Extrusion & Post
2 views
Bending deformation of random copolymer polypropylene pipe special material extruded pipes (Variant: mass production scenario)
Problem Phenomenon
The pipe bends after extrusion, and the straightness is out of tolerance.
Bending deformation affects the installation and use of the pipe, and is especially prominent in the production of long pipes.
In particular, in continuous mass production, this problem is more prominent and needs key attention.
Cause Analysis
（1）The cooling of each side in the extrusion direction is uneven, and the shrinkage is inconsistent
（2）The haul-off device is not concentric with the die
（3）The cooling water tank is installed incorrectly or the water temperature is uneven
（4）The pipe wall thickness is uneven, resulting in different shrinkage in all directions
（5）Improper support after extrusion, and the pipe's own weight causes bending
（6）In continuous mass production, process parameter fluctuations or equipment status changes have aggravated this problem
Solution
（1）Check the cooling system to ensure uniform cooling of each side of the pipe
（2）Adjust the center line of the haul-off device to align with the center of the die
（3）Correct the position of the cooling water tank and control the water temperature uniformly
（4）Adjust the concentricity of the die and the mandrel to ensure uniform wall thickness
（5）Add pipe support rollers to reduce self-weight deformation
（6）And establish standardized work instructions, with special attention to parameter stability in continuous mass production
Key Takeaway
Pipe bending is caused by non-uniform cooling or eccentric haul-off, and needs to be solved from cooling uniformity and equipment alignment.
In different production scenarios, targeted preventive measures need to be taken.
Was this helpful?
0 people found this helpful
Thank you for your feedback!