Brief introduction to common problems and causes of PVC profiles

- Nov 08, 2019-

Profiles will encounter various problems during the processing. The summary is nothing more than: 1. excessive plasticization, 2. poor plasticization, 3. machine jam, 4. foreign matter, 5. uneven cooling, 6. traction speed There are many reasons for extension and expansion, and specific analysis is needed when encountering specific problems:


First, the surface is discolored and yellow:


Insufficient formulation stability, compatibility of stabilizers and lubricants is not appropriate, or the quality of small materials in the formulation is unqualified


Mixing temperature is too high or the barrel and head temperature are too high




Second, the profile warps or bends:


Uneven cooling, or too fast extrusion


The sizing die, the tractor, and the nose are not in a straight line.




Third, the surface is scratched:


Shaped mold or die has foreign matter




Fourth, the surface is rough, the gloss is poor, there is a cloud phenomenon:


Poor plasticization, low temperature or too fast extrusion or low ACR or poor quality




5. Yellow or black lines appear on the surface of the profile:


   1. There is a stagnant material in the joint core or in the mold




Sixth, the profile has obvious weld lines or cracks:


Poor plasticization or excessive lubrication in the formulation


Cooling water enters the cavity




Seven, the profile is brittle:


Poor plasticization,


Excessive lubrication or excessive or insufficient stabilizer


The impact modifier is too small or the quality is not good.




Eight, the cost is too high, the quality is not good:


Formula compatibility is not appropriate


Small material quality problem