Two-action Drill Accelerator Type SZJQ can be stored energy by hydraulic spring. It should be applied with Model QY? Hydraulic Drilling Jar 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.
ABB Motor Protection Devices 1SAZ321201R1005
ABB Motor Protection Devices 1SAZ211201R2028-LKH
ABB Air Circuit Breaker 1SDA114041R1 
