Common problems with anti-shrink molds

The wrinkle prevention mold (also known as wrinkle prevention block, wrinkle prevention plate or wrinkle prevention mold) is a key part of the bending process, mainly used to prevent the pipe from being pressed on the inside during the bending process to produce wrinkles, dents or section deformation.

  1. The function of wrinkle-proof mold

Prevent wrinkling of the tube wall: when bending, the inner side of the tube is under pressure and prone to wrinkling. The wrinkle prevention mold disperses the pressure by supporting the tube wall.

Keep the section shape: avoid flattening or ellipticalizing the pipe to ensure dimensional accuracy after bending.

Improve surface quality: reduce scratches and dents caused by friction or compression.

  1. Installation and debugging

Positioning calibration: The anti-wrinkle mold should be aligned with the centerline of the bending mold; any deviation can lead to uneven force distribution.

Clearance adjustment: The clearance between the mold and the pipe is typically 10% to 20% of the pipe wall thickness, which requires fine-tuning through trial bending.

Pressure testing: Start with a low-speed trial bend to observe the wrinkles, then gradually optimize the parameters.

  1. Common problems and solutions

Question 1: There are still wrinkles on the inside after bending. Possible reasons: insufficient pressure of anti-wrinkle mold, wear or material mismatch. Solution: increase pressure, replace wear-resistant materials or check the alignment of the mold.

Problem 2: Surface scratches on the pipe → Possible causes: high roughness of the anti-wrinkle mold or insufficient lubrication. → Solutions: polish the surface of the mold, add lubricant or change to a soft anti-wrinkle mold.

Question 3: Short life of anti-wrinkle mold → Possible reasons: insufficient material hardness or too fast bending speed. → Solution: upgrade to hard alloy mold and reduce bending speed.

  1. Maintenance recommendations

Regular cleaning: remove metal chips and oil stains to avoid scratches on the pipe.

Lubrication maintenance: apply high temperature grease to the sliding parts to reduce wear.

Check for wear: pay special attention to the grooves or scratches on the contact surface and repair or replace them in time.

By reasonably selecting, installing and maintaining the wrinkle prevention mold, the quality and efficiency of bending can be significantly improved. In practical application, it is necessary to optimize the characteristics of pipe materials (material, wall thickness, diameter) and process requirements (bending Angle, radius).

The above content is transcribed by the editor of Shenglida Technology (Zhangjiagang) Co., LTD