2026-06-29
A double seam matrix prevents leakage only when four gates agree: the seam geometry is correct, the sealing compound is held under the right compression, visible defects are absent, and the production lot boundary is proven by measurement and leak evidence. "Zero leakage" is not achieved by one good seam number; it is achieved by a controlled relationship among body hook, cover hook, overlap, tightness, countersink, end fit, seamer setup, and line events.
