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What are the common faults and troubleshooting methods of the bottle blowing machine

Fault 1: PET bottle transparency is not good
   Reasons: 1. The heating temperature is too high; 2. The heating time is too long; 3. The compressed air contains water; 4. The injection embryo tube itself is opaque; 5. The embryo tube design is not suitable; 6. The expansion ratio is too small.
Elimination methods: 1. Cool down; 2. Shorten heating time; 3. Use a dryer to remove water; 4. Improve embryo tube quality, select materials and increase raw material dryness; 5. Improve embryo tube size design; 6. Reduce embryo tube diameter.
  Fault 2: The PET bottle appears pearly and white
   Reasons: 1. The heating temperature is too low; 2. The thickness of the embryo tube is uneven; 3. The thickness of the embryo tube is too thick, and the heating and penetration are insufficient;
   Elimination methods: 1. Increase the temperature or slow down the revolution speed; 2. Improve the quality of the embryo tube; 3. Reduce the thickness of the embryo tube, or try to increase the outer cover of the heating device to increase the surface temperature of the embryo tube.
  Fault 3: PET bottle bottom nozzle position shift
Reasons: 1. The blowing machine started blowing too early; 2. The stretch rod did not go down to the end; 3. The stretch rod and the center line of the bottle axis were offset; 4. The embryo tube wall thickness was uneven or the injection density was uneven; 5. Uneven heating.
Remedy: 1. Delay the blowing time or increase the descending speed of the stretch rod; 2. Adjust the position of the magnetic pole switch; 3. Adjust the position of the stretch rod; 4. Improve the quality of the embryo tube; 5. Improve the heating conditions or check the embryo tube Is there a problem with rotation?
  Fault 4: PET bottle wall thickness is uneven
Reasons: 1. The position of the stretch rod is not in the center of the embryo tube; 2. The blow holes are asymmetrical and the hole diameter is different; 3. The stretching ratio is too low or the inflation ratio is too small; 4. The embryo tube does not rotate in the heating furnace; 5. , The embryo tube wall thickness is uneven or the injection density is uneven.
  Removal methods: 1. Adjust the position of the stretch rod; 2. Adjust the position and aperture of the blowing hole; 3. Increase the stretching ratio or inflation ratio; 4. Check the rotation device of the automatic bottle blowing machine; 5. Improve the quality of the embryo tube.
  Fault 5: The upper part of the bottle is too thick
   Reasons: 1. The temperature of the upper part 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.
  Removal method: 1. Heat the upper part; 2. Adjust the position of the vent hole; 3. Increase the stretching ratio; 4. Change the bottle shape; 5. Adjust the speed of the stretching rod.
   Fault 6: The bottom of the bottle is too thin
   Reasons: 1. The blowing machine starts blowing too early; 2. The bottom temperature is too high; 3. The bottom of the embryo tube is too thin.
  Removal methods: 1. Delay the start of blowing time; 2. Reduce the bottom temperature; 3. Increase the thickness of the bottom of the embryo tube.
   Fault 7: The bottle clamping line is obvious
   Reasons: 1. The clamping pressure is not enough; 2. The sealing time is too early; 3. The mold problem; 4. The size of the germ tube tooth mouth does not match the mold.
Remedy: 1. Increase the mold clamping pressure and adjust the angle of the mold clamping support rod; 2. Move the mold clamping stroke switch position back; 3. Repair the mold or check the mold assembly position, such as whether the guide post is loose or whether the mold is not Press tightly; 4. Repair the matching position of the mold teeth;
  Fault 8: The bottom of the bottle or the neck of the bottle is rolled up and material is accumulated
   Reasons: 1. Delayed blowing time is too long; 2. One roll, one good; 3. The temperature at the material accumulation is too low; 4. The air pressure for the action is unstable, which affects the descending speed of the stretching rod.
Remedy: 1. Shorten the delayed blowing time or reduce the descending speed of the stretching rod; 2. Reduce the air volume on one side of the coil; 3. Increase the heating temperature of the embryo tube; 4. Add an air storage tank to the air Source, or shorten the gas supply line.
  Fault 9: The bottom of the bottle is stretched and perforated
   Reasons: 1. Insufficient temperature and no penetration; 2. Delayed stretch time is too long; 3. Stretch ratio is too large; 4. The bottom of the embryo tube is too thin; 5. The stretched rod head is too sharp.
   Elimination methods: 1. Warm up; 2. Shorten the delay stretch time; 3. Reduce the stretch ratio; 4. Improve the design of the bottom of the embryo tube; 5. Trim and stretch the head.
   Fault 10: Blowing of the bottom of the bottle blowing machine
   Reasons: 1. Delayed blowing time is too short; 2. Delayed mold opening time is too short; 3. Temperature is too high; 4. Exhaust valve does not work.
  Removal methods: 1. Lengthen the delayed blowing time or increase the descending speed of the stretch rod; 2. Lengthen the delayed mold opening time; 3. Cool down; 4. Clean the exhaust valve with gasoline.
   Fault 11: The bottom of the bottle is not full
Reasons: 1. The bottom temperature of the bottle is too high; 2. The vent hole at the bottom of the mold is insufficient or uneven; 3. The stretch rod does not reach the bottom; 4. The design of the stretch rod head does not conform to the shape of the bottom of the embryo tube; 5. Blowing Insufficient air pressure; 6. Insufficient flow of blowing valve; 7. Poor design of bottom curve.
Remedy: 1. Lower 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 vent holes and make them evenly distributed; 3. Adjust the stretch rod to the bottom of the bottle; 4. Replace the stretch rod head; 5. Increase the blowing pressure; 6. Clean the blowing valve with gasoline; 7. Increase the streamline design of the bottom of the bottle.
  Fault 12:
Reasons: 1. If the tooth part of the embryo tube is in a specific position, it is the cause of the uneven thickness of the embryo tube; 2. If the mold clamping line is in a specific position relative to the mold clamping line, it is a mold exhaust problem; 3. The embryo tube Uneven heating; 4. Poor design of the bottom of the mold.
  Removal methods: 1. Improve the thickness design of the embryo tube; 2. Improve the vent at the bottom of the mold; 3. Improve the heating conditions; 4. Improve the bottom design.

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