ASTM · ASTM A234 M / ASME SA234 M

ASTM A234 / ASME SA 234 Pipe Fittings: Technical Specifications and Quality Standards

ASTM/ASME A/SA 234 Technical Standards: Scope

The ASTM A234 / ASME SA 234 specification regulates the requirements for piping fittings (elbows, tees, reducers, caps) manufactured from wrought carbon and alloy steels. Products supplied by EV Group China fully comply with the current editions of international standards ASME B16.9, ASME B16.11, MSS-SP-79, MSS-SP-83, MSS-SP-95, and MSS-SP-97, ensuring reliability in seamless and welded piping systems.

Geometric parameters of A234 / SA234 fittings from EV Group China:
Nominal Pipe Size (NPS): from 1/2" to 48" (range 21.3–1219.2 mm).
Wall thickness: from 2.77 mm to 59.51 mm.

These fittings are designed for operation under high pressure and elevated temperature conditions. They are an optimal solution for industrial piping systems and pressure vessels. For items outside the dimensional standards of ASME and MSS, additional requirements of the A960 / A960M specification (paragraph S58) shall apply.

This specification does not cover cast fittings. Fittings produced by casting must comply with standards A216/A216M or A217/A217M.

Documentation and technical data are presented in two measurement systems: inch-pound and SI. Each system shall be used independently to avoid engineering inconsistencies.

Material Execution

The raw materials used for production include forgings, bars, plates, and seamless or welded tubular products. The chemical composition of each heat is strictly controlled in accordance with industry tables. The use of deoxidizers and additives for grain size control is permitted within technological norms, while the introduction of non-regulated alloying elements is prohibited.

Manufacturing Technology

The production process includes forging, pressing, hot/cold rolling, extrusion, bending, as well as fusion welding and machining. The EV Group China technological cycle is tuned to exclude any structural damage to the metal during the forming process.

Chemical Composition of ASTM A234 / A234M Steel Grades

Steel Grade		WPB	WPC	WP1	WP12 CL1	WP12 CL2	WP11 CL1	WP11 CL2	WP22 CL1	WP5 CL1	WP91
Chemical Composition, %	C	0.30	0.35	0.28	0.05-0.20	0.05-0.20	0.05-0.15	0.05-0.20	0.05-0.15	0.15	0.08-0.12
Chemical Composition, %	Mn	0.29-1.06	0.29-1.06	0.30-0.90	0.30-0.80	0.30-0.80	0.30-0.60	0.30-0.80	0.30-0.60	0.30-0.60	0.30-0.60
Chemical Composition, %	P	0.050	0.050	0.045	0.045	0.045	0.030	0.040	0.040	0.040	0.020
Chemical Composition, %	S	0.058	0.058	0.045	0.045	0.045	0.030	0.040	0.040	0.030	0.010
Chemical Composition, %	Si	0.10 min.	0.10 min.	0.10-0.50	0.60	0.60	0.50-1.00	0.50-1.00	0.50	0.50	0.20-0.50
Chemical Composition, %	Cr	0.40	0.40	-	0.80-1.25	0.80-1.25	1.00-1.50	1.00-1.50	1.90-2.60	4.0-6.0	8.0-9.5
Chemical Composition, %	Mo	0.15 max.	0.15 max.	0.44-0.65	0.44-0.65	0.44-0.65	0.44-0.65	0.44-0.65	0.87-1.13	0.44-0.65	0.85-1.05
Chemical Composition, %	Ni	0.40	0.40	-	-	-	-	-	-	-	0.40
Chemical Composition, %	Cu	0.40	0.40	-	-	-	-	-	-	-	-
Chemical Composition, %	V	0.08	0.08	-	-	-	-	-	-	-	0.18-0.25
Chemical Composition, %	B	-	-	-	-	-	-	-	-	-	-
Chemical Composition, %	Others	-	-	-	-	-	-	-	-	-	Al 0.02

Note: For welded constructions, the "W" index is added to the grade designation. Total content of Cu, Ni, Cr, Mo impurities is limited to 1.00%.

Mechanical Properties of ASTM A234 / ASME SA 234 Fittings

Steel Grade	WPB	WPC	WP11 CL3	WP91
Min. Tensile Strength, ksi [MPa]	60-85 [415-585]	70-95 [485-655]	75-100 [520-690]	90 [620]
Min. Yield Strength, ksi [MPa]	35 [240]	40 [275]	45 [310]	60 [415]
Elongation (longitudinal), %	22	22	22	20
Elongation (transverse), %	14	14	14	13