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.
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
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