Butt weld elbow and their applications: ANSI B16.9 ELBOW ASTM A234 WPB

What is a Butt Weld (Buttweld) Fitting?

A butt weld elbow is a type of pipe fitting used to join two pieces of pipe or tubing at an angle of 90° or 45°. Elbows are commonly used in plumbing, piping and mechanical systems to allow for changing directions of flow in the piping system. They are also used to join two pieces of pipe of different sizes or materials.

A buttweld fitting is a weldable pipe fitting that allows for change of direction of flow, to branch off, reduce pipe size or attach auxiliary equipment. Forged Steel buttweld fittings are manufactured in accordance with ANSI / ASME B16.9.

Butt weld fittings are available as elbows, tees, caps, reducers and out lets (olets). These fittings are the most common type of welded pipe fittings and are specified by nominal pipe size and pipe schedule. Buttweld fittings use seamless or welded pipe as the starting material and are formed (through multiple processes) to get the shape of elbows, tees and reducers etc. Just as the pipe is sold from Schedule 10 to Schedule 160, butt weld pipe fittings are sold the same way. Welded butt weld fittings are more common in stainless steel due to cost advantage. Sch 10 fittings are also more common in stainless steel butt weld fittings.

Common material for butt weld fittings are A234 WPB (A & C also available), High Yield Carbon Steel, Stainless Steel 304 and 316 and Nickel Alloys.

Elbows are generally made from steel or stainless steel and come in several sizes, shapes and wall thicknesses. They are usually either welded or threaded and are available in different degrees ranging from 45° to 180°.

The most commonly used angles for elbows are 90° and 45°. A 90° elbow is used to change the direction of flow in a piping system by 90° while a 45° elbow is used to change the direction of flow in a piping system by 45°.

Butt weld elbows are widely used in many industrial applications such as in chemical plants, power plants, refineries, and food processing plants. They are used to connect two pipes of different diameters in order to regulate the flow of liquids and gases.

When choosing a butt weld elbow, it is important to consider the size, material, and wall thickness of the elbow. The size of the elbow should be compatible with the size of the pipe or tubing it will be connecting. The material of the elbow should also be compatible with the material of the pipe or tubing it will be connecting. The wall thickness of the elbow should also be taken into account, as it will affect the pressure rating of the elbow.

There are several different types of butt weld elbows available on the market, including long radius elbows, short radius elbows, and reducing elbows. Long radius elbows are used to change the direction of flow by 90° or 45° and have a curvature radius that is 1.5 times the pipe diameter. Short radius elbows are used to change the direction of flow by 90° or 45° and have a curvature radius that is 1.0 times the pipe diameter. Reducing elbows are used to join two pipes of different sizes, as the curvature radius is different for each end of the elbow.

Butt weld elbows are used in many industrial piping systems to regulate the flow of liquids and gases. They are available in different sizes, materials, and wall thicknesses, and can be used to connect two pipes of different diameters. When choosing a butt weld elbow, it is important to consider the size, material, and wall thickness of the elbow in order to ensure it is compatible with the pipe or tubing it will be connecting.

Elbow Type	Long radius elbow,Short radius elbow, 90 degree elbow, 45 degree elbow,180 degree elbow, reducing elbow.
Standard	ASME B16.9, ASME B16.11, ASME B16.5; JIS B2311,JIS B2312,JIS B2313,JIS B2316; MSS SP-43, MSS SP-95, MSS SP-75, MSS SP-79; ISO 3419,ISO 5251,DIN 2615 SY/T 0510, SH 3408, SH3410
Size	1/2”-48”(Butt-welding and seamless);1/8”-4”(Threaded and socket-welding);  16”~72”(Welded)
Wall thickness	SCH10,SCH20,SCH30,STD,SCH40,SCH60,XS,SCH100,SCH120,SCH40,SCH160,XXS
Manufacturing process	Hot forming, Push, Press, Forge, Cast, etc.
Material       Carbon steel     Stainless steel   Alloy steel   Duplex steel   Nickel alloy steel	Carbon steel elbow, stainless steel elbow, alloy steel elbow
	ASTM A234 WPB, ASTM A420 WPL6, WPL3; ASTM A105 WPB; ASTM A106; ASTM A350 LF2, DIN St37, St45.8, St52.4,St.35.8,St.35.8/I ASTM A333 GR.6, ASTM A860 WPHY 70, WPHY 65, WPHY 60, WPHY 52,WPHY 46,WPHY 42, API 5L GRB, X60, X65, X42,X52,
	ASTM A403 WP304, A403 WP304L, A403 WP316, A403 WP316L, A403 WP321 ASTM A182 F 304, 304L,316, 316L,904L
	ASTM A234 WP12, A234 WP11, A234 WP22, A234 WP5, A234 WP9 A420 WPL8, A420 WPL9 ASTM A335 P5, P9, P11, P12, P22, P91 ASTM A213 ASTM A182 F5,F11,F22,F91
	ASTM A182 F51/SAF 2205/S31803,F53/SAF 2507/S32750,F60/UNS S32205,
	Alloy 200/nickel 200/UNS S2200,Alloy 400/monel 400/UNS 4400,Alloy 600/Inconel 600/UNS 6600,Alloy 201/nickel 201/UNS S2201,Alloy 625/Inconel 625/UNS 6625/NS336,Alloy 800/Incoloy 800/UNS S8800.

 

 

 

 

ASTM A234 WP91 PIPE FITTINGS CHEMICAL COMPOSITION

Grade	C	Mn	P	S	Si	Cr	Mo
A234 WP91	0.08-0.12	0.3-0.6	≤0.015	≤0.02	0.2-0.5	8-9.5	0.85-1.05

ASTM A234 WP91 PIPE FITTINGS MECHANICAL PROPERTIES

Element	Tensile Strength	Yield Strength (0.2%Offset)	Elongation
A234 WP91	≥590	≥415	≥20

Material:
Alloy Steel: ASTM A234 / WP5/ WP9/ WP11/ WP22/ WP91