API 5CT Casing and Tubing Specification

What is API 5CT?

At UNIASEN, we offer premium API 5CT Casing and Tubing designed to meet the rigorous demands of the oil and gas industry.

Our steel pipes are crafted with precision, ensuring the highest quality in casing, tubing, and accessory materials. With three product specification levels (PSL-1, PSL-2, and PSL-3), we provide a range of options tailored to your specific needs.

Whether it’s the robustness of PSL-3 or the foundational quality of PSL-1, you can trust our products to deliver exceptional performance and reliability.

Choose UNIASEN, and invest in steel pipes that stand the test of time.

Specification

Our API 5CT Casing and Tubing come with comprehensive specifications that include dimensions, production procedures, steel grades, surface coatings, end types, joint methods, and machining services. You benefit from a wide array of sizes, masses, and wall thicknesses, along with various grades and applicable end finishes. By partnering with us, you also have the flexibility to apply this standard to other plain-end pipe sizes and wall thicknesses, ensuring a customized solution that fits your unique requirements.

Production Standard: API 5CT
Procedure: ERW, SMLS
Dimensions: Casing Pipe 114.3 – 508mm; Tubing Pipe 26.67 – 114.3mm

Casing Pipe 4 1/2”- 20″ ;

Tubing Pipe 1.05” -4 1/2”

Thickness: 5.21mm – 22.22mm
Unit Length: Casing Pipe 4.88 – 14.63 mtrs, Tubing Pipe 6.10 – 12.80 mtrs
Steel Grade: API 5CT H40, API 5CT N80-1

API 5CT J55, API 5CT L80Cr

API 5CT K55, API 5CT C90-1

API 5CT N80, API 5CT T95-1

API 5CT N80Q, API 5CT C110

API 5CT R95, API 5CT P110

API 5CT L80, API 5CT Q125

Surface Coating: Varnishing, Black Varnishing
End Type:Plain end, Short Round Thread, Long Round Thread, Buttress Thread, Extreme-line.

Plain end, Non-upset Threaded and Coupled, External upset Threaded and couple,Intergral

JointJoint Method: Coupling
Further Processing: Threading

Dimension

UNIASEN’s API 5CT Casing and Tubing are available in a multitude of dimensions that adhere to international standards. Our dimension table includes precise details on sizes, masses, and wall thicknesses, providing you with a clear understanding of what you are purchasing. With our extensive selection, you can find the perfect fit for your project, knowing that each product is engineered to meet the highest industry standards. Trust in our expertise, and let us provide the perfect dimensions for your success.

Outside Diameter		API Casing List-Thickness
inch	mm	mm
4 1/2	114.3	5.21	5.69	6.35	7.37	8.56	–	–	–	–	–	–	–	–
5	127.0	5.59	6.43	7.52	9.19	11.10	12.14	12.70	–	–	–	–	–	–
5 1/2	139.7	6.20	6.98	7.72	9.17	10.54	12.70	14.27	15.88	17.45	19.05	20.62	22.22	–
6 5/8	168.3	7.32	8.94	10.59	12.06	–	–	–	–	–	–	–	–	–
7	177.8	5.87	6.91	8.05	9.19	10.36	11.51	12.65	13.72	15.88	17.45	19.05	20.62	22.22
7 5/8	193.7	7.62	8.33	9.52	10.92	12.70	14.27	15.11	15.88	17.45	19.05	–	–	–
7 3/4	196.9	15.11	–	–	–	–	–	–	–	–	–	–	–	–
8 5/8	219.1	6.71	7.72	8.94	10.16	11.43	12.70	14.15	–	–	–	–	–	–
9 5/8	244.5	7.92	8.94	10.03	11.05	11.99	13.84	15.11	15.47	17.07	18.64	20.24	–	–
10 3/4	273.1	7.09	8.89	10.16	11.43	12.57	13.84	15.11	17.07	18.64	20.24	–	–	–
11 3/4	298.5	8.46	9.53	11.05	12.42	13.56	14.78	–	–	–	–	–	–	–
13 3/8	339.7	8.38	9.65	10.92	12.19	13.06	–	–	–	–	–	–	–	–
16	406.4	9.53	11.13	12.57	16.68	–	–	–	–	–	–	–	–	–
18 5/8	473	11.05	–	–	–	–	–	–	–	–	–	–	–	–
20	508	11.13	12.70	16.13	–	–	–	–	–	–	–	–	–	–

Chemical Requirement

We at UNIASEN understand the importance of chemical composition in steel pipes. Our API 5CT Casing and Tubing are manufactured with a specific chemical requirement that ensures durability, corrosion resistance, and high performance. By choosing our products, you are investing in materials that have been meticulously crafted to meet stringent industry standards. Our commitment to quality ensures that you receive products that not only meet but exceed your expectations.

Chemical Composition, Mass Fraction (%)

Grade

Type

min

max

min

max

min

max

min

max

3 4

H40

–

0.030 0.45

–

J55

–

0.030 0.45

–

K55

–

0.030 0.45

–

N80

–

0.030

0.030 0.45

–

N80

–

0.030

0.030 0.45

–

R95

–

0.45c

–

1.9

–

0.030

0.030 0.45

0.45

L80

–

0.43a

–

1.9

–

0.25 0.35

0.35

0.030

0.030 0.45

0.45

L80

9Cr

–

0.15

0.30

0.60

0.90

1.10

8.00

10.0

0.50 0.25

0.25

0.020

0.030 0.45

1.00

L80

13Cr

0.15

0.22

0.25

1.00

–

12.0

14.0

0.50 0.25

0.25

0.020

0.030 0.45

1.00

C90

–

0.35

–

1.20

0.25b

0.85

–

1.50

0.99

–

0.020

0.030 0.45

–

T95

–

0.35

–

1.20

0.25b

0.85

0.40

1.50

0.99

–

0.020

0.030 0.45

–

C110

–

0.35

–

1.20

0.25

1.00

0.40

1.50

0.99

–

0.020

0.030 0.45

–

P110

–

0.030e

–

Q125

–

0.35

1.35

–

0.85

–

1.50

0.99

–

0.020

0.010

–

NOTE Elements shown shall be repored in product analysis.

a   The carbon content for L80 may be increased up to 0.50 % maximum if the product is oil-quenched or polymer-quenched.
b   The molybdenum content for Grade C90 Type 1 has no minimum tolerance if the wall thickness is less than 17.78 mm.
c  The carbon content for R95 may be increased up to 0.55 % maximum if the product is oil-quenched.
d   The molybdenum content for T95 Type 1 may be decreased to 0.15 % minimum if the wall thickness is less than 17.78 mm.
d   For EW Grade P110, the phosphorus content shall be 0.020% maximum and the sulfur content 0.010% maximum.

Chemical Composition for PSL 2 Pipe with t ≤ 25.0 mm (0.984 in.)

Steel Grade (Steel Name)	Mass Fraction, Based on Heat and Product Analyses % max									Carbon Equivalent a % max
Steel Grade (Steel Name)	C b	Si	Mn b	P	S	V	Nb	Ti	Other	CE IIW	CE Pcm
Seamless and Welded Pipe
L245R or BR	0.24	0.40	1.20	0.025	0.015	c	c	0.04	e,l	0.43	0.25
L290R or X42R	0.24	0.40	1.20	0.025	0.015	0.06	0.05	0.04	e,l	0.43	0.25
L245N or BN	0.24	0.40	1.20	0.025	0.015	c	c	0.04	e,l	0.43	0.25
L290N or X42N	0.24	0.40	1.20	0.025	0.015	0.06	0.05	0.04	e,l	0.43	0.25
L320N or X46N	0.24	0.40	1.40	0.025	0.015	0.07	0.05	0.04	d,e,l	0.43	0.25
L360N or X52N	0.24	0.45	1.40	0.025	0.015	0.10	0.05	0.04	d,e,l	0.43	0.25
L390N or X56N	0.24	0.45	1.40	0.025	0.015	0.10 f	0.05	0.04	d,e,l	0.43	0.25
L415N or X60N	0.24 f	0.45 f	1.40 f	0.025	0.015	0.10 f	0.05 f	0.04 f	g,h,l	As agreed
L245Q or BQ	0.18	0.45	1.40	0.025	0.015	0.05	0.05	0.04	e,l	0.43	0.25
L290Q or X42Q	0.18	0.45	1.40	0.025	0.015	0.05	0.05	0.04	e,l	0.43	0.25
L320Q or X46Q	0.18	0.45	1.40	0.025	0.015	0.05	0.05	0.04	e,l	0.43	0.25
L360Q or X52Q	0.18	0.45	1.50	0.025	0.015	0.05	0.05	0.04	e,l	0.43	0.25
L390Q or X56Q	0.18	0.45	1.50	0.025	0.015	0.07	0.05	0.04	d,e,l	0.43	0.25
L415Q or X60Q	0.18 f	0.45 f	1.70 f	0.025	0.015	g	g	g	h,l	0.43	0.25
L450Q or X65Q	0.18 f	0.45 f	1.70 f	0.025	0.015	g	g	g	h,l	0.43	0.25
L485Q or X70Q	0.18 f	0.45 f	1.80 f	0.025	0.015	g	g	g	h,l	0.43	0.25
L555Q or X80Q	0.18 f	0.45 f	1.90 f	0.025	0.015	g	g	g	i,j	As agreed
L625Q or X90Q	0.16 f	0.45 f	1.90	0.02	0.010	g	g	g	j,k	As agreed
L690Q or X100Q	0.16 f	0.45 f	1.90	0.02	0.010	g	g	g	j,k	As agreed
Welded Pipe
L245M or BM	0.22	0.45	1.20	0.025	0.015	0.05	0.05	0.04	e,l	0.43	0.25
L290M or X42M	0.22	0.45	1.30	0.025	0.015	0.05	0.05	0.04	e,l	0.43	0.25
L320M or X46M	0.22	0.45	1.30	0.025	0.015	0.05	0.05	0.04	e,l	0.43	0.25
L360M or X52M	0.22	0.45	1.40	0.025	0.015	d	d	d	e,l	0.43	0.25
L390M or X56M	0.22	0.45	1.40	0.025	0.015	d	d	d	e,l	0.43	0.25
L415M or X60M	0.12 f	0.45 f	1.60 f	0.025	0.015	g	g	g	h,l	0.43	0.25
L450M or X65M	0.12 f	0.45 f	1.60 f	0.025	0.015	g	g	g	h,l	0.43	0.25
L485M or X70M	0.12 f	0.45 f	1.70 f	0.025	0.015	g	g	g	h,l	0.43	0.25
L555M or X80M	0.12 f	0.45 f	1.85 f	0.025	0.015	g	g	g	i,l	0.43 f	0.25
L625M or X90M	0.10	0.55 f	2.10 f	0.02	0.010	g	g	g	i,l	―	0.25
L690M or X100M	0.10	0.55 f	2.10 f	0.02	0.010	g	g	g	i,j		0.25
L830M or X120M	0.10	0.55 f	2.10 f	0.02	0.010	g	g	g	i,j		0.25
a Based on product analysis, for seamless pipe with t > 20.0 mm (0.787 in.), the CE limits shall be as agreed; the CEIIW limits apply if C > 0.12 % and the CEPcm limits apply if C ≤ 0.12 %. b For each reduction of 0.01 % below the specified maximum for C, an increase of 0.05 % above the specified maximum for Mn is permissible, up to a maximum of 1.65 % for grades ≥ L245 or B, but ≤ L360 or X52; up to a maximum of 1.75 % for grades > L360 or X52, but < L485 or X70; up to a maximum of 2.00 % for grades ≥ L485 or X70, but ≤ L555 or X80; and up to a maximum of 2.20 % for grades > L555 or X80. c Unless otherwise agreed, Nb + V ≤ 0.06 %. d Nb + V + Ti ≤ 0.15 %. e Unless otherwise agreed, Cu ≤ 0.50 %; Ni ≤ 0.30 %; Cr ≤ 0.30 % and Mo ≤ 0.15 %. f Unless otherwise agreed. g Unless otherwise agreed, Nb + V + Ti ≤ 0.15 %. h Unless otherwise agreed, Cu ≤ 0.50 %; Ni ≤ 0.50 %; Cr ≤ 0.50 % and Mo ≤ 0.50 %. i Unless otherwise agreed, Cu ≤ 0.50 %; Ni ≤ 1.00 %; Cr ≤ 0.50 % and Mo ≤ 0.50 %. j B ≤ 0.004 %. k Unless otherwise agreed, Cu ≤ 0.50 %; Ni ≤ 1.00 %; Cr ≤ 0.55 % and Mo ≤ 0.80 %. l For PSL 2 pipe grades except those grades to which footnote j) already applies, the following applies: unless otherwise agreed no intentional addition of B is permitted and residual B ≤ 0.001 %.

Mechanical Requirement

Mechanical integrity is at the core of our API 5CT Casing and Tubing. UNIASEN’s products are engineered to meet specific mechanical requirements, providing robustness, resilience, and long-lasting performance. Whether it’s tensile strength, yield strength, or hardness, our products are designed to withstand the challenges of the most demanding environments. Choose UNIASEN, and benefit from steel pipes that perform when it matters most.

Tensile and Hardness Requirements
Grade	Type	Total Elongation Under Load	Yield strength MPa		Tensile strength MPa	Hardness a,c max		Specified Wall Thickness	Allowable Hardness Variation b
Grade	Type	Total Elongation Under Load	min	max	min	HRC	HBW	mm	HRC
1	2	3	4	5	6	7	8	9	10
H40	–	0.5	276	552	414	–	–	–
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	–	–	–
R95	–	0.5	655	758	724	–	–	–
L80	1	0.5	552	655	655	23.0	241	–
L80	9Cr	0.5	552	655	655	23.0	241	–
L80	13Cr	0.5	552	655	655	23.0	241	–
C90	1	0.5	621	724	689	25.4	255	≤12.70 12.71 to 19.04 19.05 to 25.39 ≥25.40	3.0 4.0 5.0 6.0
T95	1	0.5	655	758	724	25.4	255	≤12.70 12.71 to 19.04 19.05 to 25.39 ≥25.40	3.0 4.0 5.0 6.0
C110	–	0.7	758	828	793	30.0	286	≤12.70 12.71 to 19.04 19.05 to 25.39 ≥25.40	3.0 4.0 5.0 6.0
P110	–	0.6	758	965	862	–	–	–	–
Q125	1	0.65	862	1034	931	b	–	≤12.70 12.71 to 19.04 19.05	3.0 4.0 5.0
a In case of dispute, laboratory Rockwell C hardness testing shall be used as the referee method. b No hardness limits, but the maximum variation is restricted as a manufacturing control in accordance with 7.8 and 7.9. c For through-wall hardness tests of Grades L80(all types), C90, T98 and C110, the requirements stated in HRC scale are for maximum mean hardness number.

Steel Grades

UNIASEN offers a wide range of steel grades for API 5CT Casing and Tubing, including H40, J55, K55, N80 all types, L80 all types, C90, R95, T95, P110, C110, and Q125. Each grade is carefully selected to provide specific benefits, ensuring that you receive the optimal product for your application. By choosing our steel grades, you are investing in quality, reliability, and performance, tailored to your unique needs.

Production Tolerance

Precision and consistency are paramount in our production process. UNIASEN’s API 5CT Casing and Tubing are manufactured with strict production tolerances that ensure accuracy and uniformity. From dimensions to weight, we adhere to international standards, providing you with products that you can trust. Our commitment to excellence means that you receive steel pipes that are crafted to perfection, ensuring that your project’s success is built on a foundation of quality and precision.