... can provide sucker rods including grade C, K, D, KD, HL, HY and KH. Among them, grade C, K, D sucker rods are designed ... environment where it is not susceptible to sulphuric stress cracking. Grade D sucker rod is made from fine alloy steel, featured by ... sucker rod, having the same size and main parameter as grade D sucker rod, but their strength is capable to reach 966 ...