ASTM A403 Standard specification covers the standard for wrought austenitic stainless steel fittings for pressure piping applications. ASTM A403 / A403M Standard Specification for Wrought Austenitic Stainless Steel Piping Fittings.
ASTM A403 WPL6 Elbow after complete quality and performance measure inspection. These are widely appreciated for excellent quality, corrosion abrasion and high tensile strength with long life service.
The material for fittings shall consist of forgings, bars, plates, or seamless or welded tubular products. Forging or shaping operations shall be performed by hammering, pressing, piercing, extruding, upsetting, rolling, bending, fusion welding, machining, or by a combination of two or more of these operations. All fittings shall undergo heat-treatment. Chemical and product analyses shall be performed and shall conform to the required chemical composition in carbon, manganese, phosphorus, sulfur, silicon, chromium, molybdenum, and titanium. Tension test shall be done on the fitting material to determine the tensile properties such as yield strength and tensile strength. Fittings supplied under this specification shall be examined visually for surface discontinuities, surface checks, and mechanical marks.
This abstract is a brief summary of the referenced standard. It is informational only and not an official part of the standard; the full text of the standard itself must be referred to for its use and application. ASTM does not give any warranty express or implied or make any representation that the contents of this abstract are accurate, complete or up to date.
Wrought Austenitic Stainless Steel Piping Fittings
Materials shall consist of forgings, bars, plates, seamless or fusion welded tubular products with filler metal added, and shall be produced by open-hearth, basic-oxygen, or electric-furnace process. Forging or forming operations shall be performed by one or a combination of two or more of the following procedures: hammering, pressing, piercing, extruding, upsetting, working, bending, fusion-welding, or machining. All welding shall be completed prior to the austenitizing heat treatment, which shall be executed in the normalized, normalized and tempered, annealed, or quenched and tempered conditions. Steel specimens shall conform to required values of chemical composition, tensile strength, yield strength, elongation, wall thickness, and Charpy V-notch impact value. All fusion-welded butt joints shall undergo radiographic examination, while hydrostatic testing of fittings is not required in this specification. Repair welding shall be permissible for parts made to dimensional standards.
This abstract is a brief summary of the referenced standard. It is informational only and not an official part of the standard; the full text of the standard itself must be referred to for its use and application. ASTM does not give any warranty express or implied or make any representation that the contents of this abstract are accurate, complete or up to date.
Scope of ASTM A403
1.1 This specification covers wrought carbon steel and alloy steel fittings of seamless and welded construction, covered by the latest revision of ASME B16.9, ASME B16.11, MSS SP-79, MSS SP-83, MSS SP-95, and MSS SP-97. Fittings differing from these ASME and MSS standards shall be furnished in accordance with Supplementary Requirement S58 of Specification A960/A960M. These fittings are for use in pressure piping and pressure vessel service at low temperatures.
1.2 Optional supplementary requirements are provided for fittings where a greater degree of examination is desired. When desired, one or more of these supplementary requirements shall be specified in the order.
1.3 This specification is expressed in both inch-pound units and in SI units. However, unless the order specifies the applicable “M” specification designation (SI units), the material shall be furnished to inch-pound units.
1.4 The values stated in either SI units or inch-pound units are to be regarded separately as standard. Within the text, the SI units are shown in brackets. 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.
Chemical Composition (%) of ASTM A403
| Steel No. | Type | C | Si | S | P | Mn | Cr | Ni | Mo | Other | ób | ós | δ5 |
|---|---|---|---|---|---|---|---|---|---|---|---|---|---|
| WP304 | 0.08 | 1 | 0.03 | 0.045 | 2 | 18-20 | 8-11 | 515 | 205 | 28 | |||
| WP304H | 0.04-0.1 | 1 | 0.03 | 0.045 | 2 | 18-20 | 8-11 | 515 | 205 | 28 | |||
| WP304L | 0.035 | 1 | 0.03 | 0.045 | 2 | 18-20 | 8-13 | 485 | 170 | 28 | |||
| WP304LN | 0.03 | 0.75 | 0.03 | 0.045 | 2 | 18-20 | 8-10.5 | N2:0.1-0.16 | 515 | 205 | 28 | ||
| WP304N | 0.08 | 0.75 | 0.03 | 0.045 | 2 | 18-20 | 8-11 | N2:0.1-0.16 | 550 | 240 | 28 | ||
| WP309 | 0.15 | 1 | 0.03 | 0.045 | 2 | 22-24 | 12-15 | 515 | 205 | 28 | |||
| WP310 | 0.15 | 1.5 | 0.03 | 0.045 | 2 | 24-26 | 19-22 | 515 | 205 | 28 | |||
| WP316 | 0.08 | 1 | 0.03 | 0.045 | 2 | 16-18 | 10-14 | 2-3 | 515 | 205 | 28 | ||
| WP316H | 0.04-0.1 | 1 | 0.03 | 0.045 | 2 | 16-18 | 10-14 | 2-3 | 515 | 205 | 28 | ||
| WP316LN | 0.03 | 0.75 | 0.03 | 0.045 | 2 | 16-18 | 11-14 | 2-3 | N2:0.1-0.16 | 515 | 205 | 28 | |
| WP316L | 0.035 | 1 | 0.03 | 0.045 | 2 | 16-18 | 10-16 | 2-3 | 485 | 170 | 28 | ||
| WP316N | 0.08 | 0.75 | 0.03 | 0.045 | 2 | 16-18 | 11-14 | 2-3 | N2:0.1-0.16 | 550 | 240 | 28 | |
| WP317 | 0.08 | 1 | 0.03 | 0.045 | 2 | 18-20 | 11-15 | 3-4 | 515 | 205 | 28 | ||
| WP317L | 0.03 | 1 | 0.03 | 0.045 | 2 | 18-20 | 11-15 | 3-4 | 515 | 205 | 28 | ||
| WP321 | 0.08 | 1 | 0.03 | 0.045 | 2 | 17-20 | 9-13 | Ti:5C-0.7 | 515 | 205 | 28 | ||
| WP321H | 0.04-0.1 | 1 | 0.03 | 0.045 | 2 | 17-20 | 9-13 | Ti:4C-0.7 | 515 | 205 | 28 | ||
| WP347 | 0.08 | 1 | 0.03 | 0.045 | 2 | 17-20 | 9-13 | Nb+Ta:10C-1.1 | 515 | 205 | 28 | ||
| WP347H | 0.04-0.1 | 1 | 0.03 | 0.045 | 2 | 17-20 | 9-13 | Nb+Ta:8C-1 | 515 | 205 | 28 | ||
| WP348 | 0.08 | 1 | 0.03 | 0.045 | 2 | 17-20 | 9-13 | Ta:0.1 | 515 | 205 | 28 | ||
| WP348H | 0.04-0.1 | 1 | 0.03 | 0.045 | 2 | 17-20 | 9-13 | Ta:0.1 | 515 | 205 | 28 |
For each reduction of 0.01% below the specified C maximum, an increase of 0.06% Mn above the specified maximum will be permitted, up to a maximum of 1.35%.
The sum of Cu, Ni, Cr, and Mo shall not exceed 1.00%.
The sum of Cr and Mo shall not exceed 0.32%.
The maximum carbon equivalent (C.E.) shall be 0.50, based on heat analysis and the formula C.E.=C+Mn/6+(Cr+Mo+V)/5+(Ni+Cu)/15.
Mechanical properties of ASTM A403
| Grade | UNS | Tensile Strength, min | Yield Strength,min | Elongation min % in 4D | |||
|---|---|---|---|---|---|---|---|
| ksi | MPa | ksi | MPa | Longit % | Trans% | ||
| ALL | ALL | 75 | 515 | 30 | 205 | 28 | 20 |
| 304L | S30403 | 70 | 485 | 25 | 170 | 28 | 20 |
| 316L | S31603 | 70 | 485 | 25 | 170 | 28 | 20 |
| 304N | S30451 | 80 | 550 | 35 | 240 | 28 | 20 |
| 316N | S31651 | 80 | 550 | 35 | 240 | 28 | 20 |
| S31726 | 80 | 550 | 35 | 240 | 28 | 20 | |
| XM-19 | S20910 | 100 | 690 | 55 | 380 | 28 | 20 |
| S31254 | 94-119 | 650-820 | 44 | 300 | 28 | 20 | |
| S34565 | 115 | 795 | 60 | 415 | 28 | 20 | |
| S33228 | 73 | 500 | 27 | 185 | 28 | 20 | |
Material Furnished to this specification shall conform to the requirements of specifications A960/A960M including any supplementary requirements that are indicates in the purchase order. Failure to company with the common requirements of Specification A960/A960M constitutes non-conformance with this specification. In case of conflict between this specification and Specification A960/A960M , this specification shall prevail.
What grade of steel is ASTM A403?
The standard includes several grades of austenitic stainless steel alloys, and uses the WP or CR prefix to mark the grade of steel, depending on the applicable ASTM or MSS size and rated pressure standards. ASTM A403 is designed for forged steel pipe fittings, Cast pipe fittings are not suitable.