API 5CT Casing Pipe - Casing Specificaton & Trade Terms
| Model | Casing |
|---|
| Place Of Origin | China |
|---|
| Price Term | EX-Work |
|---|
| Payment Term | T/T |
|---|
Brief Description:
Outside Diameter: 5-1/2 to 20 Inches, Steel Grade: J55, K55, N80, L80, P110 End-Finish: PE, STC, LTC, BTC Length Range: R1/R2/R3 Manufacture Process: Seamless or Electric-Welded (Electric-Resistance or Electric-Induction Welded)
Product Details:
Standard: API Specification 5CT, Ninth Edition, July 2011
Outside Diameter: 5-1/2 to 20 Inches (114.30-508.00mm)
Steel Grade: J55, K55, N80, L80, P110
Range Length: R1 (4.88-7.62metres), R2 (7.72-10.36metres), R3 (10.36-14.63metres)
Manufacture Process: Seamless or Electric-Welded (Electric-Resistance or Electric-Induction Welded)
Type of Threading: STC (Short Round Thread), LTC (Long Round Thread), BTC (Buttress Thread), or PE (Plain End, unthreaded).
Casing is a large-diameter pipe that serves as the structural retainer for the walls of oil and gas wells, or wellbore. It 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. The following different types of casing are used in the extraction process:
Surface casing
- Protects the well from contamination in shallow water and gas layers.
- Supports the wellhead equipment and sustains the weight of the other layers of casing.
Intermediate casing
- Isolates different layers of pressure to facilitate normal circulation of drilling fluid and protect the production casing.
- Intermediate casing facilitates the installation of blow-out preventers, anti-leakage devices and tailpipes in the well.
Production casing (oil string)
- It is the conduit through which oil and gas pass from a below surface reservoir.
- It protects the well and separates fluids into various layers.
For the manufacture of casing, green pipes are threaded on each end at first. The threading is then inspected and, if necessary, rethreaded to ensure that the thread accurately connects to the coupling. The casing are strengthened by surface treatment and are subject to various inspections, including drifting and hydrostatic tests before they are coated and packaged into casing.
