OCTG PIPE-OCTG CASING AND TUBING size chart

OCTG (Oil Country Tubular Goods) casing and tubing are highly popular categories of steel pipes among TUSPIPE’s product offerings. TUSPIPE not only ensures the highest quality for the OCTG tubular products it supplies but also has obtained certifications from international safety standards such as API 5CT.

OCTG Meaning

OCTG, or oil country tubular goods, refers to a variety of steel products that are used in the drilling and extraction of oil and gas. Including tubing, casing, and couplings. OCTG products are essential for the safe and efficient operation of oil and gas wells.

The API 5CT is the core standard for OCTG, this standard helps to ensure that OCTG products meet the highest standards of quality and safety. It includes requirements for material quality, dimensions, strength, threading, and testing. In addition to this, there are ISO standards, EN standards (developed by the European Organization for Standardization), non-standard for special environments, and so on. Safeguarding the safety and standards of OCTG piping systems, standardizing production and installation.

OCTG SPECIFICATION

OCTG Pipe Type

Casing: Used to reinforce the well wall, prevent wall collapse, and isolate different formations to ensure drilling safety. It is the basic structure of oil wells and is divided into surface casing, technical casing and oil casing.
Tubing: Used to transport oil and gas from the bottom of the well to the surface. It is usually inside the casing and must have the performance of corrosion resistance and high pressure resistance.
Drill pipe: It is the core tool for drilling wells, and needs to have high strength, abrasion resistance and anti-fatigue performance.

Casing, tubing and drill pipe together constitute the complete structure of the well. The drill pipe completes the drilling task, the casing ensures the stability of the well wall, and the tubing realizes the transportation of oil and gas.

Features of OCTG

High strength and pressure resistance
The extraction process of oil wells will be subject to high pressure and impact, and the extraction time is long, so the related pipes must have pressure resistance to withstand the pressure of the ground, and the extraction intensity is high, the pipe needs to be more durable.
Corrosion resistance
OCTG pipes need to be stable in environments containing corrosive media such as hydrogen sulfide and carbon dioxide to ensure the safety of the piping system.
Sealing
OCTG pipes need to be precisely processed to ensure dimensional accuracy and connection sealing, and threaded connections can be used for greater convenience.
Versatility
OCTG tubing includes casing, tubing and drill pipe, each of which has its own role to play.

Production Standards of OCTG

API 5CT is the American Petroleum Institute’s specification for oil and gaswell casing and tubing. The specification covers coupling, threading, dimensions and other mechanical properties for oil and gas industry products like casing and tubing. API 5CT is the most common standard used in oil and gas industry applications. The specification covers several grades of steel, including J55, K55, N80, L80 and P110. Coupling is a threaded connection used to join oil and gas well casing or tubing. Threading refers to the process of cuttinng threads into the end of a pipe or coupling. Dimensions vary depending on the type of casing or tubing being used. American Petroleum Institute standards are voluntary consensus standards that are not mandated by law. However, oil and gas companies often require that products used in their operations meet API standards.

Below is the OCTG pipe sizing chart, based on API 5CT standard, which contains casing, tubing sizes, chemical properties, physical properties, and more. Related questions can consult us!

Dimensions of OCTG pipe size Chart (Tubing and Casing)

- Specification & Size of OCTG( API Tubing Size Chart)

DN	O. D.		Weight		W. T.		End Processing
			Non-upset	Upset			Steel Grade
			coupling-thread	coupling-thread			Steel Grade
	Inch	mm	lb./ft.	lb./ft.	Inch	mm	H40	J55	L80	N80	C90	T95	P110
2 3/8	2.375	60.32	4	–	0.167	4.24	PU	PN	PN	PN	PN	PN	–
			4.6	4.7	0.19	4.83	PNU	PNU	PNU	PNU	PNU	PNU	PNU
			5.8	5.95	0.254	6.45	–	–	PNU	PNU	PNU	PNU	PNU
			6.6	–	0.295	7.49	–	–	P	–	P	P	–
			7.35	7.45	0.336	8.53	–	–	PU	–	PU	PU	–
2 7/8	2.875	73.02	6.4	6.5	0.217	5.51	PNU	PNU	–	–	–	–	–
			7.8	7.9	0.276	7.01	–	–	–	–	–	–	–
			8.6	8.7	0.308	7.82	–	–	PLB	PLB	PLBE	–	PLB
			9.35	9.45	0.34	8.64	–	–	PLB	PLB	PLBE	–	PLB
			10.5	–	0.392	9.96	–	–	PLB	PLB	PLB	–	PLB
			11.5	–	0.44	11.18	–	–	–	–	PLB	–
3 1/2	3.5	88.9	7.7	–	0.216	5.49	PN	PN	PN	PN	PN	PN	–
			9.2	9.3	0.254	6.45	PNU	PNU	PNU	PNU	PNU	PNU	PNU
			10.2	–	0.289	7.34	PN	PN	PN	PN	PN	PN	–
			12.7	12.95	0.375	9.52	–	–	PNU	PNU	PNU	PNU	PNU
			14.3	–	0.43	10.92	–	–	P	–	P	P	–
			15.5	–	0.476	12.09	–	–	P	–	P	P	–
			17	–	0.53	13.46	–	–	P	–	P	P	–
4	4	101.6	9.5	–	0.226	5.74	PN	PN	PN	PN	PN	PN	–
			–	11	0.262	6.65	PU	PU	PU	PU	PU	PU	–
			13.2	–	0.33	8.38	–	–	P	–	P	P	–
			16.1	–	0.415	10.54	–	–	P	–	P	P	–
			18.9	–	0.5	12.7	–	–	P	–	P	P	–
			22.2	–	0.61	15.49	–	–	P	–	P	P	–
4 1/2	4.5	114.3	12.6	12.75	0.271	6.88	PNU	PNU	PNU	PNU	PNU	PNU	–
			15.2	–	0.337	8.56	–	–	P	–	P	P	–
			17	–	0.38	9.65	–	–	P	–	P	P	–
			18.9	–	0.43	10.92	–	–	P	–	P	P	PLB
			21.5	–	0.5	12.7	–	–	P	–	P	P	PLB
			23.7	–	0.56	14.22	–	–	P	–	P	P	PLB
			26.1	–	0.63	16	–	–	P	–	P	P	PLB
P——Plain；N—— Non-upset coupling-thread；U—— Upset coupling-thread； L——Integral

- Specification & Size of OCTG Steel (API Casing Pipe Size Chart)

DN	O. D.		Weight		W. T.		End Machining Form
	O. D.		Weight		W. T.		Steel Grade
	Inch	mm	lb/ft	kg/m	Inch	mm	H40	J55	L80	N80	C90	P110
	Inch	mm	lb/ft	kg/m	Inch	mm	H40	K55	L80	N80	T95	P110
4 1/2	4.5	114.3	9.5	14.14	0.205	5.21	PS	PS	–	–	–	–
			10.5	15.63	0.224	5.69	–	PSB	–	–	–	–
			11.6	17.26	0.25	6.35	–	PSLB	PLB	PLB	PLB	PLB
			13.5	20.09	0.29	7.37	–	–	PLB	PLB	PLB	PLB
			15.1	22.47	0.337	9.56	–	–	–	–	–	PLB
5	5	127	11.5	17.11	0.22	5.59	–	PS	–	–	–	–
			13	19.35	0.253	6.43	–	PSLB	–	–	–	–
			15	22.32	0.296	7.52	–	PSLB	PLB	PLB	PLBE	PLB
			18	26.79	0.362	9.19	–	–	PLB	PLB	PLBE	PLB
			21.4	31.85	0.437	11.1	–	–	PLB	PLB	PLB	PLB
			23.2	34.53	0.478	12.14	–	–	–	–	PLB	–
			24.1	35.86	0.5	12.7	–	–	–	–	PLB	–
5 1/2	5.5	139.7	14	20.83	0.244	6.2	PS	PS	–	–	–	–
			15.5	23.07	0.275	6.98	–	PSLB	–	–	–	–
			17	25.3	0.304	7.72	–	PSLB	PLB	PLB	PLBE	PLB
			20	29.76	0.361	9.17	–	–	PLB	PLB	PLBE	PLB
			23	34.23	0.415	10.54	–	–	PLB	PLB	PLBE	PLB
			26.8	39.88	0.5	12.7	–	–	–	–	–	–
			29.7	44.2	0.562	14.27	–	–	–	–	–	–
			32.6	48.51	0.625	15.88	–	–	–	–	–	–
			35.3	52.53	0.687	17.45	–	–	–	–	–	–
			38	56.55	0.75	19.05	–	–	–	–	–	–
			40.5	60.27	0.812	20.62	–	–	–	–	–	–
			43.1	64.14	0.875	22.22	–	–	–	–	–	–
6 5/8	6.625	168.28	20	29.76	0.288	7.32	PS	PSLB	–	–	–	–
			24	35.72	0.352	8.94	–	PSLB	PLB	PLB	PLBE	PLB
			28	41.67	0.417	10.59	–	–	PLB	PLB	PLBE	PLB
			32	47.62	0.475	12.06	–	–	PLB	PLB	PLBE	PLB
7	7	177.8	17	25.3	0.231	5.87	PS	–	–	–	–	–
			20	29.76	0.272	6.91	PS	PS	–	–	–	–
			23	34.23	0.317	8.05	–	PSLB	PLB	PLB	PLBE	–
			26	38.69	0.362	9.19	–	PSLB	PLB	PLB	PLBE	PLB
			29	43.16	0.408	10.36	–	–	PLB	PLB	PLBE	PLB
			32	47.62	0.453	11.51	–	–	PLB	PLB	PLBE	PLB
			35	52.09	0.498	12.65	–	–	PLB	PLB	PLBE	PLB
			38	56.55	0.54	13.72	–	–	PLB	PLB	PLBE	PLB
			42.7	63.54	0.625	15.88	–	–	–	–	–	–
			46.4	69.05	0.687	17.45	–	–	–	–	–	–
			50.1	74.56	0.75	19.05	–	–	–	–	–	–
			53.6	79.77	0.812	20.62	–	–	–	–	–	–
			57.1	84.97	0.875	22.22	–	–	–	–	–	–
7 5/8	7.625	193.68	24	35.72	0.3	7.62	PS	–	–	–	–	–
			26.4	39.29	0.328	8.33	–	PSLB	PLB	PLB	PLBE	PLB
			29.7	44.2	0.375	9.52	–	–	PLB	PLB	PLBE	PLB
			33.7	50.15	0.43	10.92	–	–	PLB	PLB	PLBE	PLB
			39	58.05	0.5	12.7	–	–	PLB	PLB	PLBE	PLB
			42.8	63.69	0.562	14.27	–	–	PLB	PLB	PLB	PLB
			45.3	67.41	0.595	15.11	–	–	PLB	PLB	PLB	PLB
			47.1	70.09	0.625	15.88	–	–	PLB	PLB	PLB	PLB
			51.2	76.19	0.687	17.45	–	–	–	–	–	–
			55.3	80.3	0.75	19.05	–	–	–	–	–	–
8 5/8	8.625	219.08	24	35.72	0.264	6.71	–	PS	–	–	–	–
			28	41.62	0.304	7.72	PS	–	–	–	–	–
			32	47.62	0.352	8.94	PS	PSLB	–	–	–	–
			36	53.57	0.4	10.16	–	PSLB	PLB	PLB	PLBE	PLB
			40	59.53	0.45	11.43	–	–	PLB	PLB	PLBE	PLB
			44	65.48	0.5	12.7	–	–	PLB	PLB	PLBE	PLB
			49	72.92	0.557	14.15	–	–	PLB	PLB	PLBE	PLB
9 5/8	9.625	244.48	32.3	48.07	0.312	7.92	PS	–	–	–	–	–
			36	53.57	0.352	8.94	PS	PSLB	–	–	–	–
			40	59.53	0.395	10.03	–	PSLB	PLB	PLB	PLBE	–
			43.5	64.73	0.435	11.05	–	–	PLB	PLB	PLBE	PLB
			47	69.94	0.472	11.99	–	–	PLB	PLB	PLBE	PLB
			53.5	79.62	0.545	13.84	–	–	PLB	PLB	PLBE	PLB
			58.4	86.91	0.595	15.11	–	–	PLB	PLB	PLB	PLB
			59.4	88.4	0.609	15.47	–	–	–	–	–	–
			64.9	96.58	0.672	17.07	–	–	–	–	–	–
			70.3	104.62	0.734	18.64	–	–	–	–	–	–
			75.6	112.5	0.797	20.24	–	–	–	–	–	–
10 3/4	10.75	273.05	32.75	48.74	0.279	7.09	PS	–	–	–	–	–
			40.5	60.27	0.35	8.89	PS	PSB	–	–	–	–
			15.5	67.71	0.4	10.16	–	PSB	–	–	–	–
			51	75.9	0.45	11.43	–	PSB	PSB	PSB	PSBE	PSB
			55.5	82.59	0.495	12.57	–	–	PSB	PSB	PSBE	PSB
			60.7	90.33	0.545	13.84	–	–	–	–	PSBE	PSB
			65.7	97.77	0.595	15.11	–	–	–	–	PSB	PSB
			73.2	108.93	0.672	17.07	–	–	–	–	–	–
			79.2	117.86	0.734	18.64	–	–	–	–	–	–
			85.3	126.94	0.797	20.24	–	–	–	–	–	–
11 3/4	11.75	298.45	42	62.5	0.333	8.46	PS	–	–	–	–	–
			47	69.94	0.375	20.24	–	–	–	–	–	–
			54	80.36	0.435	8.46	–	–	–	–	–	–
			60	89.29	0.489	9.53	–	–	–	–	–	–
			65	96.73	0.534	11.05	–	–	–	–	–	–
			71	105.66	0.582	14.42	–	–	–	–	–	–
13 3/8	13.375	339.73	48	71.43	0.33	8.38	PS	–	–	–	–	–
			54.5	81.1	0.38	9.65	–	PSB	–	–	–	–
			61	90.78	0.43	10.92	–	PSB	–	–	–	–
			68	101.19	0.48	12.19	–	PSB	PSB	PSB	PSB	PSB
			72	107.15	0.514	13.06	–	–	PSB	PSB	PSB	PSB
16	16	406.4	65	96.73	0.375	9.53	PS	–	–	–	–	–
			75	111.61	0.438	11.13	–	PSB	–	–	–	–
			84	125.01	0.495	12.57	–	PSB	–	–	–	–
			109	162.21	0.656	16.66	–	P	P	P	–	P
18 5/8	18.625	473.08	87.5	130.21	0.435	11.05	PS	PSB	–	–	–	–
20	20	508	94	139.89	0.438	11.13	PSL	PSLB	–	–	–	–
			106.5	158.49	0.5	12.7	–	PSLB	–	–	–	–
			133	197.93	0.635	16.13	–	PSLB	–	–	–	–
P——Plain；S——Short-thread；L——Long-thread；B——Buttress thread；E——Extreme thread

Chemical Composition of OCTG

Group	Steel	Type	C		Mn		Mo		Cr		Ni	Cu	P	S	Si
Group	Grade	Type	min.	max.	min.	max.	min.	max.	min.	max.	min.	max.	max.	max.	max.
1	H40	–	–	–	–	–	–	–	–	–	–	–	0.03	0.03	–
	J55	–	–	–	–	–	–	–	–	–	–	–	0.03	0.03	–
	K55	–	–	–	–	–	–	–	–	–	–	–	0.03	0.03	–
	N80	1	–	–	–	–	–	–	–	–	–	–	0.03	0.03	–
	N80	Q	–	–	–	–	–	–	–	–	–	–	0.03	0.03	–
2	M65	–	–	–	–	–	–	–	–	–	–	–	0.03	0.03	–
	L80	1	–	0.43	–	1.9	–	–	–	–	0.25	0.35	0.03	0.03	0.5
		9Cr	–	0.15	0.3	0.6	0.9	1.1	8	10	0.5	0.25	0.02	0.01	1
		13Cr	0.15	0.22	0.25	1	–	–	12	14	0.5	0.25	0.02	0.01	1
	C90	1	–	0.35	–	1.2	0.25	0.85	–	1.5	0.99	–	0.02	0.01	–
	C90	2	–	0.5	–	1.9	–	NL	–	NL	0.99	–	0.03	0.01	–
	C95	–	–	0.45	–	1.9	–	–	–	–	–	–	0.03	0.03	0.5
	T95	1	–	0.35	–	1.2	0.25	0.85	0.4	1.5	0.99	–	0.02	0.01	–
	T95	2	–	0.5	–	1.9	–	–	–	–	0.99	–	0.03	0.01	–
3	P110	–	–	–	–	–	–	–	–	–	–	–	0.03	0.03	–
4	Q125	1	–	0.35	–	1.35	–	0.85	–	1.5	0.99	–	0.02	0.01	–
		2	–	0.35	–	1	–	NL	–	NL	0.99	–	0.02	0.02	–
		3	–	0.5	–	1.9	–	NL	–	NL	0.99	–	0.03	0.01	–
		4	–	0.5	–	1.9	–	NL	–	NL	0.99	–	0.03	0.02	–
a. The carbon content for L80 may be increased up to 0, 50 % maximum if the product is oil-quenched.
b. The molybdenum content for Grade C90 Type 1 has no minimum tolerance if the WT 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 WT is less than 17, 78 mm.
e. For EW Grade P110, the phosphorus content shall be 0,020 % maximum and the sulfur content 0,010 % maximum
NL = no limit. Elements shown shall be reported in product analysis.

Mechanical Properties of OCTG pipe chart

Grade	Type	Total Elongation Under Load	Yield strength MPa		Tensile strength MPa	Hardness a,c max		Specified Wall Thickness	Allowable Hardness Variation b
Tensile and Hardness Requirements
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.

What Is OCTG--Types of OCTG products

OCTG stands for Petroleum State Pipe. It is a family of rolled metal products used in oil and gas drilling and production operations. The term OCTG is used in a wide range of products, including drill pipe, casing and tubing. These products are used to connect wellheads and downhole equipment to extract oil and gas from the surface. OCTG plays an important role in the oil and gas industry, and its products have great significance for safe and efficient drilling operations.

Drill Pipe

Drill pipe is a type of steel pipe used in oil and gas Wells. It consists of several different parts, including kelly, drill bit, drill string and casing. The kelly pipe is attached to the rig, it helps to rotate the drill string, it is part of the drill pipe. The drill bit is the part of the drill pipe that is drilled into the rock and is generally made of steel or tungsten. The drill string consists of drill pipe and extends from the kelly pipe to the drill bit, which helps to provide support for the bit as it is drilled. Casing is the end of the drill pipe and helps prevent the well from collapsing. All of these components work together to help oil and gas Wells run properly.

Casing Pipe

Casing and tubing are necessary in the process of oil drilling. Casing is placed and wrapped around the wellbore before drilling begins. The purpose is to protect soil layers and groundwater from contamination by drilling mud and/or fracturing fluids. In addition, casing stabilizes the wellbore. Drilling and casing operations alternate — the drill string is removed at predetermined intervals and the wellbore is lined and cemented with casing.

Tubing

Tubing is used to carry oil from deep inside an oil well to the surface. This is the third stage of the wellbore process. Oil and gas occasionally rise to the surface on their own; However, pumps are usually required to bring the fluid to the surface. Tubing is usually smaller in diameter than casing, except for those with a diameter of 4 1/2 inches. Therefore, the tubing must be secured to an external support structure, such as a rig or platform, to prevent collapse due to differential pressure.

Types of OCTG Connections

Oil Country Tubular Goods (OCTG) is a type of steel pipe used to transport crude oil, natural gas and other fluids in the oil and gas industry. It consists of metal attachments and steel pipes, which come in different sizes and grades, and each length of pipe has a special function and purpose. The purpose of the OCTG connection is to connect these steel pipelines together in series to build a network that can transport oil and gas from one location to another.

API Connection
API connection is a type of connection widely used in the oil and gas industry. They meet and exceed all of the American Petroleum Institute’s (API) regulatory standards. The API defines two types of coupling: one is undisturbed coupling (NU) and the other is externally disturbed coupling (EU). The NU connection is designed to connect two pipes of the same diameter, while the EU connection is designed to connect two pipes of different diameters.

Advanced connectivity
Advanced connectivity is a special type of proprietary connection that provides advanced features that API connectivity does not. Most advanced connections offer metal-to-metal seals to improve the integrity of high-pressure seals. The advanced connection has the characteristics of straight connection, no slot and special gap. This connection is suitable for gas Wells, high-pressure Wells, and Wells prone to corrosive wastewater production.

Furthermore, OCTG threading technology is a process method for forming grooves in the casing body and end.

It can form a seal with these grooves when the pipe is connected to another device or pipe. Threads are generally leak-proof and robust enough to withstand oil and gas distribution grids. There are three different types of OCTG casing, each with its own unique advantages: for example, short round thread casing (STC), long Round thread casing (LTC), and support thread casing (BTC).

STC is considered the preferred solution for short length casing applications that do not involve high axial loads or bending. LTC is particularly suitable for axial loads, except in the case of extreme temperature or pressure overall well conditions. BTC is an excellent connection that provides long life in the face of high axial loads, moderate internal pressures and temperatures. Both the STC and LTC are round threads of a non-runout design with 8 dome threads per inch. The BTC has a flat root and flat top square thread, a runout design, and is equipped with five support threads per inch.

Each type of OCTG thread has different advantages and performance, which also makes OCTG the best choice for some applications. When choosing the best type of threading for your project, be sure to consider the well condition and the type of equipment that will be used.

OCTG for Sand Control - Slotted Liner

Slotted liner is a well screening device that is used for sand control and fluid retention in petroleum wells. It consists of a series of slotted holes that are drilled into the well screen to allow fluid to flow through while retaining sand and other particulate matter. Slotted liner is an effective way to improve well productivity and prevent formation damage. It is also a cost-effective alternative to traditional well screens. Slotted liner can be used in both new and existing wells, and it is available in a variety of materials and configurations.

Why Choose TUSPIPE?

Since 1998, Tianjin United Steel Piping Co., Ltd (TUSPIPE) has been committed to supplying high-quality line pipes.

With over 500,000 tons annual production capacity, the company serves various fields and industries, such as oil & gas exploitation and transmission, ship & auto-building, water & electricity, environmental protection, mechanical engineering, infrastructure construction and etc.

TUSPIPE places a premium on product quality and rigorous product quality control. In order to maintain good product quality, the company has established a Test & Inspection Center since 2004. With a series of state-of-the-art tests and inspection equipment, the test & inspection center is able to perform the tensile tests, hydro tests, impact tests, DWTT, etc.