In PET bottle manufacturing, even minor errors can lead to major production losses. Common PET bottle defects such as pearlescence, flash, and uneven wall thickness not only affect quality but also increase rejection rates. Effective stretch blow moulding troubleshooting starts with one critical factor—mould precision. At Awanti Polymoulds , we know that mould efficiency is the silent engine behind every successful production run. When your equipment is optimised, material saving in blow moulding becomes a natural outcome rather than a constant struggle. 7 Common PET Bottle Defects & The Mould Quality Connection Even the most advanced blow moulding machines can’t compensate for a mediocre mould. Here is how mould precision directly impacts the most common PET bottle defects . 1. Pearlescence (Over-stretching) This "whitish" appearance occurs when the PET material is stretched beyond its natural limit. While often a temperature issue, a poorly designed m...