Duplex Stainless Pipe and Pipe Fittings

Duplex stainless steel pipes and pipe fittings have become increasingly popular in recent years due to their superior strength and corrosion resistance properties. These pipes are made up of a combination of austenitic and ferritic stainless steels, which results in a material that is stronger than traditional stainless steel pipes. One of the main advantages of duplex pipes and pipe fittings is its ability to withstand harsh environments such as those found in the oil and gas industry. The seamless duplex piping is particularly useful for applications where there is a need for high pressure or high-temperature resistance.

In addition to its strength, duplex stainless steel pipe and pipe fittings also offers excellent resistance to corrosion caused by chemicals and saltwater. This makes it an ideal choice for use in marine applications such as shipbuilding and offshore drilling platforms. The ASTM A312 standard governs the manufacturing process of duplex pipes, ensuring that they meet strict quality standards. These pipes are available in various sizes, shapes, and lengths, making them suitable for a wide range of applications.

At Om Steel, we provide a comprehensive selection of duplex stainless steel pipes and pipe fittings. Our inventory consists of various sizes, schedules, and grades to cater to the diverse requirements of different industries. Whether you need duplex stainless steel pipes for fluid transportation, heat exchangers, or any other specific application, we have the right solution for you.

Duplex stainless steel pipes and pipe fittings are also used extensively in the chemical processing industry due to their excellent resistance to corrosion caused by acids and other chemicals. They can be threaded or welded together with valves to create complex piping systems that can handle even the most demanding industrial processes.

Benefits of Using Duplex Stainless Steel Pipes

Durability

Duplex stainless steel pipes are known for their durability. They can withstand harsh environments and extreme temperatures without losing their structural integrity. This makes them ideal for use in industries such as oil and gas, chemical processing, and marine engineering.

High Strength

Duplex stainless steel has higher strength than austenitic stainless steel due to its two-phase microstructure. This property makes it ideal for use in structural components that require high strength and toughness.

Corrosion Resistance

Another major benefit of duplex stainless steel pipes is their corrosion resistance. They are resistant to both uniform and localized corrosion, making them ideal for use in corrosive environments. This also means that they require less maintenance than other materials.

Strength

Duplex stainless steel pipes have excellent strength properties, including high tensile strength and yield strength. This makes them suitable for use in applications where high pressure or heavy loads are involved.

Typical Specifications for Duplex Steel Piping

ASME SA31

ASME SA312 is a standard specification for seamless and welded austenitic stainless steel pipes used in high-temperature and general corrosive service. This specification covers grades TP304/L/H/N, TP316/L/H/N/Ti, TP321/H, TP347/H, and duplex grades S31803/S32205.

API 6D

API 6D is a specification for pipeline valves used in the petroleum industry. This specification covers both floating ball valves (FBVs) and trunnion-mounted ball valves (TMBVs) made from various materials including duplex stainless steel. The API 6D standard defines requirements for valve design features such as end connections, body styles, pressure ratings, temperature ranges, seat materials, stem seals, actuation options (manual or automated), among others. Additionally, API 6D specifies testing procedures to ensure the quality and performance of these valves under different operating conditions.

Types of Duplex Steel Piping

There are two main types of duplex stainless steels: lean duplex and super duplex. Lean duplex steels have lower amounts of alloying elements such as chromium (~22%) and molybdenum (~3%) compared to super duplex steels. Super duplex steels, on the other hand, contain higher levels of these elements (~25% Cr and ~7% Mo) as well as other elements such as nitrogen and tungsten. The choice between lean duplex and super duplex steel piping depends on the specific application requirements such as corrosion resistance, strength, and cost.

Products

ASTM A789 Duplex Steel Pipes and Pipe Fittings

Specification

Standard Specification	ASTM A790 ASME SA790, F51
Manufacturing Type	Seamless / ERW / Welded / Fabricated / CDW / CDS / DOM / CEW / 100% X Ray Welded
Thickness Range	SCH 5, SCH10, SCH 40, SCH 80, SCH 80S, SCH 160, SCH XXH, SCH XXS, SCH XS
Origin	Europe, USA, South Korea
Standard	SUS, JIS, AISI, ASTM, GB, DIN, EN
Value Added Services	– Cutting – Bevelling – Threading – Destructive and Non Destructive – Ultrasonic Testing – Draw & Expansion as per required Size & Length

Duplex steel Pipe fittings

specifications

Specification	ASTM A 815, ASME SA 815, ASTM A 182, ASME SA 182
Type	Seamless / Welded / Fabricated
Range	1/2 “NB to 24″NB in Sch 10S, 40S, 80S, 160S, XXS
Dimensions	ANSI / ASME B16.9, B16.28, MSS – SP – 43

Duplex stainless steel Pipe

Schedule Chart

1/8″ IPS(.405″ O.D.)	3 1/2″ IPS (4.000″ O.D.)
Seamless Pipes SCH 40, 80	Pipes, SCH 10, 40, 80, 160, XXH
1/4″ IPS(.540″ O.D.)	4″ IPS(4.500″ O.D.)
Pipes, SCH 10, 40, 80	Seamless Pipes, SCH 10, 40, 80, 160, XXH
3/8″ IPS(.675″ O.D.)	5″ IPS(5.563″ O.D.)
Seamless Pipes, SCH 10, 40, 80	Pipes, SCH 10, 40, 80, 160, XXH
1/2″ IPS(.840″ O.D.)	6″ IPS(6.625″ O.D.)
Seamless Pipes, SCH 5, 10, 40, 80, 160, XXH	Seamless Pipes, SCH 5, 10, 40, 80, 120, 160, XXH
3/4″ IPS(1.050″ O.D.)	8″ IPS(8.625″ O.D.)
Pipes, SCH 10, 40, 80, 160, XXH	Stainless Pipes, SCH 5, 10, 40, 80, 120, 160, XXH
1″ IPS(1.315″ O.D.)	10″ IPS(10.750″ O.D.)
Seamless Pipes, SCH 5, 10, 40, 80, 160, XXH	Pipes, SCH 10, 20, 40, 80 (.500), TRUE 80(.500)
1-1/4″ IPS(1.660″ O.D.)	12″ IPS(12.750″ O.D.)
Seamless Pipes, SCH 10, 40, 80, 160, XXH	Pipes, SCH 10, 20, 40(.375), TRUE40(.406), SCH80(.500)
1-1/2″ IPS(1.900″ O.D.)	14″ IPS(14.000″ O.D.)
Seamless Pipes, SCH 10, 40, 80, 160, XXH	Pipes, SCH10 (.188), SCH40 (.375)
2″ IPS(2.375″ O.D.)	16″ IPS(16.000″ O.D.)
Seamless Pipes, SCH 10, 40, 80, 160, XXH	Pipes, SCH10(.188), SCH40(.375)
2 1/2″ IPS(2.875″ O.D.)	18″ IPS (18.000″ O.D.)
Seamless Pipes, SCH 10, 40, 80, 160, XXH	Pipes, SCH-40 (.375)
3″ IPS (3.500″ O.D.)	–
Seamless Pipes, SCH 5, 10, 40, 80, 160, XXH	–

Duplex Stainless Steel Pipe

Weight Chart

OUTSIDE DIA (MM)	WALL THK (MM)	IN.	SCHEDULE	KG/M
13.72	1.65	1/4	10S	0.5
13.72	2.24	1/4	40S	0.64
13.72	3.02	1/4	80S	0.81
17.15	1.65	3/8	10S	0.64
17.15	2.31	3/8	40S	0.86
17.15	3.2	3/8	80S	1.12
21.34	2.11	1/2	10S	1.02
21.34	2.77	1/2	40S	1.29
21.34	3.73	1/2	80S	1.65
26.67	2.11	3/4	10S	1.3
26.67	2.87	3/4	40S	1.71
26.67	3.91	3/4	80S	2.23
33.4	2.77	1	10S	2.13
33.4	3.38	1	40S	2.54
33.4	4.55	1	80S	3.29
33.4	6.352	1	160	4.3
42.16	2.77	1¼	10S	2.73
42.16	3.56	1¼	40S	3.44
42.16	4.85	1¼	80S	4.53
42.16	6.352	1¼	160	5.69
48.26	2.77	1½	10S	3.16
48.26	3.68	1½	40S	4.11
48.26	5.08	1½	80S	5.49
60.33	2.77	2	10S	3.99
60.33	3.91	2	40S	5.52
60.33	5.54	2	80S	7.6
60.33	8.742	2	160	11.29
73.03	3.05	2½	10S	5.35
73.03	5.16	2½	40S	8.77
73.03	7.01	2½	80S	11.59
88.9	3.05	3	10S	6.56
88.9	5.49	3	40S	11.47
88.9	7.62	3	80S	15.51
88.9	11.132	3	160	21.67
101.6	3.05	3½	10S	7.53
101.6	5.74	3½	40S	13.78
101.6	8.08	3½	80S	18.92
114.3	3.05	4	10S	8.5
114.3	6.02	4	40S	16.32
114.3	8.56	4	80S	22.67
114.3	13.492	4	160	34.05
141.3	6.55	5	40S	22.1
141.3	9.53	5	80S	31.44
141.3	15.882	5	160	49.87
168.28	3.4	6	10S	14.04
168.28	7.11	6	40S	28.69
168.28	10.97	6	80S	43.21
168.28	14.27	6	120	54.75
168.28	18.262	6	160	68.59
219.08	8.18	8	40S	43.2
219.08	12.7	8	80S	65.63
219.08	18.23	8	120	91.3
219.08	23.012	8	160	112.97

Duplex Stainless steel Pipes and Pipe Fittings

Chemical Composition

MATERIAL	COMPOSITION % (APPROX)
–	Cr	Ni	Mo	N	Mn	W	Cu
2101 LDX	21.5	1.5	0.3	0.22	S	–	–
DX2202	23	2.5	0.3	0.2	1.5	–	–
RDN 903	20	1.8	0.2	0.11	4.2	–	–
2304	23	4.8	0.3	0.1	–	–	–
2205	22	5.7	3.1	0.17	–	–	–
2507	25	7	4	0.27	–	–	–
Zeron 100	25	7	3.2	0.25	–	0.7	0.7
“Ferrinox 255/ Uranus 2507Cu”	25	6.5	3.5	0.25	–	–	1.5

Application Industry

Serving Diverse Sectors with Precision & Performance

Om Steel supplies premium steel and alloy products to a wide range of industries, ensuring strength, durability, and performance in every application. From construction, oil & gas, and automotive to power plants, shipbuilding, and chemical processing — our materials meet the demands of critical operations. Trusted by industry leaders, we deliver solutions that stand up to the toughest challenges.