Serial Number

Abnormality

Reason

Solution

1

The profile bent or warped

The mold, tractor and the head are not in a straight line

Adjust the position of the mold and tractor

Uneven discharge of the machine head, resulting in internal stress

Adjust cooling water or cooling water distribution

Die temperature is uneven, resulting in internal stress

Adjust the temperature

The extrusion speed is too fast, and the profile cooling is poor

Reduced extrusion rate

2

Uneven profile surface

Traction speed is too fast, the profile can not stick to the wall in the mold

Reduce traction speed

Vacuum setting die vacuum degree is small

Check whether there is air leakage or the vacuum pump system is blocked

The mold position is high or low

Adjust the upper and lower positions of the mold

Poor cooling

Enhanced cooling effect

3

The surface of the profile is scratched

There's a foreign body in the mold

Cleaning head

There is scale on the surface of the mold or foreign body in the vacuum tank

Cleaning mold

4

There are bubbles in the section of the profile

The processing temperature is too high, and the material decomposes to produce gas

Reduce working temperature

Barrel cooling device failed

Check whether the barrel cooling device plays a cooling role when it exceeds the set temperature, and whether the cooling device fails.

There are too many volatiles in the raw materials

formula adjustment

The cylinder vacuum system is out of order

Check whether the vacuum system works normally and whether the pipeline is blocked

A new ingredient in the formula is not up to standard

Replacement of defective material

Low mixing temperature, moisture and volatile content can not be discharged

Increase the mixing temperature

5

The surface of the profile is rough, the luster is poor, and there is a cloud-like phenomenon

The inner wall of the die is not smooth and occupies precipitates

Cleaning die

Uneven material mixing

Check mixer impeller, mixing time is normal, take corresponding measures

The vacuum degree of molding die is not enough, and the profile sticking die is n

Increase vacuum

Too low temperature, poor plasticization

Raising temperature or increasing ACR processing AIDS, bright processing ACR is more effective

Extrusion speed is too fast, plasticizing is bad

reduction of speed

6

Decomposition occurs in the die and yellow lines appear on the surface of the profile

1Die head runner local polishing is not good, there is stagnant material

Polish the rough parts of the mold

2There are dead corners in the mold

mold repair

7

The profiles have obvious weld connections

Too low temperature, poor plasticization

Increase the temperature or increase the number of processing AIDS

The extrusion speed is fast, and the material is not plasticized

Reduce screw speed

Decomposition of raw material at welding site

Cleaning head

Unqualified formula (excessive slip agent or poor slip, precipitation, etc.)

Regulating formula

Mold design or structure is poor

Increase the length of the head shaping section

8

Profile size is unstable

Large temperature fluctuation

equilibrum temperature

The extrusion speed or traction speed is not stable

Stable extrusion speed or traction speed

Uneven material mixing (high mixer impeller wear or process conditions change)

Take measures according to specific reasons to ensure that the material is mixed evenly

Cooling efficiency is not high after improper size of cooling mold

Repair the mold or adjust the cooling process

Too much lubricant in the formula, back pressure

Adjust the formula to reduce the amount of lubrication

Mold vacuum is low, profiles can not stick to the wall

Regulating vacuum

The resistance at the qualitative die is unbalanced, resulting in internal stress

Adjust the discharge amount of the die, so that the extrusion speed of each part is as consistent as possible

Uneven cooling

Adjust cooling water or improve mold cooling system

The feed is unstable, which may be caused by material bridge, feeding screw screw and other reasons

Find out the cause of unstable material supply and take corresponding measures

9

High shrinkage of profiles

Poor cooling

Enhanced cooling effect

Excessive traction speed

Reduce traction speed

The head temperature is too high

Reduce the nose temperature

The components with high shrinkage rate in the formulation are too high

CPE Replace the part of the formula with a large shrinkage rate and replace it with an additive with less fraction or a lower shrinkage rate, such as ACR instead of CPE

10

Deformation of reinforced bar

Poor cooling effect

Enhanced cooling effect

Traction speed is too fast or too slow

Adjust the traction speed

Improper distance between mold and head

Adjust the distance between them

Traction machine track clamping force is too large

Adjust the clamping force

Vacuum degree is too small or vacuum fluctuation

Adjust or stabilize the vacuum pressure of the mold

11

Reduced strength of profiles (impact strength, bending modulus of elasticity)

Poor plasticization (low temperature or insufficient processing AIDS, high filling component in the formula)

Increase the temperature, or increase the amount of processing AIDS, reduce the amount of calcium powder

Improper formulation

Regulating formula

Uneven material mixing or poor preplasticization

Improve high mixer performance or process

Extrusion temperature is too high (causing over-plasticization or material decomposition)

Reduce the temperature

Low melt pressure

Adjust the formula (such as adding large molecular weight processing AIDS and impact resistance to help increase melt pressure), improve the mold, and reduce the mold temperature

Improper selection of impact resistance (for example, when adding CPE fraction for a long time, the elastic modulus will decrease significantly, and when adding a small amount, the impact strength will decrease)

Improving impact modifiers, such as using impact ACR, with less ACR addition fraction than CPE, can achieve the same impact effect, but has less impact on the elastic modulus

The traction speed is too fast, resulting in molecular chain tendency

Reduce traction speed

Cooling too fast

Shape to slow cooling, can not quench, quench causes the internal stress of the profile, reduce the strength

Poor weldability

Excessive lubricant or melting point is too low, easy to precipitate, so that the welding strength is reduced, adjust the lubricant content or replace the lubricant

There are components in the formulation that greatly affect the strength of the weld

Regulating formula

Poor welding

Welding heating time, heating temperature, butt pressure and other technological conditions have an impact on the weld strength, experiment, adjust to the appropriate welding technological conditions

12

During the welding Angle strength test, the profile breaks outside the weld

The section and structure of the profile are unreasonable

Improve the mold

Insufficient strength of profile

According to 11, find the reasons for the influence strength

13

Profile surface discoloration

The formula design is not reasonable

1.Adjust the formula, adopt scientific and advanced formula system and non-toxic and efficient heat stabilization system to improve the comprehensive stability of heat resistance, light and oxygen;

2.Establish a laboratory for raw materials to improve the ability to analyze and judge the causes of surface discoloration of profiles;

3.Establish reliable and stable raw material supply channels to ensure the quality of raw materials;

4.Appropriately increase the amount of heat stabilizer, light stabilizer and antioxidant, and timely deal with the discoloration of the profile surface caused by changes in raw materials;

5.Packaging, storage and transportation of PVC-U profiles should be strictly in accordance with the requirements of GB8814.

Ingredients and raw material issues

CPE quality

Quality and dosage of heat stabilizer

Titanium dioxide quality