DJ Surface Bumper Jar The DJ Type Surface Bumper Jar is an effective tool for resolving the problem of frill tool in down hole.It is connected with the surface section of drill string ,the device to adjust the tonnage shall protrude from the rotary disc face,the violent down jarring to the stuck catch can be clearly seen when the surface jar makes jarring operation.The jarring strength for the tool can be easily adjusted and it is a easy operated,unique designed tool which can make continuous down jarring.The surface jar,which not only can bear heavy load and strong torque but also owns a good sealing property and withstand the mud circulation with high pump pressure,has proven to be an safe,successfully effective releasing tool through many years application.

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