DL offers four different types of liners for all popular mud pumps to suit any drilling condition,including Premium Chromium Liners,Ceramic Liners,Chromium-plated Liners and Hardened Liners. Premium Chromium Liners DL Chromium Liners combine the strength of forged steel outer shell with the abrasion and corrosion resistence of a high chromium iron inner sleeve.These liners feature a centrifugally cast high chrome iron sleeve which is machined and heat treated to a minimum uniform bore hardness of 62 RC.Each liner is machined to close tolerances to assure ease of installation and long liner life with the inside diameter of these premium liners honed to a mirror-like finish for smooth even wear during the life of liner.Dongli premium liners are made for superior performance under tough corrosive and abrasive conditions. Ceramic Liners Dongli Ceramic Liners combine the strength of forged steel outer shell with the abrasion and corrosion resistence of a inner sleeve. Chromium-plated Liners Chromium-plated Liners made from premium forged steel with the core plated by chrome.. The chromium-plated Liners had hardening characteristics 58 to 62 Rockwell C hardness. Hardened Liners Dongli hardened Liners offer economy in a liner that is made for normal to mildly corrosive mud conditions.These liners are hardened and heat treated under strict quality control to a minimum of 60 RC hardness and a depth of 125 inches. Each liner honed to a mirror-like finish for smooth even wear during the life of liner and is machined to close tolerances to assure easy installation and long life.