Duplex stainless steel pipes are becoming more and more common. Due to its excellent resistance to chloride stress corrosion cracking, high thermal conductivity, and a low coefficient of thermal expansion, duplex stainless steel tubing are being offered by all the major stainless steel mills.
Wuxi Cepheus is one of the leading manufacturers and suppliers of stainless steel products. Duplex stainless pipe is one of the major products in Wuxi Cepheus.
Duplex stainless steel pipe can be divided into two types: seamless and welded stainless steel pipe. Wuxi Cepheus can manufacture stainless steel duplex pipe in S31500, S31803, S32205, S32304, S32520，S32550, S32750, S32760, and others.
Duplex stainless steel pipe are always inventoried in diameter 10mm to 762mm. The wall thickness of duplex stainless tube we produce is 0.5-50mm.
| Specification | |
| Size | OD: 10 ~ 762mm; WT: 0.5 ~ 50mm; Length: 6m, 12m, Max.18m |
| Process | Seamless, Welded |
| Grade | S31500, S31803, S32205, S32304, S32520， S32550, S32750, S32760 |
| Standard | ASTM A789, ASTM A790 |
| Surface | Aid Pickling, Polishing(180#, 220#, 240#, 320#, 400#, 600#) |
| Theoretical Weight(kg/m) | Weight/meter = (OD-WT)*WT*0.02507 Both OD and WT in mm. |
Note:
OD is the specified outside diameter.
WT is the specified wall thickness
Chemical Composition
| UNS | C | Mn | P | S | Si | Ni | Cr | Mo | N | Cu | Others |
| S31500 | 0.030 | 1.20-2.00 | 0.030 | 0.030 | 1.40-2.00 | 4.2-5.2 | 18.0-19.0 | 2.50-3.00 | 0.05-0.10 | … | … |
| S31803 | 0.030 | 2.00 | 0.030 | 0.020 | 1.00 | 4.5-6.5 | 21.0-23.0 | 2.5-3.5 | 0.08-0.20 | … | … |
| S32205 | 0.030 | 2.00 | 0.030 | 0.020 | 1.00 | 4.5-6.5 | 22.0-23.0 | 3.0-3.5 | 0.14-0.20 | … | … |
| S32304 | 0.030 | 2.50 | 0.040 | 0.040 | 1.00 | 3.0-5.5 | 21.5-24.5 | 0.05-0.60 | 0.05-0.20 | 0.05-0.60 | … |
| S32520 | 0.030 | 1.50 | 0.035 | 0.020 | 0.80 | 5.5-8.0 | 24.0-26.0 | 3.0-5.0 | 0.20-0.356 | 0.5-3.00 | … |
| S32550 | 0.04 | 1.50 | 0.040 | 0.030 | 1.00 | 4.5-6.5 | 24.0-27.0 | 2.9-3.9 | 0.10-0.25 | 1.50-2.50 | … |
| S32750 | 0.030 | 1.20 | 0.035 | 0.020 | 0.80 | 6.0-8.0 | 24.0-26.0 | 3.0-5.0 | 0.24-0.32 | 0.5 | … |
| S32760 | 0.05 | 1.00 | 0.030 | 0.010 | 1.00 | 6.0-8.0 | 24.0-26.0 | 3.0-4.0 | 0.20-0.30 | 0.50-1.00 | W0.50-1.00 |
Note A: Maximum, unless a range or minimum is indicated. Where ellipses(…) appear in this table, there is no minimum and analysis for the element need not to be determined or reported.
Tensile and Hardness
| UNS Designation | Tensile Strength, min MPa | Yield Strength, min MPa | Elongation in 50mm min, % | Hardness, Max | |
| HBW | HRC | ||||
| S31500 | 630 | 440 | 30 | 290 | 30 |
| S31803 | 620 | 450 | 25 | 290 | 30 |
| S32205 | 655 | 450 | 25 | 290 | 30 |
| S32304 | 600 | 400 | 25 | 290 | 30 |
| S32520 | 770 | 550 | 25 | 310 | … |
| S32550 | 760 | 550 | 15 | 297 | 31 |
| S32750 | 800 | 550 | 15 | 300 | 32 |
| S32760 | 750 | 550 | 25 | 300 | … |
Tolerances
| Group | Size, Outside Diameter, mm | Tolerances in Outside Diameter, mm | Average Wall Tolerance in Wall Thickness, % | Minimum Wall Tolerances in Wall Thickness, % | Tolerances in Cut Length, mm | Thin Wall Tubes | ||
| Over | Under | Over | Under | |||||
| 1 | Up to 12.7, excl | ±0.13 | ±15 | 30 | 0 | 3 | 0 | … |
| 2 | 12.7 to 38.0, excl | ±0.13 | ±10 | 20 | 0 | 3 | 0 | Less than 1.6mm specified |
| 3 | 38.1 to 88.9, excl | ±0.25 | ±10 | 20 | 0 | 5 | 0 | Less than 2.4mm specified |
| 4 | 88.9 to 139.7, excl | ±0.38 | ±10 | 20 | 0 | 5 | 0 | Less than 3.8mm specified |
| 5 | 139.7 to 203.2, excl | ±0.76 | ±10 | 20 | 0 | 5 | 0 | Less than 3.8mm specified |
Packing Information
Duplex pipes from Wuxi Cepheus are packed according to the customer’s requirement. To avoid any damage which might be caused during international transportation, we provide some optional packaging methods, including woven bags, plywood cases, and wooden boxes.