A350 Carbon Steel Elbow

Product Specification

90 Seamless Elbow A350 LF2 Low Temperature Resistant Carbon Steel Pipe Fittings Elbow

Pushing elbow is one of the forming processes of elbows. The elbow is used at the turn of pipes or pipe fittings and is used to change the direction of the pipe. The geometric dimensions of the push elbow include outer diameter, inner diameter, and wall thickness. . It is also required to control the radius of curvature. For example, if the radius length is 1.5D, the radius of curvature must be within the required tolerance range. Generally, the connection method of elbows is mostly welding, and there are also some connection methods such as flange connection. The most common method is welding connection. Since most push elbows need welding, in order to improve the quality of welding, it is also convenient for welding. Simple, good welding quality, the ends are all beveled, the elbow port has a certain angle, with a certain edge, this requirement is also strict, the thickness of the edge, the angle and the deviation range are all specified , There are many more items in geometric size than push elbow.

The surface quality and mechanical properties are basically the same as the pipe.

For the convenience of welding, the steel grade is the same as that of the connected pipe. All push elbows must undergo surface treatment, and the oxide scale on the inner and outer surfaces is sprayed off by shot blasting, and then coated with anticorrosive paint. This is for export needs. Moreover, it is also for the convenience of transportation in the country to prevent corrosion and oxidation. This work must be done. It is the packaging requirements. For small pipe fittings, such as export, wooden boxes are required, about 1 cubic meter, and the number of elbows in this box cannot exceed one ton. This standard allows sets, that is, large sets of small, but total The weight should generally not exceed 1 ton. For large items, it must be packaged individually, such as 24″ must be packaged individually. The other is the packaging mark, which must indicate the size, steel number, batch number, and manufacturer’s trademark. The steel stamp should be stamped on the push elbow and attached Documents such as packing list and warranty.

The process parameters that affect the geometry of the push elbow are: the material, wall thickness and outer diameter of the push blank, the material and shape of the mandrel head, the heating temperature and its distribution, and the advancing speed. The influence of each process parameter on the geometry of the push elbow is discussed below. (1) The influence of the material, wall thickness and outer diameter of the blank for the push elbow on the geometry of the push elbow. The commonly used materials for the push elbow in the thermal power industry include WB36 and A335P22. The high temperature strength of WB36 is less than that of A335P22, the high temperature plasticity of WB36 is less than that of A335P22, and the thermal conductivity of WB36 is less than that of A335P22. Therefore, when the blank outer diameter, wall thickness and mandrel head shape and size are the same, the bonding performance of WB36 and mold is less than that of A335P22. Pushing the elbow requires normalizing + tempering heat treatment, machined ports, and the wall thickness needs to be left with burning damage and machining allowance. The general margin is 10% to 20% of the theoretical wall thickness of the elbow. The smaller the ratio of the wall thickness δ of the elbow to the cross-sectional diameter D, the better the adhesion to the mold, but the more easily the inner arc of the elbow becomes unstable and wrinkles. According to the characteristics that the volume of metal does not change during plastic deformation, the wall thickness does not change during forming (actually slightly thinned), and the length of the outer arc of the elbow is equal to the length of the tube blank, the formula for the outer diameter of the tube blank is derived: Dp — ——The outer diameter of the tube blank; R————The curvature radius of the elbow;
δ———Wall thickness of elbow;
D———The diameter of the elbow section.

use
A commonly used connection pipe fitting in pipeline installation, connecting two pipes with the same or different nominal diameters, so that the pipeline can be turned at a certain angle.