Elbow plays a very important role in the pressure piping system, not only in the pipeline system can make a change in the direction of the pipeline, but also to increase the flexibility of the pipeline, reduce the vibration of the pipeline, reduce the role of the pipeline binding, and can play a role in the thermal expansion, Elbow so the elbow is an important part of the pressure pipeline. The elbow is the most stress in the pipeline and is thus the most vulnerable part of the pipeline. Elbow in the pipeline to change the direction of the role of the pipeline.

According to the Angle division, common has 45 degree elbow, 90 degree elbow and so on, there are some unusual angle elbow such as 60 degrees elbow, because the pipeline needs different, elbow angle is also different.

According to the classification of materials, there are cast iron, stainless steel, alloy steel, malleable iron, carbon steel, non-ferrous metals and plastics. According to the way of connection with pipe, there are direct welding, flange connection, Hot melt connection, fused connection, Elbow threaded connection and socket connection, etc.

According to the production process division, there are welding elbow, stamping elbow, push elbow, casting elbow, etc.

According to the radius of curvature, there is a long radius elbow and a short radius elbow (the long RADIUS elbow is the outer diameter of the pipe whose curvature radius is equal to 1.5 times times; the short radius elbow refers to its radius of curvature equal to the outside diameter of the pipe.)

According to the different shape uses to divide, has the card sleeve type elbow, the double bearing elbow, the flange elbow, the reducer elbow, the seat elbow, the internal and external tooth elbow, the ramming elbow, pushes the elbow, the socket elbow, to the welding elbow, the inner silk elbow and so on.

The elbow is suitable for a pipe fitting at the turning point, he can be divided into seamless elbow and straight seam elbow according to the different welding way. In the pipe system used in all the pipe fittings, seamless elbow accounted for the largest proportion. In general, Elbow different forming processes are selected for different material or wall thickness elbows. At present, the manufacturers commonly used seamless elbow forming process has hot push, stamping, extrusion and so on.

Because the elbow has a good comprehensive performance, so it is widely used in chemical, construction, water supply, drainage, petroleum, heavy industry, refrigeration, sanitation, plumbing, fire, electricity, aerospace, shipbuilding and other basic projects.

Requires control of radius of curvature. For example, Elbow the radius length is 1.5D, the radius of curvature must be within the required tolerance range. Because most of these fittings are used for welding, in order to improve the welding quality, the end of the Cheng Chengpo mouth, leaving a certain angle, with a certain edge, this request is also relatively strict, the edge of the thickness, the angle of how much and the range of deviations are specified, Elbow geometric size than the pipe many items. The elbow surface quality and mechanical properties are basically the same as the pipe. For easy soldering, the steel material of the connected pipe is the same.

After the end of the elbow type, but also need the car mouth, the car mouth is to facilitate welding, elbow connection way to see the needs of the project and the use of flange connection, elbow at both ends with flange, to the construction site directly installed on it can be, Elbow flange connection is not only good sealing surface performance, and disassembly is very convenient, thread connection, is the wire buckle elbow, and wire buckle pipe fittings or other equipment, to the construction site directly installed on it can be, but the wire buckle elbow is generally small and low pressure elbow, using wire buckle connection,

Large-caliber high-pressure elbow is welded or flange connection method. The elbow is in the piping system and is used to change the pipe direction.