... bearing life5.seal and lubracation:Premium O-ring,optimal seal compression and curved seal structure can enhance the seal performance.The ... with different tooth shape,tooth density and tooth exposure hight.8.all IADC code available in our company CS 9 ... 1/2”),193.6mm(7 5/8”),200.0mm(7 7/8”)212.7mm(8 3/8”),215.9mm(8 1/2”),222.2mm8 3 ... 2”),244.4(9 5/8”),250.8(9 7/8”)269.8(10 5/8”),295.3(11 5/8”)311.1(12 1/4 ...