The inner wrinkling of tube bending machine when bending

When the tube bending machine with mandrel is working, the inner of material maybe wrinkling if the machine don’t equipped with a mandrel.

So, a suitable mandrel (chain mandrel) is the first step to solve this problem.

The inner material is in the extrusion state during the bending process, the pipe always has the tendency of wrinkling. Even with a mandrel to support the material, but there will still wrinkling. Under this condition, wrinkle plate can be considered.

What is the anti-wrinkle plate?

It is installed on one side of the forming mold of tube binding machine. The inner dimension of the anti-wrinkle plate is the outer diameter of the pipe. And the leading edge is close to the molding mold. It is just like a scraper, scraping all parts of the inside of the pipe passing through during the bending process, and reduces the tendency of pipe wrinkling. So, no matter where the scraper starts to scrape, the angle between the scraper and the pipe will have an impact on the pipe forming.

When the pipe is wrinkled,the order of suitable processing is (with mandrel use):

1. Add anti-wrinkle mold in the machine.

2. If the anti-wrinkle plate is added, there are still wrinkles , bring the leading edge of the anti-wrinkle plate closer to the cutting point of the forming die.

3. Reduce the inclination angle of the anti-wrinkle plate if the best effect is not achieved.

4. Consider whether the mold material should be replaced if the effect of the pipe is still not good.

If there are many small wrinkles, they are distributed in everywhere. We have checked the position of the anti-wrinkle plate and the mandrel, and found that there is no problem with the position and angle. How we solve this?

1. Check whether the mandrel size is too small

2. Increase the pressure of the die after checked the position of the anti-wrinkle plate and the mandrel

3. Reduce the advance boost of pressure die.

As we can know, the real reason that affects the wrinkle is how to control the position between materials during bending process. The pressure die and pressure die boost is the most influential factor on materials transformation. The purposes of increase the pressure of pressure dies and reduce advance boost are to reduce the forward trend of materials. This effect cooperated with mandrel and anti-wrinkle plate can produce pipe with good quality.

If you want to know more about skills of bending pipe, you can see our blog “common deficiencies and solutions of pipe bender”, we can also provide guidance on safe operation of pipe bender to you. We will let you know more about pipe bender while purchasing tube bending machine for sale.