energy by hydraulic spring as to increase the jarring force for Hydraulic Jar. It should be applied with Hydraulic Drilling Jar Type QY? jointly. The drill collar and Hydraulic Jar (below the Drill Accelerator ) can function an accelerated effect when jarring operates as for making the stuck point gain more jarring force that can increase force for two times at the highest.
ABB Motor Protection Devices 1SAZ211201R2028-LKH 
