1. The production method can be divided into pushing, pressing, forging, casting, etc..

2. Makes the standard can be divided into standard, standard electric ship standard, standard, standard, American Standard, German standard, Japanese standard, Russian standard, etc..

3. According to its radius of curvature can be divided into: long radius elbow and short radius elbow. Long radius elbow refers to its radius of curvature is equal to 1.5 times the diameter of the pipe, that is, R=1.5D; short radius elbow refers to its radius of curvature is equal to the outside diameter of the pipe, that is, R=1.0D. (D is the diameter of the elbow, R is the radius of curvature).

4. If divided by the pressure level to about seventeen, and the American Standard pipe is the same, are: Sch5s, Sch10s, Sch10, Sch20, Sch30, Sch40s, STD, Sch40, Sch60, Sch80s, XS; Sch80, SCH100, Sch120, Sch140, Sch160, XXS; one of the most commonly used is STD and XS two.

5. According to different shapes and uses can be divided into: grooved elbow, sleeve type double elbow, elbow, elbow, flange bearing reducing elbow, elbow, elbow and seat stay teeth, stamping elbow, push bend, socket elbow, elbow, faucet elbow etc..