Duplex stainless seamless pipe
Duplex stainless has
Two phases of metallographic structure of austenite and ferrite.
The physical property indicates the middle of austenite and ferrite.
It is highly seawater-resistant and stain-resistant as well as strong to an impact. Regarding these characteristics, Duplex stainless steel is used as a seawater condenser, a heat exchanger, and a flue gas desulfurization equipment for ecology systems and chemical plants.
| Cr | Ni | Mo | N | 0.2% resistance (N/m㎡) | tension resistance(N/m㎡) | Pitting-factor | |
|---|---|---|---|---|---|---|---|
| SA790 UNSNO.S32750 | 24.8% | 6.7% | 3.5% | 0.26% | more than 550 | more than 795 | 40.5 |
| SUS329J4L | 24% | 6.5% | 2.6% | 0.13% | more than 450 | more than 620 | 35 |
| SA790 UNSNO.S31803 | 22％ | 5.5% | 3% | 0.15％ | more than 450 | more than 620 | 34 |
| SUS304 | 18% | 8% | - | - | more than 205 | more than 520 | 18 |
| SUS316L | 16% | 12% | 2% | - | more than 205 | more than 520 | 24 |
*It is called super stainless steel if its pitting-factor is more than 40.
*SA790 The data for UNSNO.S32750, S31803, and SUS329J4L is inspected by Yamamoto Special Steel.
Characteristics of Duplex Stainless Steel
■It has two phases of metallographic structure of austenite and ferrite. It is tougher than austenite type metals such as SUS304 and 316L and has excellent crevice corrosion resistance and corrosion cracking resistance.
■It is twice as strong as SUS304 and 316L so that it can be designed thinner. It is, thus, eventually made at lower cost.
■By adding molybdenum(Mo) and nitrogen(N) as well as chrome(Cr) and nikkel(Ni), it is able to gain a variety of corrosion resistances from duplex steel class and super duplex steel class - when its pitting-factor is more than 40 - at wide range of prices.
Main purposes
As a material for chemical equipment, it is used as a seawater condenser, a heat exchanger, a flue gas desulfurization equipment, and cutting platform for petrol development.
| External diameter (mm) | Thickness (mm) | Length (mm) | finishing | Weight kg/m | |
|---|---|---|---|---|---|
| 329J4LTPSC | 6 | 1 | 4000 | C | 0.123 |
| 8 | 1 | 4000 | C | 0.172 | |
| 10 | 1 | 4000 | C | 0.221 | |
| 12 | 1 | 4000 | C | 0.27 | |
| 13.8 | 2.2 | 4000 | C | 0.625 | |
| 17.3 | 2 | 4000 | C | 0.75 | |
| 17.3 | 2.3 | 4000 | C | 0.845 | |
| 21.7 | 2.1 | 4000 | C | 1.01 | |
| 21.7 | 2.8 | 4000 | C | 1.3 | |
| 3.7 | 4000 | C | 1.63 | ||
| 27.2 | 2.1 | 4000 | C | 1.29 | |
| 2.9 | 4000 | C | 1.73 | ||
| 3.9 | 4000 | C | 2.23 | ||
| 34 | 2.8 | 4000 | C | 2.14 | |
| 3 | 4000 | C | 2.28 | ||
| 3.4 | 4000 | C | 2.55 | ||
| 4.5 | 4000 | C | 3.25 | ||
| 48.6 | 2.8 | 4000 | C | 3.14 | |
| 3.7 | 4000 | C | 4.07 | ||
| 5.1 | 4000 | C | 5.44 | ||
| 60.5 | 2.8 | 4000 | C | 3.96 | |
| 3.9 | 4000 | C | 5.41 | ||
| 5.5 | 4000 | C | 7.41 | ||
| 89.1 | 3 | 4000 | C | 6.33 | |
| 5.5 | 4000 | C | 11.3 | ||
| 7.6 | 4000 | C | 15.2 | ||
| 114.3 | 3 | 4000 | C | 8.18 | |
| 6 | 4000 | C | 15.9 | ||
| 8.6 | 4000 | C | 22.3 | ||
| 139.8 | 5 | 4000 | C | 16.5 | |
| 165.2 | 5 | 4000 | C | 19.6 | |
| SA790 UNSNO.S31803 | 21.3 | 2.77 | 6000 | C | 1.26 |
| 3.73 | 6000 | C | 1.61 | ||
| 26.7 | 2.87 | 6000 | C | 1.68 | |
| 3.91 | 6000 | C | 2.18 | ||
| 33.4 | 3.38 | 6000 | C | 2.49 | |
| 4.55 | 6000 | C | 3.22 | ||
| 48.3 | 3.68 | 6000 | C | 4.02 | |
| 5.08 | 6000 | C | 5.38 | ||
| 60.3 | 3.91 | 6000 | C | 5.4 | |
| 5.54 | 6000 | C | 7.43 | ||
| 88.9 | 5.49 | 6000 | C | 11.2 | |
| 114.3 | 6.02 | 6000 | C | 16 | |
| SA790 UNSNO.S32750 | 21.3 | 2.77 | 6000 | C | 1.26 |
| 3.73 | 6000 | C | 1.61 | ||
| 26.7 | 2.87 | 6000 | C | 1.68 | |
| 3.91 | 6000 | C | 2.18 | ||
| 33.4 | 3.38 | 6000 | C | 2.49 | |
| 4.55 | 6000 | C | 3.22 | ||
| 48.3 | 3.68 | 6000 | C | 4.02 | |
| 5.08 | 6000 | C | 5.38 | ||
| 60.3 | 3.91 | 6000 | C | 5.4 | |
| 5.54 | 6000 | C | 7.43 | ||
| 88.9 | 5.49 | 6000 | C | 11.2 | |
| 114.3 | 6.02 | 6000 | C | 16 |
*It is called super stainless steel if its pitting-factor is more than 40.
*SA790 The data for UNSNO.S32750, S31803, and SUS329J4L is inspected by Yamamoto Special Steel.
