Introduction to Bend Method
There are various methods for bending pipes, which can be divided into bending, pushing, pressing, and rolling according to different bending methods; According to whether the bending is heated or not, it can be divided into cold bending and hot bending; According to the presence or absence of core pulling during bending, it can be divided into cored (filled) bends and coreless (filled) bends. Here is a brief introduction to various methods: different bending methods
1) Detour
Bend bending is one of the most commonly used bending methods, which is divided into two categories: manual bending and power bending. Manual bending is the use of a simple bending device to bend and process pipes, usually small diameter (pipe outer diameter D ≤ 20mm) pipes. Due to the small bending torque, cold bending is used, while larger diameter pipes are mostly hot bending or hydraulic and electric driven bending. Manual bending does not require specialized bending equipment, as its bending device has low manufacturing costs, It is also convenient to adjust and use, so it is suitable for small batch production without dedicated bending equipment.
2) Push bending
Push bending
Generally, servo motors or hydraulic systems provide power to perform forced bending of pre bent pipes. The pre bending angle is determined by the required forming radius of the pipe, and then the moving trolley on the bed provides longitudinal compression force to the pipe. The pre bending roller position forces the pipe to form, which is a relatively new bending method. Especially when bending small curvature pipe fittings, this method is particularly advantageous, Not only can it save a lot of raw materials, but it can also avoid unexpected interference. As a relatively new bending method, its development is not yet mature, and there is no empirical formula to follow for the power required for pushing bending.
3) Compression bending
As one of the earliest methods used for pipe bending processing, bending was the simultaneous bending of pipe blanks using two straight section molds. This bending method can not only process pipes with straight sections, but also be used to bend elbows. Currently, bending is widely used to press elbows, which is already quite common in the process of pressing elbows.
4) Roll bending
Roll bending is a method of processing pipes under the rolling pressure of three driving rollers. The principle of roll bending is basically the same as that of bending machines and sheet metal, except that the rollers used for pipe rolling have a working surface that matches the cross-sectional shape of the bent pipe blank; By changing the spacing of the rollers, any curvature radius can be bent. The rolling bending method has certain limitations on the bending radius and is only suitable for thick walled pipe fittings with high curvature radius requirements, especially for bending circular or spiral curved pipe fittings.