Experts explain the important technical features of pipe bending machines

The pipe bending machine is mainly used for laying and repairing pipes in power construction, highway and railway construction, boilers, bridges, ships, furniture, decoration, etc. It has the advantages of multiple functions, reasonable structure, and simple operation. The basic working principle of the pipe bending machine is to apply bending moment through reasonable fulcrums and force points to make the steel pipe plastically deformed, thereby achieving the purpose of cold bending of the steel pipe. The lower die is located at the front of the pipe bending machine, and it is suspended on the frame by a hydraulic cylinder in a floating state. The steel pipe is introduced into the lower die from the rear of the pipe bending machine through the clamp and the upper die using a sling, and the inner tube is loaded into the steel pipe and placed in the center of the upper die. The inner tube expansion block is supported to support the inner wall of the steel pipe, so that the steel pipe can avoid abnormal deformation during the bending process. The following platform and experts will give several technical features to the majority of enterprises using pipe bending machines:

1. Regularization of pipe shape

When designing and arranging pipes, avoid excessive arcs, arbitrary curves, compound bends, and arcs greater than 180. An overly large arc not only makes the tooling bulky, but also is limited by the size of the pipe bending machine; the design of arbitrary curves and compound bends is very unreasonable, which greatly hinders mechanized and automated production and makes it difficult for operators to get rid of heavy physical labor; an arc greater than 180. makes it impossible for the pipe bending machine to unload the mold.

2. Standardization of bending radius

The bending radius should try to achieve "one tube one mold" and "multiple tubes one mold". For a pipe, no matter how many bends there are and what the bending angle is, there can only be one bending radius, because the pipe bending machine does not change the module during the bending process, which is "one tube one mold". And "multiple tubes one mold" means that pipes of the same diameter specification should try to use the same bending radius, that is, use the same set of modules to bend pipes of different shapes, which is conducive to reducing the number of modules.

3. Appropriate bending radius value

The size of the catheter bending radius determines the size of the resistance encountered by the catheter during bending. Generally speaking, when the pipe diameter is large and the bending radius is small, it is easy to wrinkle and slip when bending, and the bending quality is difficult to guarantee. Therefore, it is generally better to select the R value of the pipe bending die to be 2 to 3 times the pipe diameter.

4. Appropriate bending forming speed

The main influence of the bending forming speed on the forming quality is: if the speed is too fast, it is easy to cause the flatness of the bending part of the conduit, the roundness does not meet the requirements, and the conduit is pulled and broken; if the speed is too slow, it is easy to cause the wrinkling of the conduit and the slipping of the pressing block, and the large-diameter pipe is easy to form the sinking of the bending part of the conduit. According to a large number of tests on these two CNC pipe bending machines, the bending speed of the conduit is determined to be 20%-40% of the maximum bending speed of the machine.

5. Appropriate mandrel and its position

The mandrel mainly supports the inner wall of the bending radius of the conduit to prevent its deformation during the bending process. At present, if the mandrel is not used for bending and forming of domestic pipes on machine tools, its quality is difficult to guarantee. There are many forms of mandrels, such as column mandrels, universal single, double, triple, and quadruple ball mandrels, directional single and multi-ball mandrels, etc. In addition, the position of the mandrel also has a certain influence on the bending of the conduit: theoretically, its tangent should be flush with the tangent of the bending die, but after a large number of tests, it has been proved that it is better to advance 1 to 2 mm, and the bending quality is relatively ideal at this time. Of course, if the advance amount is too large, the outer wall of the bending part will appear the so-called "goose head" phenomenon.

Zhangjiagang Hehe Machinery Co., Ltd. is a Taiwanese investment enterprise. It specializes in the research and development and manufacturing of metal circular saw machines, CNC pipe bending machines, pipe end forming machines and other pipe machinery and equipment. In response to the needs of furniture, sports equipment, car driving, auto parts, air conditioning pipe industry, decorative materials and other industries, the company adheres to Taiwan's advanced technology to develop and manufacture metal circular saw machines, CNC pipe bending machines, pipe end forming machines and other pipe processing machinery and equipment. The company can also design and manufacture special specifications of models and various non-standard machinery and equipment according to customer needs.