Vigor Drilling API 5CT Casing/OCTG Casing is inserted into a well bore and cemented in place to protect both subsurface formations and the wellbore from collapsing and to allow drilling fluid to circulate and extraction to take place.OCTG Casing size: 4 1/2 inch ~20 inchOCTG Casing material grade: H40, J55, K55, N80,N80Q, L80, C90, C95, T95, P110, Q125,SS95,SS110, 9%CR, 13%CRSpecial for L80 13Cr Casing/OCTG Casing is a grade 80ksi martensitic stainless steel described in API 5CT and ISO 11960 (tubulars in carbon and low alloy steels). The alloy is widely used in tubular form for /OCTG Casing/casing and tubing in standard and CO2 environment. pH, chlorides, temperature and H2S can limit its use in other environments. ISO 15156-3 limits the hardness to 22 HRC max for sour service. The alloy is almost similar to AISI 420 modified.OCTG Casing threads:BTC (Buttress Thread Casing)LTC (Long Round Thread Casing)STC (Short Round Thread Casing)Different types of OCTG Casing used in the extraction process:Surface OCTG Casing:a. It protects the well from contamination in shallow water and gas layers.b. Supports the wellhead equipment and sustains the weight of the other layers of casing.Intermediate OCTG Casing:a. Isolates different layers of pressure to facilitate normal circulation of drilling fluid and protect the production casing.b. Intermediate casing facilitates the installation of blow-out preventers, anti-leakage devices and tailpipes in the well.Production OCTG Casing (oil string)a. It is the conduit through which oil and gas pass from a below surface reservoir.b. It protects the well and separates fluids into various layers. If you are looking for competitive, high quality and fast delivery oilfield casing in stock, or if you are planning to buy casing API from one of the leading casing pipe, cra casing and tubing, premium connection casing/tubing, super 13 chromium casing, vam top tenaris sumitomo casing stock manufacturers and suppliers China, please feel free to contact VIGOR.