ZSJ/ ZXJ Type Drilling Jar ( hydraulic-mechanically) The drilling jar which is connected with drill tool and worked with drill string is a downhole stuck freeing tool in drilling operation .It is a first selected tool for directional well, complicated well and deep well.The drilling jar is consisting of ZSJ type drilling up jar and ZXJ type drilling down jar, both they can be used mutually or operated separately .The up jarring section takes use of hydraulic mechanism, the jarring force can be adjusted according to up elevating load but can not exceed the max.load for tool load rated .The down jarring section takes use of mechanical friction mechanism, the jarring force is well preadjusted by adjusting device before put into downhole.No re-adjustment can be allowed after jar is put into downhole. Thechnical specifications and parameters Parameter Type ZSJ80B ZXJ80B ZSJ76B ZXJ76B ZSJ70B ZXJ70B ZSJ62B ZXJ62B ZSJ56B ZXJ56B ZSJ46B ZXJ46B O.D.( mm) 203 197 178 160 146 121 I.D( mm) 71.4 71.4 70 57 57 51 Pull down overall length ( mm) Up 5515 5515 5424 5360 5730 5300 Down 5250 5250 5215 5215 5000 4760 Pull down strok ( mm) Up 368 368 344 344 332 305 Down 178 178 178 178 180 178 Connection API 6 5/ 8 REG 6 5/ 8 REG NC50 NC46 4 1/ 2 FH NC38 Max. tensile load ( kN) 2500 2500 2300 2200 2000 1400 Max. Working Torque ( N.m) 20 x 103 18 x 103 15 x 103 15 x 103 15 x 103 13 x 103 Rated release force for up jar ( kN) 400~ 600 400~ 600 350~ 550 300~ 450 200~ 350 150~ 250 Max.up jarring release force ( kN) 750 750 550 550 450 270 Max.down jarring release force ( kN) 600 600 550 500 400 250 All technical specifications and parameters only provides for reference.