API 5CT Data Sheet – Casing & Tubing Properties and Tolerances

The following tables provide reference data for API 5CT casing & tubing, including mechanical properties, chemical composition, dimensional tolerances, and standard length ranges. This information is for preliminary engineering review only. Final design must use minimum wall thickness for calculations and verify all data against the latest API 5CT specification and manufacturer's test reports.

Standard: API SPEC 5CT
Products: Seamless Casing and Tubing

Applications: It is widely used for oil casing and tubing in oil wells
Grades: J55, K55, N80, L80, P110 etc. 

Mechanical properties:

Standard	Grade	Tensile Strength（MPa）	Yield Strength（MPa）
API SPEC 5CT	J55	≥517	379～552
	K55	≥517	379～552
	N80	≥689	552～758
	L80(13Cr)	≥655	552～655
	P110	≥862	758～965

Note: YS = Yield Strength, TS = Tensile Strength. 1 MPa ≈ 145 psi.

Chemical Composition:

 

Dimensional Deviation:

Dimensional Deviation
Items		Allowable Deviation
Out Diameter	Pipe Body	D≤101.60mm±0.79mm
		D≥114.30mm +1.0%
		-0.5%
Wall Thickness		-12.5%
Weight	Each Piece	+6.5%
		+3.5%

Note: Dimensional tolerances are in accordance with API 5CT. Wall thickness design must use the minimum allowable value for load calculations.

Length Range:

API 5CT specifies three standard length ranges to reduce the number of connections and optimize field handling. R-2 is the most commonly used range.

Length
Item	Range  1	Range 2	Range 3
Tubing	6.10-7.32m	8.53-9.75m	-
Casing	4.88-7.62m	7.62-10.36m	10.36-14.63m

 

▶ For a complete guide to API 5CT standards, steel grades, and selection criteria, see our [API 5CT Standard – Casing and Tubing Specifications Guide].

Read more: 

●  OCTG Casing Pipe Size Chart

●  Steel Grades of OCTG Casing - A Comprehensive Guide

●  Casing Inspection Methods