Duplex Pipe and Super Duplex 2507 Stainless Steel Tubing
SAF 2205 Duplex pipe and SAF 2507 Super duplex pipe are our strength product. Duplex stainless steel is an austenite-ferrite dual phase stainless steel, it is developed for applications that demand high strength and corrosion resistance. Duplex stainless steel pipe is a cost effective solution for many applications where the 300 series stainless steel pipe are susceptible to chloride stress corrosion cracking. Duplex 2205 and 2507 super duplex stainless steel pipe is an idea choice for the applications which require exceptional strength and corrosion resistance, such as chemical process, petrochemical, and seawater equipment. As a professional supplier of duplex pipe in China, we provides high quality duplex 2205 (S31803) pipes and super duplex 2507 (S32750) pipe and tubing according to ASTM A790, ASTM A789, EN 10216-5 etc.
What is Duplex Stainless Steel:
Duplex Stainless Steel (DSS) including grades duplex 2205(S31803) and super duplex, they are commonly consist of 50% ferrite and 50% austenite, and generally requires not less than 30%. Duplex stainless steel has good welding performance and high strength. Compared with austenitic stainless steel, it is about double yield strength of stainless steel 316, 317 etc., it make the equipment lighter and stronger. Duplex stainless steel has very good resistance to localized corrosion and stress corrosion cracking. Duplex steel is not intended to be used at temperatures above 300°C due to embrittlement, the continuous use temperature is from -50 to 250 °C.
Duplex Stainless Steel Grade:
SAF 2205 is the most common grade for duplex stainless steel, ASME/ASTM grade is UNS S32205 or the similar grade S31803 , equivalent to EN/DIN 1.4462.
SAF 2507 is a super duplex steel, the ASTM grade is S32750, equivalent to EN/DIN 1.4410. We can supply duplex pipes and fittings with high quality , mill cost and fast delivery time.
PREN of DSS and SDSS Pipe
What is PREN - Pitting Resistance Equivalent Number, abbreviated as PREN, is a set of algorithms calculated on the basis of the mass fraction of certain elements in the metal. The value is often used in the evaluation method for comparison of pitting corrosion resistance.
There is a formula for PREN calculating:
PREN=Cr%+3.3 *（Mo+0.5W）%+16 *N%
As per ASTM A790, PREN of 22 Cr duplex pipe is >31, and 25 Cr super duplex pipe is more than 40. If you have special requirement, you are welcome to contact us, our factory can accept customized fabrication.
What We Do for Duplex 2205 Pipe:
Our partner factory is mainly focus on the manufacturing of duplex stainless steel pipe, with good experience and reliable quality control system. Nowadays, Kaysuns supplies both duplex stainless steel pipe and super duplex stainless steel pipes and tubes conform to standard ASTM A790, ASTM A789, EN 10216-5 etc.
Super duplex 2507 pipe is a super duplex steel pipe with 25% chromium, 4% molybdenum, and 7% nickel. The common grade of super duplex steel is SAF 5027 (S32750, S32760), they have similar composition and mechanical properties. The high chromium, molybdenum, and nitrogen levels provide excellent resistance to pitting, crevice, and general corrosion. Compared to duplex stainless steel pipe, SAF 2507 super duplex steel pipe is highly resistant to uniform corrosion by organic acids such as formic and acetic acid.
*Super duplex S32760 is not a common grade in China, so we may couldn't offer it with small quantity for pipes and butt-weld fittings. But it is available for forged fittings and flanges.
Manufacturing of DSS and SDSS Pipe
Cold drawn and cold rolled is the mainly process for seamless duplex stainless steel pipe. Due to the material characteristic of high strength and hardness, duplex steel is more difficult to process than austenitic steel. It is very easy to damage, especially for small thickness and large diameter pipes , it has a long and hard-working procedures, that's why the delivery time of duplex pipe is long.
- Supply both seamless and welded.
- 10 years experience for fabrication and supplying.
- Computer temperature controlled heat treatment facility.
- Reliable based material vendor management.
- Testing laboratory of NDT and PMI etc.
- Mill certificate to EN10204 3.1/3.2.
- Non-standard dimension fabrication and fast delivery time.
|Dimension||Welded: 1/2"~72" / 1.2mm~50mm||Seamless: 3/8"~16" / SCH10S, 40S, STD, XS, SCH80S|
|Grade||UNS S31803, S32205, S32750, S32760, S32304, 1.4462, 1.4410, 1.4501, 1.4362 etc.|
|Standard||ASTM A789, ASTM A790, EN10216-5, EN/DIN17455-2, EN17456-2etc.|
Applications of Duplex Stainless Steel Pipes
- Oil and gas industry equipment
- Chemical process industries
- Vessels and ship building
- Offshore platforms
- heat exchangers
- process and service water systems
- fire-fighting systems
- injection and ballast water systems
- Power industry FGD systems
- Utility and industrial scrubber systems, absorber towers, ducting, and piping
- Desalination plants, high pressure RO-plant and seawater piping
- Mechanical and structural components, high strength, corrosion-resistant parts
Stainless Steel Pipes Catalog
|Duplex Steel 2205|
|Super Duplex 2507|
|Stainless Steel Pipe Catalog|
|Dimension of Duplex Stainless Steel Pipes|
|ASTM SA789 -2010|
|ASTM SA790 -2010|
*For more information about duplex/super duplex stainless steel pipe, please contact us.