... , high downhole speed and long working life 9 7/8" IADC537G is a regular types, we found ... is about 20 days, Eastern North Amerca is about 32 days, Eastern Africa is about 30 days, South ... is about 30 days. To Japan is about 7 days, to East-south Asia is always less ... sizes: 60mm,65mm,76mm,93mm,95mm,98mm(3 7/8”), 114mm,118mm(4 5/8”),120mm(4 ... 1/2”)190.5mm(7 1/2”),193.6mm(7 5/8”),200.0mm(7 7/8”)215.9mm(8 ...