1.K,D,HL grade ,high strengh and super-high strengh Sucker rod 2,The main dimensions of sucker rod have 5/8",3/4",7/8",1" Mechanical Properties of Type-D Sucker Rods Tensile StrengthYield StrengthExtension Radioδ%Reduction of cross-sectionφ%Impact Flexibility α KIL/cm²793-965≥620≥10≥50≥58.8Mechanical Properties of Type HY Sucker Rods Tensile Strengthσb MPaRigidityODmmSurface residual press ...