1. Feeder
  • Glass too cold 

 
1. Feeder
  • Adjust gob temperature

 
2. Machine Setup and Operation
  • Blank contact time too long
  • Counterblow time too long
  • Excessive final blow pressure
  • Insufficient parison reheat time
  • Molds too hot
  • Excessive machine cooling
  • Blow head exhaust holes (equalizer) plugged

 
2. Machine Setup and Operation
  • Shorten blank contact time
  • Shorten counterblow time
  • Reduce final blow pressure
  • Increase reheat time
  • Adjust mold cooling

 
3. Mold Equipment
  • Molds not correctly vented
  • Rough mold seams

 
3. Mold Equipment
  • Correct the mold venting
  • Change molds and repair the seams