Bulging: Bulging (鼓包)
A local raised area or bump near a zipper, often where teeth, end stops or seam allowances pile up. It can come from injection shrinkage, thick stop moulds, bulky seam construction or uneven pressing. Bulging affects appearance and comfort and may cause the slider to catch. Solutions include thinner end parts, trimming seam allowances, better moulding control and pressing with suitable pads. Inspectors check both face and back of the finished seam.