90 degree steel pipe elbow types
90 degree steel pipe elbow changes fluid direction. It is the most used type in all the pipeline systems because it’s easy to compatible with the steel construction and structural. 90 degree reducing elbow can be used in connect pipes and fittings in different diameters.
90 Degree Pipe Elbow Connection
Considering the connection method, it has three types of 90 degree butt weld elbow, 90 degree socket weld elbow and 90 degree threaded elbow.
Ni alloy Incoloy800 elbows
Butt Weld Elbow
Butt weld 90 degree pipe elbow is the most common type. While using, you should align its end face with pipe or fittings, then heating up. In welding, several contact points should be established first. It can either be automated or done by hand. The fatigue resistance of manual BW welding is relatively poor, it is easy to cause defects such as overlap and undercut.
Features of Butt Weld Elbow
It has large size and schedule range.
Its weld seam has strong strength, and the stress is good. So the connection is strong and the leak proof is well.
It is wild used in high pressure and temperature piping system, some small diameter piping with low pressure also can be used.
It requires professional person to welding.
Welding detection requirements are high and tough.
90 degree A234 WPB elbow and 90 degree SS316 elbow are more common in the industries.
Socket weld ASTM A105 45 degree elbows
Socket Weld Elbow
The usage of socket weld 90 degree pipe elbow is insert the pipe into its socket for welding. The shape of its joint is similar to that of threaded elbow after forming.
Features of Socket Weld Elbow
It is economical in the application of small diameter pipe system with low pressure. The wall thickness of small diameter pipe is relatively thin, so it is difficult to butt welding.
Welding is relatively simple. It has no bother of beveling and misalign. The welding position can be adjusted to horizon.
Its diameter is a little bigger than pipes or fittings for the purpose of insert.
ASTM A105 elbow and A182 F316 elbow are popular material grade.
Stainless steel forged threaded elbow A182 F316 90 degree
Threaded Elbow
It is a widely used and removable elbow. They are often found in low-cost, noncritical applications. It is similar with socket weld elbow in size range and pressure rating, because both they are standardized by ASME B16.11 and BS3799.
Features of Threaded Elbow
Simple structure, and convenient installation and disassembly.
Simple and safe to operation. Its installation does not require professionals, open fire or electrical devices.
It is used in small diameter, low pressure and stable pipelines.
Go/no go gauge is convenient to check the threads.
Compared to SW and BW Pipe Elbow, its usage is more flexible, the technical requirements are low.
Clients are always interested or buy 90 Degree Pipe Elbow with BW End, because it is the most stable kind in connection and wild range. But the others are irreplaceable. Anyway they all have advantages and defects, please buy or use according to the actual situation.