Certificate of utility model patent for a drilling fluid vacuum degassing device
Certificate of utility model patent for a guide frame pressing plate of the water filling valve in drilling pump.
Certificate of utility model patent for a hydraulic cylinder of drilling pump
Certificate of utility model patent for a spray pipe fixing device used in drilling pump
Certificate of utility model patent for a auxiliary device used for drilling pump piston dismounting
Certificate of utility model patent for a forced lubrication device used for drilling pump
Certificate of utility model patent for a sealing device of the intermediate rod of drilling pump
Certificate of utility model patent for a combined sealing device for the principal axis of drilling pump 
Certificate of utility model patent for a corrugated pipe booster drilling pump
Certificate of utility model patent for a structure-modified drilling pump piston
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