May 10, 2023
Poor transparency of PET bottles
Reason:
1. Heating temperature is too high;
2. Heating time is too long;
3. Compressed air contains moisture;
4. The injection molded embryo tube itself is not transparent;
5. Inadequate embryo tube design; 6. The blowing ratio is too small.
Troubleshooting:
1. Cooling down;
2. Shorten heating time;
3. Use a dryer to remove water;
4. Improve the quality of embryo tubes, select materials and increase the dryness of raw materials;
5. Improve the design of embryo tube size; 6. Reduce the diameter of the embryo tube.
Pearly luster and whitening appear on PET bottles
Reason:
1. Heating temperature is too low;
2. Uneven wall thickness of embryonic tubes;
3. The thickness of the embryo tube is too thick, and the heating penetration is insufficient.
Troubleshooting:
1. Raise the temperature or slow down the revolution speed;
2. Improve the quality of embryo tubes;
3. Reduce the thickness of the embryo tube, or try raising the outer cover of the heating device to increase the surface temperature emission of the embryo tube.
PET bottle bottom nozzle position offset
Reason:
1. Start blowing too early;
2. The stretching rod did not reach the bottom;
3. The stretching rod is offset from the centerline of the bottle shaft;
4. Uneven wall thickness or injection density of embryonic tubes; 5. Uneven heating.
Troubleshooting:
1. Delay the blowing time or increase the lowering speed of the stretching rod;
2. Adjust the position of the magnetic pole switch;
3. Adjust the position of the stretching rod;
4. Improve the quality of embryo tubes;
5. Improve heating conditions or check for any issues with embryo tube rotation.
Uneven wall thickness of PET bottles
Reason:
1. The position of the stretching rod is not in the center of the embryo tube;
2. Asymmetric blowing holes with varying pore sizes;
3. The stretching ratio is too low or the blowing ratio is too small;
4. The embryo tube does not rotate in the heating furnace;
5. Uneven wall thickness or injection density of embryonic tubes.
Troubleshooting:
1. Adjust the position of the stretching rod;
2. Adjust the position and aperture of the blowing hole;
3. Increase the stretching ratio or blowing ratio;
4. Check the rotation device; 5. Improve the quality of embryo tubes.
The upper part of the bottle is too thick
Reason:
1. The upper temperature is too low;
2. The position of the mold exhaust hole is too far from the upper part;
3. The stretching ratio is too low;
4. The inflation ratio of the upper part of the bottle is too low;
5. The stretching rod speed is too slow.
Troubleshooting:
1. Upper heating;
2. Adjust the position of the exhaust hole;
3. Increase the stretching ratio;
4. Change the shape of the bottle;
5. Adjust the stretching rod speed
The bottom of the bottle is too thin
Reason:
1. Start blowing too early;
2. The bottom temperature is too high;
3. The bottom of the embryo tube is too thin.
Elimination method:
1. Delay the start of blowing time;
2. Lower the bottom temperature;
3. Increase the thickness of the embryo tube bottom.
Obvious bottle molding line
Reason:
1. Insufficient clamping pressure;
2. The sealing time is too early;
3. Mold issues;
4. The size of the embryo tube mouth does not match the mold.
Troubleshooting:
1. Increase the clamping pressure and adjust the angle of the clamping support rod (<5 degrees);
2. Move the position of the closing stroke switch backward;
3. Repair the mold or check the assembly position of the mold, such as whether the guide pillar is loose or whether the mold is not tightly pressed;
4. Repair the fitting position of the mold teeth.
Roll up or accumulate material at the bottom or bottleneck of the bottle
Reason:
1. The delayed blowing time is too long;
2. One roll, one good;
3. The temperature at the accumulation site is too low;
4. The air pressure used for the action is unstable, which affects the lowering speed of the stretching rod.
Troubleshooting:
1. Shorten the delayed blowing time or reduce the lowering speed of the stretching rod;
2. Reduce the air volume on one side of the roll bottle;
3. Increase the heating temperature at this location of the embryo tube;
4. Install an air storage tank to activate the air source or shorten the air supply pipeline.
Bottle bottom stretching perforation
Reason:
1. Insufficient temperature and lack of penetration;
2. Delayed stretching time is too long;
3. The stretching ratio is too large;
4. The bottom of the embryo tube is too thin;
5. The stretching rod head is too pointed.
Troubleshooting method:
1. Heating;
2. Shorten the delayed stretching time;
3. Reduce the stretching ratio;
4. Improve the design of the embryo tube bottom;
5. Round the stretching rod head.
Bottle bottom blasting
Reason:
1. The delayed blowing time is too short;
2. The delayed mold opening time is too short;
3. The temperature is too high;
4. The exhaust valve is not working.
Troubleshooting:
1. Extend the delayed blowing time or increase the lowering speed of the stretching rod;
2. Extend the delayed mold opening time;
3. Cooling down;
4. Clean the exhaust valve with gasoline.
Bottle bottom not full
Reason:
1. The temperature at the bottom of the bottle is too high;
2. Insufficient or uneven exhaust holes at the bottom of the mold bottle;
3. The stretching rod has not reached the bottom;
4. The design of the stretching rod head does not conform to the bottom shape of the embryo tube;
5. Insufficient blowing pressure;
6. Insufficient flow rate of the blowing valve;
7. Poor design of bottle bottom curve.
Troubleshooting:
1. Reduce the temperature at the bottom of the heating zone or use a damp cloth to lower the temperature at the bottom of the embryo tube;
2. Increase the number of exhaust holes and distribute them evenly;
3. Adjust the stretching rod to the bottom of the bottle;
4. Replace the stretching rod head;
5. Increase the blowing pressure;
6. Clean the blowing valve with gasoline;
7. Add streamline design of bottle bottom curve.
PET bottle bottom nozzle position offset
Reason:
1. Start blowing too early;
2. The stretching rod did not reach the bottom;
3. The stretching rod is offset from the centerline of the bottle shaft;
4. Uneven wall thickness or injection density of embryonic tubes;
5. Uneven heating.
Troubleshooting:
1. Delay the blowing time or increase the lowering speed of the stretching rod;
2. Adjust the position of the magnetic pole switch;
3. Adjust the position of the stretching rod;
4. Improve the quality of embryo tubes;
5. Improve heating conditions or check for any issues with embryo tube rotation.
