... including grade C, K, D, KD, HL, HY and KH. Among them, grade C, K, D sucker rods are designed and ... HY according to SY/T5029-2006 standard, and grade KH according to company's specification. Grade C sucker rod ... it is not susceptible to sulphuric stress cracking. Grade D sucker rod is made from fine alloy steel, featured ... capacity oil-well. And grade K, KD and KH sucker rod are made from fine Cr-Ni-Mo ...