Duplex Steel Tube Duplex Steel Pipe Manufacturer
Guanyu Tube is a Specialized Manufacturer of Duplex stainless steel pipe (DSS). ASTM A789 SA789 S31803 S32205 2205 Duplex Tubes and ASTM A790 SA790 S31803 S32205 2205 Duplex Pipes.
Duplex Steel is featured with a structure of two phases (α and γ) and has characteristics of both ferritic and austenitic stainless steel. It has good corrosion resistance and high strength. It is alloyed with 18%-28% Cr and 3%-10% Ni in the condition of low Carbon. Some steels also contain the alloy elements such as Mo, Cu, Nb, Ti and N, etc. Compared with ferritic stainless, duplex stainless steel has higher plasticity, ductility and better intergranular corrosion resistance and weldability. It keeps the same 475°C brittleness with ferritic stainless and high thermal conductivity. Duplex has improved yield strength, resistance to intergranular corrosion, stress corrosion, corrosion fatigue and abrasion & corrosion compared with austenitic stainless steel.
- Duplex Tubes Duplex Steel Pipe Features
- Duplex Tube Material Duplex Steel Pipe Material Grade
- Duplex Steel Tube Grade Comparison Chart
- Duplex Pipe Duplex Steel Tube Chemical Composition
- Duplex Tubes Standard Specifiation Duplex Steel Pipe Standard Specification
- Duplex Tube Duplex Pipe Mechanical Properties
- Duplex Steel Tubes Main Testing Terms and Procedure
- Duplex Steel Pipe and Duplex Tube Marking & Packing
- Duplex Steel Tube Ordering Information
- Duplex Steel Tube Product Analysis
- Duplex Tubes Duplex Steel Pipes Heat Treatment
- Duplex Steel Tubing Duplex Steel Pipe Related link
Duplex Tubes Duplex Steel Pipe Features
1.Superior resistance to general and local corrosion, especially to stress corrosion, pitting corrosion, crevice corrosion, corrosion fatigue and abrasion & corrosion.
2.Good weldability
3.Good mechanical properties
4.Excellent intergranular corrosion resistance
5.High cost-effectiveness, long life time
Duplex Tube Material Duplex Steel Pipe Material Grade
Alloy 2205 UNS S32305/S31803 is a 22% chromium, 3% molybdenum, 5-6% nickel, nitrogen alloyed Duplex Stainless Steel Pipe with high general, localized, and stress corrosion resistance properties in addition to high strength and excellent impact toughness.
Alloy 2205 provides pitting and crevice corrosion resistance superior to 316L or 317L austenitic stainless steel tube in almost all corrosive media. It also has high corrosion and erosion fatigue properties as well as lower thermal expansion and higher thermal conductivity than austenitic.
2101 is a low nickel, lean duplex stainless steel possessing both superior strength and chloride stress-corrosion cracking resistance when compared to 300 series stainless steel.
2304 A lean austenitic-ferritic duplex stainless steel with general corrosion resistance similar to 316, but with yield strength nearly double that of austenitic stainless steel.
S31803 and S32205 are standard duplex stainless steel. A nitrogen, molybdenum enhanced austenitic-ferritic duplex stainless steel with general corrosion resistance similar to 904L, but with a yield strength nearly double that of austenitic stainless steel.
2507 (PREN 40-45), with 25-26 Cr and increased Mo and N compared with the 25Cr grades. A super austenitic-ferritic duplex stainless steel with exceptional strength and corrosion resistance ideal for chemical process, petrochemical, and seawater applications.
Duplex Steel Tube Grade Comparison Chart
| China GB | ISO Unified Digital Code | ASTM / ASME | UNS code | EN Code | Company Commercial Grade |
| 022Cr23Ni4MoCuN | S23043 | S32304 | S32304 | 1.4362 | SAF2304 (Sandvik) |
| 022Cr22Ni5Mo3N | S22253 | S31803 | S31803 | 1.4462 | – |
| 022Cr23Ni5Mo3N | S22053 | S32205 | S32205 | 1.4462 | SAF2205 (Sandvik) |
| 022Cr25Ni7Mo4N | S25073 | S32750 | S32750 | 1.4410 | SAF2507(Sandvik) |
| 022Cr25Ni7Mo3WCuN | S22583 | S31260 | S31260 | – | – |
| 03Cr25Ni6Mo3Cu2N | S25554 | S32550 | S32550 | 1.4507 | UR52+ |
| 022Cr25Ni7Mo4WCuN | S27603 | S32760 | S32760 | 1.4501 | Zeron100 |
| 00Cr27Ni7Mo5N | – | S32707 | S32707 | – | SAF2707(Sandvik) |
Duplex Pipe Duplex Steel Tube Chemical Composition
Chemical Composition According to ASME SA789 ASTM A789
| Designation | C | Mn | P | S | Si | Ni | Cr | Mo | N | Cu | Others |
| S31200 | 0.030 | 2.00 | 0.045 | 0.030 | 1.00 | 5.5–6.5 | 24.0–26.0 | 1.20–2.00 | 0.14–0.20 | . . . | . . . |
| S31260 | 0.030 | 1.00 | 0.030 | 0.030 | 0.75 | 5.5–7.5 | 24.0–26.0 | 2.5–3.5 | 0.10–0.30 | 0.20 –0.80 | W 0.10 –0.50 |
| S31500 | 0.030 | 1.20 –2.00 | 0.030 | 0.030 | 1.40 –2.00 | 4.3–5.2 | 18.0–19.0 | 2.50–3.00 | 0.05–0.1 | . . . | . . . |
| 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 | . . . | . . . |
| S32001 | 0.030 | 4.00 –6.00 | 0.040 | 0.030 | 1.00 | 1.0–3.0 | 19.5–21.5 | 0.60 | 0.05–0.17 | 1.00 | . . . |
| S32003 | 0.030 | 2.00 | 0.030 | 0.020 | 1.00 | 3.0-4.0 | 19.5-22.5 | 1.50-2.00 | 0.14-0.20 | . . . | . . . |
| S32101 | 0.040 | 4.0-6.0 | 0.040 | 0.030 | 1.00 | 1.35-1.70 | 21.0-22.0 | 0.10-0.80 | 0.20-0.25 | 0.10 -0.80 | . . . |
| S32202 | 0.030 | 2.00 | 0.040 | 0.010 | 1.00 | 1.00–2.80 | 21.5–24.0 | 0.45 | 0.18–0.26 | . . . | . . . |
| 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 | . . . |
| S32506 | 0.030 | 1.00 | 0.040 | 0.015 | 0.90 | 5.5–7.2 | 24.0–26.0 | 3.0–3.5 | 0.08–0.20 | . . . | W 0.05 –0.30 |
| S32520 | 0.030 | 1.50 | 0.035 | 0.020 | 0.80 | 5.5–8.0 | 23.0–25.0 | 3.–5. | 0.20–0.35 | 0.50 –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 | . . . |
| S32707 | 0.030 | 1.50 | 0.035 | 0.010 | 0.50 | 5.5–9.5 | 26.0–29.0 | 4.0–5.0 | 0.30–0.50 | 1.0 max | Co 0.5 –2.0 |
| 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 | 0.50 | . . . |
| S32760 | 0.030 | 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 | W 0.50 –1.00 |
| S32808 | 0.030 | 1.10 | 0.030 | 0.010 | 0.50 | 7.0–8.2 | 27.0–27.9 | 0.80–1.20 | 0.30–0.40 | . . . | W 2.10 –2.50 |
| S32900 | 0.08 | 1.00 | 0.040 | 0.030 | 0.75 | 2.5–5.0 | 23.0–28.0 | 1.00–2.00 | . . . | . . . | . . . |
| S32906 | 0.030 | 0.80 –1.50 | 0.030 | 0.030 | 0.80 | 5.8–7.5 | 28.0 –30.0 | 1.50–2.60 | 0.30–0.40 | 0.80 | . . . |
| S32950 | 0.030 | 2.00 | 0.035 | 0.010 | 0.60 | 3.5–5.2 | 26.0–29.0 | 1.00–2.50 | 0.15–0.35 | . . . | . . . |
| S33207 | 0.030 | 1.50 | 0.035 | 0.010 | 0.80 | 6.0–9.0 | 29.0–33.0 | 3.0–5.0 | 0.40–0.60 | 1.0 | . . . |
| S39274 | 0.030 | 1.00 | 0.030 | 0.020 | 0.80 | 6.0–8.0 | 24.0–26.0 | 2.5–3.5 | 0.24–0.32 | 0.20 –0.80 | W 1.50 –2.50 |
| S39277 | 0.025 | 0.80 | 0.025 | 0.002 | 0.80 | 6.5–8.0 | 24.0–26.0 | 3.00–4.00 | 0.23–0.33 | 1.20 –2.00 | W 0.80 –1.21 |
| S82011 | 0.030 | 2.0 –3.0 | 0.040 | 0.020 | 1.00 | 1.00–2.00 | 20.5–23.5 | 0.10–1.00 | 0.15–0.27 | 0.50 | . . . |
| S82441 | 0.030 | 2.50 –4.00 | 0.035 | 0.005 | 0.70 | 3.0–4.5 | 23.0–25.0 | 1.00–2.00 | 0.20–0.30 | 0.10 –0.80 |
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 be determined or reported.
B Designation established in accordance with Practice E527 and SAE J1086.
C % Cr + 3.3 × % Mo + 16 × % N $ 41.
D % Cr + 3.3 × % Mo + 16 × % N $ 40.
Duplex Tubes Standard Specifiation Duplex Steel Pipe Standard Specification
- ASTM A789 (ASME SA789) Standard Specification for Seamless and Welded Ferritic/Austenitic Stainless Steel Tubing for General Service
- ASTM A790 (ASME SA790) Standard Specification for Seamless and Welded Ferritic/Austenitic Stainless Steel Pipe
- ASTM A923 Standard Test Methods for Detecting Detrimental Intermetallic Phase in Duplex Austenitic/Ferritic Stainless Steel
- ASTM A928 Standard Specification for Ferritic/Austenitic (Duplex) Stainless Steel Pipe Electric Fusion Welded with Addition of Filler Metal
- EN 10216-5 Seamless steel tubes for pressure purposes
- GB/T 21832-2008 Austenitic–Ferritic(duplex) grade stainless steel welded tubes and pipes
- GB/T 21833-2008 Austenitic-Ferritic (duplex) grade stainlee steel seamless tubes and pipes
Referenced Documents
ASTM Standards:
A480/A480M Specification for General Requirements for Flat-Rolled Stainless and Heat-Resisting Steel Plate, Sheet, and Strip
A1016/A1016M Specification for General Requirements for Ferritic Alloy Steel, Austenitic Alloy Steel, and Stainless Steel Tubes
E527 Practice for Numbering Metals and Alloys in the Unified Numbering System (UNS)
SAE Standard:
SAE J 1086 Practice for Numbering Metals and Alloys (UNS)
Duplex Tube Mechanical Properties
1. Tension Tests—One tension test shall be made on a specimen for lots of not more than 50 tubes. Tension tests shall be made on specimens from two tubes for lots of more than 50 tubes (see Note 2).
2. Flaring Test (for Seamless Tubes)—One test shall be made on specimens from one end of one tube from each lot (see Note 1) of finished tubes. The minimum expansion of the inside diameter shall be 10 %.
3. Flange Test (for Welded Tubes)—One test shall be made on specimens from one end of one tube from each lot (see Note1) of finished tubes.
4. Hardness Test—Brinell hardness tests or Rockwell hardness tests shall be made on specimens from two tubes from each lot (see Note 2).
5. When more than one heat is involved, the tension, flaring, flanging, and hardness test requirements shall apply to each heat.
6. Reverse Flattening Test—For welded tubes, one reverse flattening test shall be made on a specimen from each 1500 ft [450 m] of finished tubing.
Tensile Strength and Hardness Requirements
11.1 The material shall conform to the tensile and hardness properties prescribed in Table 4.
| Grade | Tensile strength, min., ksi [MPa] | Yield strength, min., ksi [MPa] | Elongation in 2 in., or 50mm, min, % | Hardness, Max Brinell |
| S31803 | 90 [620] | 65 [450] | 25 | 290 |
| S32205 | 95 [655] | 70 [485] | 25 | 290 |
| S31500 | 92 [630] | 64 [440] | 30 | 290 |
| S32550 | 110 [760] | 80 [550] | 15 | 297 |
| S31200 | 100 [690] | 65 [450] | 25 | 280 |
| S31260 | 100 [690] | 65 [450] | 25 | 290 |
| S32001 | 90 [620] | 65 [450] | 25 | 290 |
| S32304 | 100 [690] | 65 [450] | 25 | 290 |
| S32750 | 116 [800] | 80 [550] | 15 | 310 |
| S32760 | 109 [750] | 80 [550] | 25 | 300 |
| S32950 | 100 [690] | 70 [480] | 20 | 290 |
| S32520 | 112 [770] | 80 [550] | 25 | 310 |
For tubing smaller than 1⁄2 in. [12.7 mm] in outside diameter, the elongation values given for strip specimens in Table 4 shall apply. Mechanical property requirements do not apply to tubing smaller than 1⁄8 in. [3.2 mm] in outside diameter or with walls thinner than 0.015 in. [0.4 mm].
Prior to A789/A789M–04, the values for S32003 were 90 ksi tensile strength and 65 ksi yield strength.
Duplex Steel Tubes Main Testing Terms and Procedure
- 1. Heat Treatment and Solution Annealing / Bright Annealing
- 2. Cutting to required length and deburring;
- 3. Chemical Composition Analysis Test With 100% PMI and One tube from each heat by Direct Reading Spectrometer
- 4. Visual Test and Endoscope Test for Surface Quality Test
- 5. 100% Hydrostatic Test and 100% Eddy Current Test
- 6. Ultrasonic Test subject to the MPS (Material Purchase Specification)
- 7. Mechanical Tests includes Tension Test, Flattening Test, Flaring Test, Hardness Test
- 8. Impact Test subject to Standard request
- 9. Grain Size Test and Intergranular Corrosion Test
- 10. Ultrasoic measuring of Wall Thickness
Duplex Steel Pipe and Duplex Tube Marking & Packing
Marking according to MPS and Standard
Stainless Steel Tubes Ends with Caps according to PO
In Seaworthy Wooden Cases With Plastic Paper protect
In Plywood Cases With Plastic Paper Protect(Recommend, All Plywood Cases made by ourselves with lower cost.)
Steel Racks Package
Hexagonal packing in Bundles
Duplex Steel Pipe Product Marking
In addition to the marking prescribed in Specification A1016/A1016M, the marking shall indicate whether the tubing is seamless or welded and the wall designation (average wall or minimum wall).
ASTM A789 / ASME SA789 covers grades of average wall thickness, or, if specified on the order, minimum wall thickness, of stainless steel tubing for services requiring general corrosion resistance, with particular emphasis on resistance to stress corrosion cracking. These steels are suscep- tible to embrittlement if used for prolonged periods at elevated temperatures.
The values stated in either SI units or inch-pound units are to be regarded separately as standard. The values stated in each system may not be exact equivalents; therefore, each system shall be used independently of the other. Combining values from the two systems may result in non-conformance with the standard. Within the text, the SI units are shown in brackets. The inch-pound units shall apply unless the M designation of this specification is specified in the order.
Duplex Steel Tube Ordering Information
Orders for product under this specification should in- clude the following, as required, to describe the desired material adequately:
Quantity (feet, metres, or number of lengths),
Name of product (seamless or welded tubes),
Grade
Size (outside diameter and average wall thickness, unless minimum wall thickness is specified),
Length (specific or random),
Optional requirements (for product analysis, see Section for hydrostatic or nondestructive electric test, see Section 10
Test report required (see the Inspection section of Specification A1016/A1016M
Specification designation, and
Special requirements.
General Requirements
Product furnished under this specification shall conform to the applicable requirements of specification A1016/ A1016M, unless otherwise provided herein.
Manufacture
The tubes shall be made by the seamless or welded process with no filler metal added.
Duplex Steel Tube Product Analysis
1. An analysis of either one billet or one length of flat-rolled stock or one tube shall be made from each heat. The chemical composition thus determined shall conform to the requirements specified.
2. A product analysis tolerance (see the annex table on Chemical Requirements (Product Analysis Tolerances) in Specification A480/A480M) shall apply. The product analysis tolerance is not applicable to the carbon content for material with a specified maximum carbon of 0.04 % or less.
3. If the original test for product analysis fails, retests of two additional billets, lengths of flat-rolled stock, or tubes shall be made. Both retests for the elements in question shall meet the requirements of this specification; otherwise, all remaining material in the heat shall be rejected or, at the option of the producer, each billet or tube may be individually tested for acceptance. Billets, lengths of flat-rolled stock, or tubes that do not meet the requirements of this specification shall be re- jected.
NOTE 1—For flange and flaring requirements, the term lot applies to all tubes prior to cutting of the same nominal size and wall thickness that are produced from the same heat of steel. When final heat treatment is in a batch-type furnace, a lot shall include only those tubes of the same size and from the same heat that are heat treated in the same furnace charge. When the final heat treatment is in a continuous furnace, or when heat treated condition is obtained directly by quenching after hot forming, the number of tubes of the same size and from the same heat in a lot shall be determined from the size of the tubes as prescribed in Table 3.
NOTE 2—For tension and hardness test requirements, the term lot applies to all tubes prior to cutting, of the same nominal diameter and wall thickness that are produced from the same heat of steel. When final heat treatment is in a batch-type furnace, a lot shall include only those tubes of the same size and the same heat that are heat treated in the same furnace charge. When the final heat treatment is in a continuous furnace, or when heat treated condition is obtained directly by quenching after hot forming, a lot shall include all tubes of the same size and heat, heat treated in the same furnace at the same temperature, time at heat, and furnace speed, or all tubes of the same size and heat, hot formed and quenched in the same production run.
Hydrostatic or Nondestructive Electric Test
1 Each tube shall be subjected to the nondestructive electric test or the hydrostatic test. The type of test to be used shall be at the option of the manufacturer, unless otherwise specified in the purchase order.
2. The hydrostatic test shall be in accordance with Speci- fication A1016/A1016M, except that in the calculation of the hydrostatic test pressure 64000(441.2) shall be substituted for 32000(220.6).
Duplex Tubes Duplex Steel Pipes Heat Treatment
All tubes shall be furnished in the heat-treated condition in accordance with the procedures shown in Table 2. For seamless tubes, as an alternate to final heat treatment in a continuous furnace or batch-type furnace, immediately follow- ing hot forming while the temperature of the tubes is not less than the specified minimum solution treatment temperature, tubes may be individually quenched in water or rapidly cooled by other means.
Table.2 Heat Treatment
| UNS Designation | Temperature | Quenching |
| S31803 | 1870-2010 °F [1020-1100°C] | Rapid cooling in air or water |
| S32205 | 1870-2010 °F [1020-1100°C] | Rapid cooling in air or water |
| S31500 | 1800-1900 °F [980-1040°C] | Rapid cooling in air or water |
| S32550 | 1900 °F [1040°C] min. | Rapid cooling in air or water |
| S31200 | 1920-2010 °F [1050-1100°C] | Rapid cooling in water |
| S31260 | 1870-2010 °F [1020-1100°C] | Rapid cooling in water |
| S32001 | 1800-1950 °F [982-1066°C] | Rapid cooling in air or water |
| S32003 | 1850-2050 °F [1010-1120°C] | Rapid cooling in air or water |
| S32101 | 1870 °F min | Quenched in water or Rapidly cooling in other means |
| S32202 | 1870-1975 °F [1020-1080°C] | Rapid cooling in air or water |
| S32506 | 1870-2050 °F [1020-1120°C] | Rapid cooling in air or water |
| S32304 | 1700-1920 °F [925-1050°C] | Rapid cooling in air or water |
| S32750 | 1880-2060 °F [1025-1125°C] | Rapid cooling in air or water |
| S32760 | 2010-2085 °F [1100-1140°C] | Rapid cooling in air or water |
| S32950 | 1820-1880 °F [990-1025°C] | Rapid cooling in water |
| S32520 | 1975-2050 °F [1080-1120°C] | Rapid cooling in air or water |
Duplex Steel Tubes Permissible Variations in Dimensions
1 Variations in outside diameter, wall thickness, and length from those specified shall not exceed the amounts prescribed in Table 5.
2 The permissible variations in outside diameter given in Table 5 are not sufficient to provide for ovality in thin-walled tubes, as defined in the table. In such tubes, the maximum and minimum diameters at any cross section shall deviate from the nominal diameter by no more than twice the permissible variation in outside diameter given in Table 5; however, the mean diameter at that cross section must still be within the given permissible variation.
Duplex Tube Surface Condition
All tubes shall be free of excessive mill scale, suitable for inspection. A slight amount of oxidation will not be considered as scale. Any special finish requirements shall be subject to agreement between the manufacturer and the purchaser.