Lhbz mechanical drilling jar is a full mechanical drilling jar, it also can be use as fishing tool. It generates upward jarring as well as downward jarring which can solve tight pull or sticking troubles during drilling. It is the first optional drilling jar for vertical well, deep well, directional well and complicated well operations. Model, lhbz121, lhbz165/159, lhbz203/197 Od mm(inch), 121 (4 3/4), 165(6 1/2) /159(6 1/4), 203(8) 197( 7 3/4) Id mm(inch), 50.8 (2), 57.2( 2 1/4), 71.4(2 13/16) Oal(locking place)mm (inch), 6370(251), 7015(276), 7310 (288) Upper stroke mm (inch), 210 ( 8 1/4), 142( 5 9/16), 145 (5 11/16) Lower stroke mm (inch), 197 (7 3/4), 172 (6 3/4), 178 (7) Conn., nc38, nc50, 6 5/8reg Max. Tensile load(mn), 1.4, 2.2, 2.5 Max. Working torque (kn. M), 13, 15, 20 Upward jarring force(kn), 450, 630, 820 Downward jarring force(kn), 230, 360, 460 Pumping area(cmâ²), 62, 100, 174