ASTM A815 pipe fittings are specifications for wrought austenitic, ferritic, duplex stainless steel butt-welded fittings. These fittings are designed for use in high-pressure, high-temperature, and corrosive environments, making them suitable for a wide range of industries, including oil and gas, chemical processing, petrochemical, and more.  Duplex stainless steels are characterized by their mixed microstructure of austenite and ferrite phases, which gives them enhanced mechanical properties and corrosion resistance compared to traditional austenitic stainless steels.

The ASTM A815 standard provides specifications for various types of butt weld fittings, including elbows, tees, reducers, caps, crosses, and more. These fittings are produced in a range of sizes and dimensions to meet the diverse needs of different industries and applications.

ASTM A815 Pipe Fittings Specification

Size Range	1/2″ – 80″ / DN15 – 2000
Thickness Schedule	SCH 10, 20, 40, STD, XS, 80, 100, 120, 140, 160, XXS
Standard	ANSI / ASME B16.9, MSS SP 43, JIS B2311/2312/2313, EN10253
Duplex Stainless Steel Grades	ASTM A815 S32205, S31803, 32750, 32760

ASTM A815 Standard Scope

This specification covers two general classes, WP and CR, of wrought ferritic, ferritic/austenitic, and martensitic stainless steel fittings of seamless and welded construction covered by the latest revision of Specification A960/A960M. Fittings differing from these standards may be furnished in accordance with Supplementary Requirement S58 of Specification A960/A960M.

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.

ASTM A815 Pipe Fittings Material

ASME A815 Duplex Steel Butt weld Fittings Equivalent Grades

STANDARD	WERKSTOFF NR.	UNS
UNS S32760	1.4462	S31803 / S32205

Chemical Composition of ASTM A815 Butt weld Fittings

Chromium is one of the most important alloying elements in ASTM A815 Pipe Fittings. It can form a dense oxide film (passivation film) on the surface of steel, thereby improving the corrosion resistance of steel.

Nickel is an austenite-forming element that can expand the austenite phase area and enable stainless steel to maintain an austenite structure at room temperature.

Molybdenum can significantly improve the resistance of stainless steel to pitting corrosion, crevice corrosion and stress corrosion cracking.

Nitrogen is an effective austenite-forming element and also increases the strength and corrosion resistance of stainless steel.

CHEMICAL	LIMITS	C	Mn	P	S	Si	Cr	Ni	Mo	N
ASTM A815 UNS 31803	MIN
	MAX	0.03	2.0	0.030	0.020	1.0	23	6.5	3.5	0.20
ASTM A815 UNS 32750	MIN						24.00	6.00	3.00	0.24
	MAX	0.03	1.20	0.04	0.02	0.80	26.00	8.00	5.00	0.32
ASTM A815 WPS 32760	MIN						24.00	6.00	3.00	0.20
	MAX	0.03	1.00	0.03	0.01	1.00	26.00	8.00	4.00	0.30
ASTM A815 WPS 32205	MIN						22.00	4.50	3.00	0.14
	MAX	0.03	2.00	0.03	0.02	1.00	23.00	6.50	3.50	0.20

Mechanical Properties of ASTM A815 Pipe Fittings

The two-phase structure of duplex stainless steel makes it stronger than ordinary austenitic stainless steel. This makes duplex stainless steel ASTM A815 pipe fittings perform well in high-pressure and high-load applications, such as in high-pressure pipeline systems in the fields of petrochemicals, natural gas transportation, etc., which can reduce pipeline wall thickness and reduce costs while ensuring the safe operation of the pipeline system.

MATERIAL	ASTM A815 UNS 31803	ASTM A815 WPS 32205	ASTM A815 WPS 32750	ASTM A815 WPS 32760
T.S (MPA)	620 min	655min	800min	750min
Y.S (MPA)	450 min	450min	550min	550min
EL %	20 min	20 min	15min	25min
HARDNESS	290 max	290 max	310min	270min

Physical Properties of ASTM A815 Pipe Fittings

Grades	Density (g/cm 3)	Density (lb/in 3)	Melting Point (°C)	Melting Point (°F)
S31803 / S32205	7.805	0.285	1420 – 1465	2588 – 2669

Performance characteristics

High strength: The two-phase structure of duplex stainless steel makes it have higher strength than ordinary austenitic stainless steel. This makes duplex stainless steel butt weld pipe fittings perform well in high-pressure and high-load application scenarios.

Good corrosion resistance: ASTM A815 pipe fittings has the corrosion resistance advantages of ferritic stainless steel and austenitic stainless steel, and has good resistance to a variety of corrosive media. In the chemical industry, it can resist the erosion of various acid and alkali media to ensure the safety and stability of chemical production.

Excellent welding performance: ASTM A815 Duplex stainless steel has good welding performance and is not prone to defects such as thermal cracks during welding. This is very important for the manufacture of butt-welded pipe fittings, which can ensure the welding quality and the overall performance of the pipe fittings.