How to restrain the spring back after the clamp release

We have learned about the spring back of pipe of mandrel pipe bending machine before. That spring back is dominated by the material properties of pipe fitting itself, which can be corrected by the program settings on the machine. And there is also a kind of rebound which is both dominated by material properties and caused by post-processing, which is the deformation of the pipe. This deformation is produced by the pipe fitting in order to release the binding force, just like a spring will spring up when it is released after pressing down. This problem often occurs between the first bending of the pipe and the transition to the next bending position. When the clamping die guide is released, the bending stress at the front end and the extrusion force are released instantaneously, which will cause the pipe to escape from the groove, and the next clamping will have a high probability of clamping the pipe. How do we deal with this situation?

If you are using a CNC pipe bender, you can use the half-clip mode (Figure 1).

Figure 1 Clamping die half open

Use the clamping mode in the program. As shown in the picture, he will only loosen a certain gap on the pipe, and the clamping mold will not be completely opened. In this way, it can not only meet the normal push pipe fitting, but also prevent the pipe fitting from falling off after the claw is released. In this way, the pipe fittings with requirements for appearance also reduce the probability of surface wear.

If you use NC pipe bender, your pipes need manual participation in clamping and positioning, and the system itself does not have the setting of clamping die half-open. Shorter pipes are easier to handle, while longer pipes cannot be completed by a single operator. Therefore, it is necessary to make a self-made pipe pressing device. The design concept of this device is that its own weight will press the pipe into the groove of the mold, and the pipe will not fall even if the mold is released. The pipes can move under the device when the manual is applied with less force.

Using the different methods of the above two models can perfectly solve the phenomenon of pipe fitting spring back and demold. I hope this article will be helpful for your use.