Bolu manufactures bi-metal liners and ceramic zirconia liners. Bolu also supplies genuine rubber and urethane liner seals. All our liner products are exchangeable with oem products and meet or exceed api-7k standards. Ceramic zirconia liners High strength alloy steel outer hull Ceramic inner sleeve Better resistance to heat and corrosion. Exchangeable with oem products Meet or exceed api-7k standards For more details, please feel free to tell us. Established in 1998, botou bolu petroleum machinery factory is a professional manufacturer & supplier of mud pumps & parts. Bolu petroleum can offer a full line of mud pumps & parts together with casing heads, drilling pipe join tools, tdb hydraulic profile control water plugging pump & parts , x-trees and many other oilfield drilling tools. Bolu petroleum has been granted the api certification. Products are exported to america , middle east, etc. Bolu petroleum is looking forward to being partners with you around the world.