Seamless and welded butt welded pipe fitting
The steel butt welded pipe fittings listed in the product standard include elbow, tee, tee, reducing pipe (also known as big or small head), pipe cap, elbow, flange nipple, branch socket, etc.
Commonly used elbow according to bending Angle is divided into 45° elbow, 90° elbow and 180° elbow;According to bending radius, it is divided into long radius bend (R≈ 1.5dn, i.e. bending radius is about 1.5 times of nominal diameter) and short radius bend (R≈ 1.0dn, i.e. bending radius is about 1 times of nominal diameter).Among them, 90° long radius elbow and reducing elbow.In addition, according to the needs of piping direction, there will be special Angle elbow, such as 60°, 88°25 "elbow.
Tee and tee are divided into equal diameter and reducing diameter. The nozzle ends of equal diameter tee and tee are of the same size.The pipe size of branch pipe is smaller than that of main pipe.
The reducing pipe has concentric and eccentric points, concentric reducing pipe big end diameter and small end diameter for the same axis;The large end diameter and the small end diameter of the eccentric reducing pipe are two parallel axes. One side of the small end diameter is parallel to the outer edge of the large end diameter.
Elbow according to the bending Angle and bending radius orders, general requirements at both ends of the elbow with straight pipe section, bending radius is usually the minimum of 2.5 ~ 3 times the outer diameter of the pipe (R≥ 2.5d ~ 3D).
The types of products covered by the standard for steel butt welded pipe fittings are listed below.
45 ° long radius
90 ° long radius
90 ° short radius
180 ° long radius
180 ° long radius
Reducing pipe (size head)