ANSI B16.9 A403 Wp321 Seamless Pipe Fitting Tee
ASTM A403 WP321 covers the standard for wrought austenitic stainless steel fittings for pressure piping applications. 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.
- A butt weld pipe fitting is designed to be welded on site at its end(s) to connect pipe(s) together and allow change in direction or pipe diameter, or branching or ending.
- This fitting then becomes part of a system for transporting fluids (oil, gas, steam, chemicals, …) in a safe and efficient manner, over short or long distances.
- Other types of fittings can be threaded or socket welded.
Several grades of austenitic stainless steel alloys are included in this specification. Grades are designated with a prefix, based on the applicable ASTM/ASME or MSS standards. For each of the WP stainless grades, several classes of fittings are specified, to indicate whether seamless or welded construction was utilized. Class designations are also utilized to indicate the nondestructive test method and extent of nondestructive examination. A general summary of the fitting classes applicable to all WP grades of stainless steel follows. There are no classes for the CR grades
ASTM A403 WP321H Chemical Composition
| Grade |
C |
Mn |
Si |
P |
S |
Cr |
N |
Ni |
Ti |
| SS 321 |
0.08 max |
2.0 max |
1.0 max |
0.045 max |
0.030 max |
17.00 - 19.00 |
0.10 max |
9.00 - 12.00 |
5(C+N) - 0.70 max |
| SS 321H |
0.04 - 0.10 |
2.0 max |
1.0 max |
0.045 max |
0.030 max |
17.00 - 19.00 |
0.10 max |
9.00 - 12.00 |
4(C+N) - 0.70 max |
ASTM A403 SS 321 Butt weld Pipe Fittings Mechanical Properties
| Density |
Melting Point |
Tensile Strength |
Yield Strength (0.2%Offset) |
Elongation |
| 8.0 g/cm3 |
1457 °C (2650 °F) |
Psi - 75000 , MPa - 515 |
Psi - 30000 , MPa - 205 |
35 % |
ASTM A403 WP321 Stainless Steel Pipe Fittings Specification
Specifications : ASTM A403 / ASME SA403
Dimensions : ASME/ANSI B16.9, ASME B16.28, MSS-SP-43
Size : 1/8" NB TO 48" NB. (Seamless & 100% X-Ray Welded, Fabricated)
Type : Seamless / Welded / Fabricated
Bending Radius : R=1D, 2D, 3D, 5D, 6D, 8D, 10D or Custom
Thickness : Sch 5s, Sch 10s, Sch 40s, Sch 80s, Sch 160s, Sch XXS
Company Profile
From 1989 to now, Kingmetal Steel focus on manufacturing and distributing pipeline products including piping, fitting, flange, valve and fastener in stainless, carbon, alloy and duplex steel.
Kingmetal has a factory to manufacture seamless stainless steel pipe from DN6 to DN600 and distribute seamless steel pipe and fitting from top brand manufacturers such as Baosteel, Hengsteel, Tiansteel and Pansteel etc.
All of products are strictly compliance with standard, 100% inspection passed including visual, dimension and PMI test before shipment.
Both our sales and logistic teams are over 10 years of experiences and training frequently.
After- sales service with high efficiency, if any products are short quantity/weight or damaged caused by manufacturing, design or transportation can be compensated.
Why choose us?
One-Stop Solution
We have thousands of total production experience, from raw materials to finished products.
Competitive Price
Large scale purchase, standardized production process and efficient management make our price competitive.
Quick Shipping
Years of export experience enable us to control the transportation time more accurately.
Quality Control
The standardized production process, comprehensive management system, professional testing equipment
Special material customization
We support the customization of various complex materials
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