A234 WPB grade pipe fittings : Elbows | Tee | Cross | Caps | Reducers » Stainless Steel & Alloy Steel Pipes | 2PE 3PE coated pipe | Pipe Fittings

A234 WPB is a grade specification for Buttweld Fittings manufactured from carbon steel and alloy steel. The term “WPB” stands for “wrought pressure vessel quality, grade B.” These fittings are used for pressure piping and for pressure vessel fabrication for service at moderate and elevated temperatures.

The ASTM A234 standard covers the following types of fittings:

Elbows (45°, 90°, and 180°)
Tees and Crosses
Reducers (concentric and eccentric)
Caps and Stub Ends
Special Fittings (made as per customer specifications)

The key characteristics of A234 WPB steel pipe fittings include:

Material Composition: They are made from carbon and alloy steel. The carbon steel may be further classified as per ASTM A 106 and ASTM A 53 or API 5L.
Resistance: They are resistant to moderate and high-temperature service, making them suitable for many industrial applications that require strength and resistance to stress.
Manufacturing Process: The manufacturing process of these pipe fittings involves shaping the material through a process of heating, then cooling. This process is known as “wrought” which means it’s forged or shaped.
Uses: They are used in various industrial applications including petrochemical, oil and gas, and power generation due to their strength, flexibility, and resistance to thermal and mechanical stress.

It’s important to note that these fittings must be matched with appropriate pipes in terms of material grade and dimensional specifications to ensure the integrity of the entire piping system. Also, while A234 WPB is a common material grade, other grades can be used based on the specific requirements of the application. ASTM A234 also includes other grades such as WP1, WP5, WP9, WP11, WP22, and more, each with different properties tailored to different applications.

When choosing a pipe fitting, it’s usually important to consider factors such as the material grade, pressure rating, temperature rating, and the application’s specific requirements.

W = WELDABLE / wrought

P = RELATED TO P NUMBER OF ALLOY MATERIAL

B = REFER TO MINIMUM YIELD OF MATERIAL

Chemical Composition (%) of ASTM A234/A234M fittings

Grade	Type	Chemical Composition (%)
Grade	Type	C	Si	S	P	Mn	Cr	Ni	Mo	Other	ób	ós	δ5
WPB	0.3	0.1min	0.058	0.05	0.29-1.06	0.4	0.4	0.15	V:0.06;Nb:0.02	415-585	240	22	197
WPC	0.35	0.1min	0.058	0.05	0.29-1.06	0.4	0.4	0.15	V:0.06;Nb:0.02	485-655	275	22	197
WP1	0.28	0.1-0.5	0.045	0.045	0.3-0.9			0.44-0.65		380-550	205	22	197
WP12 CL1	0.05-0.2	0.6	0.045	0.045	0.3-0.8	0.8-1.25		0.44-0.65		415-585	220	22	197
WP12 CL2	0.05-0.2	0.6	0.045	0.045	0.3-0.8	0.8-1.25		0.44-0.65		485-655	275	22	197
WP11 CL1	0.05-0.15	0.5-1	0.03	0.03	0.3-0.6	1-1.5		0.44-0.65		415-585	205	22	197
WP11 CL2	0.05-0.2	0.5-1	0.04	0.04	0.3-0.8	1-1.5		0.44-0.65		485-655	275	22	197
WP11 CL3	0.05-0.2	0.5-1	0.04	0.04	0.3-0.8	1-1.5		0.44-0.65		520-690	310	22	197
WP22 CL1	0.05-0.15	0.5	0.04	0.04	0.3-0.6	1.9-2.6		0.87-1.13		415-585	205	22	197
WP22 CL3	0.05-0.15	0.5	0.04	0.04	0.3-0.6	1.9-2.6		0.87-1.13		520-690	310	22	197
WP5 CL1	0.15	0.5	0.03	0.04	0.3-0.6	4-6		0.44-0.65		415-585	205	22	217
WP5 CL3	0.15	0.5	0.03	0.04	0.3-0.6	4-6		0.44-0.65		520-690	310	22	217
WP9 CL1	0.15	1	0.03	0.03	0.3-0.6	8-10		0.9-1.1		415-585	205	22	217
WP9 CL3	0.15	1	0.03	0.03	0.3-0.6	8-10		0.9-1.1		520-690	310	22	217
WPR	0.2		0.05	0.045	0.4-1.06		1.6-2.24			435-605	315	22/28	217
WP91	0.08-0.12	0.2-0.5	0.01	0.02	0.3-0.6	8-9.5	0.4	0.85-1.05	See sdandard	585-760	415	20	248
WP911	0.09-0.13	0.1-0.5	0.01	0.02	0.3-0.6	8.5-10.5	0.4	0.9-1.1	See sdandard	620-840	440	20	248

Notes:

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 A234

Tensile Requirements	WPB	WPC, WP11CL2	WP11CL1	WP11CL3
Tensile Strength, min, ksi[MPa]	60-85	70-95	60-85	75-100
(0.2% offset or 0.5% extension-under-load)	[415-585]	[485-655]	[415-585]	[520-690]
Yield Strength, min, ksi[MPa]	32	40	30	45
Yield Strength, min, ksi[MPa]	[240]	[275]	[205]	[310]