API 5CT Casing and Tubing

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Update time : 2026-04-28 08:44:35

　　The main steel grade of API 5CT: API 5CT J55, API 5CT K55, API 5CT N80, API 5CT L80, API 5CT P110. This International Standard is applicable to the following connections in accordance with ISO 10422 or API Spec 5B:

　　short round thread casing (STC);

　　long round thread casing (LC);

　　buttress thread casing (BC);

　　extreme-line casing (XC);

　　non-upset tubing (NU);

　　external upset tubing (EU);

　　integral joint tubing (IJ).

　　For such connections, this International Standard specifies the technical delivery conditions for couplings and thread protection. For pipes covered by this International Standard, the sizes, masses, wall thicknesses, grades and applicable end finishes are defined. This International Standard may also be applied to tubulars with connections not covered by ISO/API standards.

　　Chemical Composition

Grade	C≤	Si≤	Mn≤	P≤	S≤	Cr≤	Ni≤	Cu≤	Mo≤	V≤	Als≤
API 5CT J55	0.34-0.39	0.20-0.35	1.25-1.50	0.020	0.015	0.15	0.20	0.20	/	/	0.020
API 5CT K55	0.34-0.39	0.20-0.35	1.25-1.50	0.020	0.015	0.15	0.20	0.20	/	/	0.020
API 5CT N80	0.34-0.38	0.20-0.35	1.45-1.70	0.020	0.015	0.15	/	/	/	0.11-0.16	0.020
API 5CT L80	0.15-0.22	1.00	0.25-1.00	0.020	0.010	12.0-14.0	0.20	0.20	/	/	0.020
API 5CT J P110	0.26-035	0.17-0.37	0.40-0.70	0.020	0.010	0.80-1.10	0.20	0.20	0.15-0.25	0.08	0.020

Mechanical Properties of API 5CT

Steel Grade	Yield Strength (Mpa)	Tensile Strength (Mpa)
API 5CT J55	379-552	≥517
API 5CT K55	≥655	≥517
API 5CT N80	552-758	≥689
API 5CT L80	552-655	≥655
API 5CT P110	758-965	≥862

　　API 5CT Casing steel pipes The main steel grade of API 5CT: API 5CT J55,API 5CT K55,API 5CT N80,API 5CT L80,API 5CT P110. Packing: Bare/bundles/crates/crate protection at the both sides of tubes or as per customers’ requirements Please feel free to contact us if you have any questions.Email : pipe@stpipefitting.cn

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