1. Feeder
  • Glass too cold

 
1. Feeder
  • Adjust the glass temperature

 
2. Machine Setup and Operation
  • Too much settle blow, pressure and/or time of application
  • Plunger is too cold
  • Plunger contact time is not correct. If contact time is too long, the interior of the finish is cooled. If it is to short, the plunger may run cold, thus causing checks
  • Internal cooling nozzle loose or bent or not properly set, causing it to rub the inside of finish (by contact)
  • Drops of oil on the plunger

 
2. Machine Setup and Operation
  • Reduce settle blow pressure
  • Adjust the plunger cooling
  • Adjust plunger contact time
  • Check internal cooling nozzle-correctly fitted and straight
  • Fit drip to deflector

 
3. Mold Equipment
  • Plunger dirty, sticking in thimble guide ring
  • Incorrect plunger design
  • Incorrect plunger and cooling tube design (press and blow)

 
3. Mold Equipment
  • Change plunger and thimble
  • Adjust plunger design
  • Adjust plunger and cooling tube design

 

Note: It may cause leakage and thus spoil the product.