Steel Casing Pipes
Steel casing pipe or tube used in drilling well or any underground installation is called casing tube or pipe. Steel Casing Pipe, also known as encasement pipe, is most commonly used in underground construction to protect utility lines of various types from getting damaged.
API Spec 5CT – Specification 5CT/ISO 11960, Specification for Casing and Tubing, Eighth Edition, Petroleum and natural gas industries-Steel pipes for use as casing or tubing for wells.
Casing pipes are used for casing oil & gas wells. In casing a large diameter pipe is assembled and is inserted into a drilled section of a bore-hole.
Why is casing done?
· It prevents contamination of fresh water
· It provides stronger upper foundation for dipper drill
· Enables smooth bore for installing equipment
· Seals high pressure zone surface to ward from getting blown off
Benefits of steel casing pipe:
Casing pipes manufactured out of steel are smelted in the electric furnace, treated with synthetic slags and cast by continuous casters. This process ensures the achievement of chemically pure steel with reference to sulphur and phosphor contents providing high tensile, ductility and corrosion resistance properties of pipes to be operated at low temperatures in various corrosion media. Pipes are heat-treated in a computerized walking beam furnace.
Steel grades and heat treatment regimes applied allow high-strength pipe to be obtained. Steel casing pipes and tubing are applied to furnishing and installing cased tunnels, where they indicate to pass other utilities or obstructions without open excavation. Steel casing pipes and tube have smooth wall and a minimum yield strength of 35,000 psi. Corrosion-proofing water-based paint is applied on the outside pipe surface to protect against atmospheric corrosion during transportation and storage.
The pipes can be delivered with metal or composite caps at both ends for thread protection.