Pipe Elbow Classification

Pipe Elbow Classification

In the pipeline system, elbow is a pipe fitting that changes the direction of the pipeline. According to the angle, there are three most commonly used elbows: 45°, 90° and 180°. In addition, according to project needs, other abnormal angle elbows such as 60° are also included. Elbow materials include cast iron, stainless steel, alloy steel, malleable cast iron, carbon steel, non-ferrous metals and plastics, etc.

    

According to the standards:

American National Standards

ASME B16.25 Wrought

ASME/ANSI B16.28  Wrought Steel Butt-welding Short Radius Elbows and Returns

Wrought High-Strength Low-Alloy Steel Butt-Welding Fittings

German national standards :

DIN 2605  Steel Butt-welding Pipe Fittings:Elbows And Bends

Japanese Industrial Standards:

JIS B2311 / JIS B2312 steel butt-welding pipe fittings for ordinary use

Russia Industrial Standards:

GOST 17375 Carbon And Low-alloy Steel Butt-welding Fittings - Sharply Curved Bends Type 3d (r=1,5 Dn) - Design

 GOST 30753 Carbon And Low-alloy Steel Butt-welding Fittings - Sharply Curved Bends Type 2d (r=dn) - Design

According to the material:

●Carbon steel elbows  ASTM/ASME A234 WPB、WPC

●Alloy steel elbows ASTM/ASME A234 WP

●Stainless steel elbows ASTM/ASME A403 WP  

●Cast iron elbows

●Copper elbows......
 

According to the curvature radius:

●SR (Short Radius) Elbows:

These elbows have a Center-to-Face dimension of 1.0 X diameter. They are typically used in tight areas where clearance is the main issue.

●LR (Long Radius) Elbows:

These elbows have a Center-to-Face dimension of 1.5 X diameter. They are the most common type of elbow and used when space is available and flow is more critical.

According to the pressure classes:

2000 # Class: Applicable for Screwed fittings only, Thickness-SCH 80 or XS

3000 # Class: Socket weld fittings, Thickness-SCH 80 or XS & Screwed fittings, Thickness-SCH 160

6000 # Class: Socket weld fittings, Thickness-SCH 160 & Screwed fittings, Thickness-SCH XXS

9000 # Class: Applicable for Socket weld fittings only, Thickness-SCH X XS

According to the manufacture process:

Push manufacturing ,Press manufacturing ,Forge manufacturing,Cast manufacturing 

According to the shapes and threaded type:

Grooved elbow, sleeve type double elbow,flange bearing reducing elbow,Reducing elbow, stamping elbow, push bend elbow, socket elbow, butt weld elbow, faucet elbow etc..