Class G oil well cement, type HSR
Oil well cement finds a wide application in the exploration for and the production of oil and gas. For securing the metal casing and liners, out of which the oil and gas eventually flow. Oil well cement can also be used for sealing water wells, waste disposal wells, and geothermal wells. they fulfill the requirements for materials forming low-viscosity slurries, which remain pump able to considerable depths and can be tailored to harden rapidly once in place.
The product obtained by grinding Portland cement clinker, consisting essentially of hydraulic calcium silicates, usually containing one or more of the forms of calcium sulfate as an intergrouned addition. No addition other than calcium sulfate or water, or both, shall be interground or blended with clinker during manufacture of class G well cement. This product is intended for use as basic well cement. The chemical and physical properties of oil well cement are given relevant specifications such as the API Specification 10A.