The problems often appeared in PVC profiles and the summaries of causes

1. Surface discoloration yellowing:

1.1 The formula is not stable enough, stabilizers and lubricants may not be properly matched, 

or the quality of the small ingredients in formula are not qualified;

1.2 Mixing temperature is too high or barrel, head temperature is too high;

2. Profile warping or bending:

2.1 Cooling is not uniform, or extrusion speed is too fast;

2.2 Shape mold, traction machine, head is not in a straight line

3. Scratches on the surface: 

There are unknown materials in the shaping die or the mouth die

4. Rough surface, poor gloss, cloudy phenomenon:

Poor plasticization, low temperature or extrusion is too fast or the quantity of Acrylic processing aids is small or with poor quality.

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

There is stagnant material at the merging core or in the mold.

6. Visible fusion lines or cracks in the profile:

Poor plasticization or too much external ubrications in the formula, cooling water entering into the cavity;

7. Profile is brittle:

Poor plasticization, too much lubrication or stabilizer too much, or not enough, lack of impact modifiers or with poor quality

8. Cost is too high and quality is poor:

The design of formula is not appropriate or the quality of small ingredients in the formula have quality problems.

You may encounter a variety of problems in the process of producing PVC Profiles, 

Most of the problems may be too much plasticizing or poor plasticizing, materials stuck in the machine or unknown material, 

or cooling uniformity or traction speed and other issues... 

Of course, other causes may also occur, so when encountering specific problems, 

it is also necessary to analyze specifically according to the actual situations.