Casing Pipe

Products: API SPEC 5CT Casing Pipe and Tubing & Casing.
Applications: It is widely used for oil casing and tubing in oil wells
Grades: J55, K55, N80, L80-1, L80-9Cr, L80-13Cr, P110, Q125, K55 D10, L80 D10.
Special Service: Sweet Service, Sour Service, Anti-H2S, NACE MR0175/ISO15156
Produce Process: Hot Rolled, Cold Drawn, Hot Expanded.
Accessories: Pup Joint, Coupling (Coupling Stock), Blast Joint, Crossover etc.
Connection: API connection and Premium connection, like TPCQ, HSM etc.

Dimension Tolerance

Types of steel tubes	Outer Diameter		Wall Thickness
Cold-rolled tubes	Tube sizes(mm)	Tolerances(mm)	Tolerances(mm)
	＜114.3	±0.79	－12.5％
	≥114.3	－0.5％，＋1％

Chemical Composition

Standard	Grade	Chemical compositions（％）
API SPEC 5CT	J55	C	Si	Mn	P	S	Cr	Ni	Cu	Mo	V
	K55	0.34～0.39	0.20～0.35	1.25～1.50	≤0.020	≤0.015	≤0.15	≤0.20	≤0.20	/	/
	N80	0.34～0.38	0.20～0.35	1.45～1.70	≤0.020	≤0.015	≤0.15	/	/	/	0.11～0.16
	L80	0.15～0.22	≤1.00	0.25～1.00	≤0.020	≤0.010	12.0～14.0	≤0.20	≤0.20	/	/
	P110	0.26～0.395	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

Mechanical properties

Grade	Type	Total elongation under load (%)	Yield strength (min)	Yield strength (max)	Tensile strength min Mpa	Hardness Max (HRC)	Hardness Max (HBW)
J55	-	0.5	379	552	517	-	-
K55	-	0.5	379	552	655	-	-
N80	1	0.5	552	758	689	-	-
N80	Q	0.5	552	758	689	-	-
L80	1	0.5	552	655	655	23	241
L80	9Cr	0.5	552	655	655	23	241
L80	13Cr	0.5	552	655	655	23	241
C90	-	0.5	621	724	689	25.4	255
C95	-	0.5	655	758	724	-	-
T95	-	0.5	655	758	724	25.4	255
P110	-	0.6	758	965	862	-	-
Q125	All	0.65	862	1034	931	-	-

The casing is used to support the oil and gas wells of the steel pipe to ensure the completion of the whole well after the drilling process and normal operation. According to the drilling depth and geological conditions, each well has several layers of casing. The casing is cemented by cement. It is different from tubing and drill pipe. It can not be reused and consumes materials at one time. Therefore, the total casing consumption is over 70% of the well. According to the shell used, it can be divided into: conduit, surface casing, casing technology and oil casing.