1.Grade C sucker rods are made of high-quality alloy steel,withmoderate strength, great plasticity and good corrosion resistance etc. Grade C sucker rods can be used in weakly acidic media without sulfurized stress fracture. 

2.Grade D sucker rods are made of high-quality alloy steel, with moderate strength, great plasticity and lifespan after heat treatment. Grade D sucker rods can be used in rather deep oil wells with a corrosion-free or mildly corrosive environment. 

3.Grade K sucker rods are made ofhigh-quality alloy steel with a rather high content of Ni, with moderate strength, great plasticity and good corrosion resistance etc. Grade K sucker rods can be used in acidic media. 

4.Grade KD sucker rods combined the material of Grade K and the performances of Grade D, achieving high strength and certain corrosion resistance at the same time. Grade KD sucker rods can be used in rather deep oil wells with a corrosive environment. 

5.Grade HL sucker rods (ultra-high strength) share the same structure and size with Grade D. Through appropriate heat treatment, the strength of Grade HL is 22% greater than Grade D's, without sacrificing plasticity. Grade HL sucker rods can be used deep or large pumping oil wells with a corrosion-free or mildly corrosive environment. 

6.Grade HY sucker rods (ultra-high strength) basically share the same structure, size and parameters with Grade D, with a strength 22% greater than that of Grade D. Grade HY sucker rods are made of high-quality alloy steel. On the basis of the heat pre-treatment, the surface goes through secondary quenching by induction heating, so that the surface can bearing greater pressure and the strength and lifespan of the sucker rods are improved.