Pipe elbows
Pipe elbows are versatile pipe fittings used to make turns in piping systems, available in various angles and materials.
ASTM A234/A234M Standard Specification for Piping Fittings of Wrought Carbon Steel and Alloy Steel for Moderate and High Temperature Service.
ASTM A234/A234M specification covers wrought carbon steel and alloy steel fittings of seamless and welded construction. These fittings are for use in pressure piping and in pressure vessel fabrication for service at moderate and elevated temperatures. The material for fittings shall consist of killed steel, forgings, bars, plates, seamless or fusion-welded tubular products with filler metal added. Forging or shaping operations may be performed by hammering, pressing, piercing, extruding, upsetting, rolling, bending, fusion welding, machining, or by a combination of two or more of these operations. The forming procedure shall be so applied that it will not produce injurious imperfections in the fittings. Fittings, after forming at an elevated temperature, shall be cooled to a temperature below the critical range under suitable conditions to prevent injurious defects caused by too rapid cooling, but in no case more rapidly than the cooling rate in still air. The fittings shall be subjected to tension test, hardness test, and hydrostatic test.
A234 WPB steel pipe fittings mean the pipe fitting which material is ASTM A234 WPB,they are used for the pressure piping systems of moderate and high temperature services.ASTM A234 is the standard of pipe fittings material,it indicates the materials properties of different kinds of carbon steel and alloy steel,WPB is one of the steel grade in this standard.W means weldable,P means pressure,B is grade b,refer to the minimum yield strength,like the astm A106 A53,Gr.B or API 5L Gr.B.A234 WPB is the most common carbon steel pipe fittings material.
W = WELDABLE / wrought
P = RELATED TO P NUMBER OF ALLOY MATERIAL
B = REFER TO MINIMUM YIELD OF MATERIAL
The WPB is not short hand for any process. It is simply an identifier developed by ASTM. The fittings in question are manufactured in the same manner as the companion pipe for this specification.
In very large sizes, the fittings may be manufactured in pieces and welded together as is the case for many large fittings.
The term used for the manufacturing is called “wrought” which means it is worked as opposed to being cast or forged.
As to the W standing for weldable, I’m not sure that is correct since that are many, many pipe fittings that are weldable but carry designations other than a W. Note the reference below.
Standard Specification for Piping Fittings of Wrought Carbon Steel and Alloy Steel for Moderate and High Temperature Service
This standard covers wrought carbon steel fittings of seamless and welded construction which are manufactured to the dimensional specifications of ASME B16.9 and B16.28. These fittings are primarily for use in pressure piping and in pressure vessel fabrication for service at moderate and elevated temperatures.
ASTM A234/A234M is a standard specification for piping fittings of wrought carbon steel and alloy steel for moderate and high-temperature service. This specification covers several grades of fittings that are used in various applications in the oil and gas, petrochemical, and power generation industries.
Download PDF| 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 |
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.
| Tensile Requirements | WPB | WPC, WP11CL2 | WP11CL1 | WP11CL3 |
|---|---|---|---|---|
| Tensile Strength, min, ksi[MPa] (0.2% offset or 0.5% extension-under-load) |
60-85 [415-585] |
70-95 [485-655] |
60-85 [415-585] |
75-100 [520-690] |
| Yield Strength, min, ksi[MPa] | 32 [240] |
40 [275] |
30 [205] |
45 [310] |
Ceramic lined pipe is made through self-propagating high-temperature synthesis (SHS) technique.
Cast basalt lined steel pipe is composed by lined with cast basalt pipe, outside steel pipe and cement mortar filling between the two layers.
Ceramic tile lined pipes have very uniform coating of specially formulated ceramic material that is affixed to the inner of the pipe.
The material of the rare earth alloy wear-resistant pipe is ZG40CrMnMoNiSiRe, which is also the grade of rare earth alloy steel.
Tubes Erosion Shields are used to protect boiler tubing from the highly erosive effects of high temperatures and pressures thereby greatly extending tube life.
The ASTM A213 T91 seamless tubes are primarily used for boiler, superheater, and heat-exchanger.
