Craze

◆ possible causes related to process and equipment

1. The barrel temperature is too high
2. The screw speed is too fast
3. The nozzle is too small, too hot, or blocked
4. The glue injection volume exceeds 80% of the machine capacity
5. There is gas or water vapor in the melt
6. Incomplete cleaning

◆ possible causes related to the mold

1. The gate is too small
2. Gate or runner blockage
3. There are micro cracks on the mold surface

◆ possible causes related to materials

1. The material is not sufficiently dry
2. Materials contain foreign matters
3. High-temperature decomposition of materials

Surface peeling

◆ possible causes related to process and equipment

1. The barrel temperature is too low
2. The injection speed is too slow.
3. Insufficient holding pressure (time)

◆ possible causes related to the mold

1. Mold temperature is too low
2. Gate or runner severely bent
3. Improper gate type selection
4. Too much release agent

◆ possible causes related to materials

1. Poor drying of materials
2. Too much material returned
3. Incompatible additives

Black stripe

◆ possible causes related to process and equipment

1. The firing speed is too fast
2. The melt temperature is too high
3. The injection pressure is too high
4. The diameter of the nozzle is too small
5. Nozzle temperature is too high
6. High material pipe temperature
7. The molding cycle is too long
8. There are carbides in the material pipe

◆ possible causes related to the mold

1. Improper gate type or position
2. Gate diameter is too small

◆ possible causes related to materials

1. The high-temperature stability of the material is not enough
2. Materials contain foreign matters

Chromatic aberration

◆ raw material problems

1. The selected colorants or other additives have poor thermal stability
2. The selected colorant reacts and decomposes with resin or added additives
3. The rheological property of raw materials is too low

◆ processing technology problems

1. The drying time is too long or the drying temperature is too high
2. The injection temperature or pressure is too high
3. The retention time is too long, resulting in discoloration
4. The injection molding machine is not clean and polluted

◆ surrounding environment and other influencing factors

1. Raw materials or products should not be stored in direct sunlight
2. The difference in the type of color difference meter or its insufficient color measurement accuracy
3. Influence of product temperature during color difference measurement

Insufficient filling

◆ possible causes related to process and equipment

1. Insufficient glue melt
2. The barrel temperature is too low
3. Poor back pressure setting
4. Insufficient injection pressure (speed)
5. Injection molding time is too short
6. Large clearance of check valve
7. Nozzle blockage

◆ possible causes related to the mold

1. Mold temperature is too low
2. Improper choice of gate type or position
3. Poor mold exhaust
4. The runner (gate) of the mold is too small
5. Uneven distribution of mold cavity

◆ possible causes related to materials

1. Poor liquidity of materials
2. Poor drying of materials

Warping

◆ possible causes related to process and equipment

1. Improper injection pressure or time
2. The melting time in the feeding tube is too long
3. Improper forming cycle
4. The barrel temperature is too low
5. Low nozzle temperature
6. Improper holding pressure and time

◆ possible causes related to the mold

1. Mold temperature is too high or too low
2. The gate or runner is too small
3. Improper gate type or position
4. Uneven mold temperature
5. The area of the ejector rod is too small or the distribution is unbalanced
6. The wall thickness deviation is too large

◆ possible causes related to materials

1. Improper liquidity
2. Large deviation of longitudinal and transverse shrinkage of materials