ASTM A403 Pipe Fittings

ASTM A403 Pipe Fittings are characterized by high-quality stainless steel materials, commonly available in grades like 304 and 316, offering excellent corrosion resistance and strength.

A403 Pipe Fittings of Wrought Stainless Steel for Corrosion Resistance, High-Temperature Strength, & Durability.

SSM produces ASTM A403 Pipe Fittings, which primarily focus on the manufacturing requirements for stainless steel fittings. These fittings include elbows, tees, reducers, and are widely used to connect piping systems. The ASTM A403 standard ensures consistency and reliability in the chemical composition, mechanical properties, dimensions, and surface quality of the fittings, making them suitable for various industries, including oil, chemicals, food processing, and water treatment, while being capable of withstanding high temperatures and pressures.

A403 wrought stainless steel piping fittings supplier, SSM provides product parameters as shown in the following table:

Items	Parameters
OD	NPS 1/8″ – 4″ for Forged Threaded and Socket-Welding Fittings / NPS 1⁄2″- 48″ for Wrought Buttwelding Fittings
Class / WT	2000 3000 6000 / SCH5S-SCHXXS
Types	Elbow / Cross / Tee / Coupling / Cap / Plug /Bushing / reducer / lap joint stub ends
Grade	304, 304L, 316, 316L, 2205, 2507
Standards	ASTM A403 / ASME B16.9. B16.11, MMS-SP-79,MSS-SP-83, MMS-SP-95, MMS-SP-97

Chemical Composition & Mechanical Properties

Here is a detailed table listing the common materials covered under ASTM A403/A403M, including their chemical composition and mechanical properties:

UNS	C	Mn	P	S	Si	Cr	Ni	Mo	N	Others
S30400	0.08	2	0.045	0.03	1	18.0-20.0	8.0-10.5	–	–	–
S30403	0.03	2	0.045	0.03	1	18.0-20.0	8.0-12.0	–	–	–
S30409	0.04-0.10	2	0.045	0.03	1	18.0-20.0	8.0-10.5	–	–	–
S31600	0.08	2	0.045	0.03	1	16.0-18.0	10.0-14.0	2.0-3.0	–	–
S31603	0.03	2	0.045	0.03	1	16.0-18.0	10.0-14.0	2.0-3.0	–	–
S31609	0.04-0.10	2	0.045	0.03	1	16.0-18.0	10.0-14.0	2.0-3.0	–	–
S32100	0.08	2	0.045	0.03	1	17.0-19.0	9.0-12.0	–	–	Ti ≥ 5*C, ≤ 0.70
S32109	0.04-0.10	2	0.045	0.03	1	17.0-19.0	9.0-12.0	–	–	Ti ≥ 4*C, ≤ 0.70
S34700	0.08	2	0.045	0.03	1	17.0-19.0	9.0-13.0	–	–	Nb + Ta ≥ 10*C, ≤ 1.0
S34709	0.04-0.10	2	0.045	0.03	1	17.0-19.0	9.0-13.0	–	–	Nb + Ta ≥ 8*C, ≤ 1.0
S31803/ S32205	0.03	2	0.03	0.02	1	22.0-23.0	4.5-6.5	3.0-3.5	0.14-0.20	–

The mechanical properties of each grade also differ:

UNS	Tensile Strength (MPa)	Yield Strength (MPa)	Elongation (%)	Hardness (HBW)
S30400	515 min	205 min	35 min	201 max
S30403	485 min	170 min	35 min	183 max
S30409	515 min	205 min	35 min	201 max
S31600	515 min	205 min	35 min	217 max
S31603	485 min	170 min	35 min	183 max
S31609	515 min	205 min	35 min	217 max
S32100	515 min	205 min	35 min	217 max
S32109	515 min	205 min	35 min	217 max
S34700	515 min	205 min	35 min	217 max
S34709	515 min	205 min	35 min	217 max
S31803/ S32205	620 min	450 min	25 min	293 max

Notes:
The chemical composition values are maximum limits unless a range is specified.
Mechanical properties such as tensile strength, yield strength, elongation, and hardness are typical minimum values required by the specification.
Different grades are chosen based on the specific requirements of corrosion resistance, mechanical strength, and suitability for various environments and temperatures.

Advantages and Disadvantages of ASTM A403

ASTM A234 pipe fittings offer numerous advantages, including high strength, durability, and versatility, but they also come with some disadvantages such as higher cost, complex manufacturing processes, and potential weight concerns. The selection of these fittings should consider the specific requirements and constraints of the application.

Advantages:

Emphasized high mechanical strength, making it suitable for high-pressure applications.
Suitable for both high and low-temperature environments, offering versatility for different service conditions.
Good weldability, particularly beneficial for complex piping systems that require on-site welding.

Disadvantages:

The initial cost of ASTM A234 fittings can be high due to the high-quality materials and stringent manufacturing processes.
While some grades of ASTM A234 fittings have good corrosion resistance, others may require additional protective coatings or treatments to prevent corrosion in harsh environments.

Applications of ASTM A403 Pipe Fittings

Petrochemical Industry
Oil and Gas Refining
Power Generation
Shipbuilding and Marine Engineering
Construction and Infrastructure
Chemical Processing
Pulp and Paper Industry
Food and Beverage Industry
Mining and Mineral Processing
Pharmaceutical Industry

Comparison of ASTM A403 and ASTM A815 Pipe Fittings

This table summarizes the key differences and similarities between ASTM A234 and ASTM A420 pipe fittings, highlighting their applications, material properties, and manufacturing processes.

Feature	ASTM A234	ASTM A420
Material and Application	Carbon and alloy steel	Carbon and alloy steel for low-temperature service
Typical Applications	High-temperature and high-pressure applications	Low-temperature applications
Industries	Oil and gas, petrochemical, power generation, chemical processing	Cold environments, LNG processing
Temperature Range	Above -29°C (-20°F)	Down to -50°C (-58°F) and lower
Mechanical Properties	High mechanical strength, suitable for high-pressure	Good mechanical strength, enhanced low-temperature toughness
Chemical Composition	Higher carbon content, includes manganese, chromium, molybdenum	Lower carbon content, may include nickel for impact resistance
Manufacturing Processes	Forging, hammering, normalizing, quenching, tempering	Similar processes, focused on low-temperature toughness
Heat Treatment	Achieves properties for high-temperature applications	Normalizing and tempering for low-temperature impact resistance
Standards Compliance	ASTM A234	ASTM A420
Common Grades	WPB, WPC, WP1, WP11, WP22, WP91	WPL6, WPL3, WPL8