TROUBLE SHOOTING PET BOTTLE BLOW MOULDING PROCESS
Problem : Haze
Possible Causes : IV too low, Preform too hot, Low level crystallinity in preform
Problem : Pearlescence
Possible Causes : Preform too cold, Insufficient soak time, Improper preform design
Problem : Pearlescence in a Particular Section
Possible Cause : Affected section too cool
Problem : Thin Sidewalls
Possible Causes : Preform too hot, IV too low, excessive preform moisture, improper heating profile
Problem : Heavy neck area
Possible Causes : Preform too hot, IV too low, excessive preform moisture, improper heating profile, too much heat in bottom area, pre-blow air starting too early
Problem : Shelf life failure
Possible Causes : Preform too hot, IV too low, Excessive preform moisture, Improper heating profile
Problem : Heavy bottom area
Possible Causes : Preform too hot, IV too low, Excessive preform moisture, Improper heating profile, Too much heat in top area, pre-blow air starting too late
Problem : Drop Test Failure
Possible Causes : Preform too hot, IV too low, Excessive preform moisture, Improper heating profile, Too much heat in top area, Preblow air starting too late, Excessive gate crystallinity in preform
Problem : Top Load Failure
Possible Causes : Preform too hot, IV too low, Excessive preform moisture, Improper heating profile, Too much heat in top area, Preblow air starting too late
Problem : Creep
Possible Causes : Preform too hot, IV too low, Excessive preform moisture.
Problem : Localized Surface Imperfections
Possible Causes : Water in blow air, Contamination, Small un-melts in preforms