Hidden Quality Risk of Inconsistent Cap Bottom Flatness After Thread Processing

Many cap manufacturers overlook a subtle but impactful processing flaw in aluminum thread cap and tamper-proof cap production: bottom flatness deformation after thread rolling.

In conventional thread processing equipment, unbalanced one-way rolling stress transfers evenly across the cap body. This creates tiny, invisible bottom warping of 0.02–0.05mm on finished caps, too minor to catch in regular manual inspections. While the defect barely affects semi-manual production, it triggers obvious problems for modern high-speed filling lines.

Our long-term market observation shows caps with slight bottom unevenness can cause 8–12% positioning offset during automatic high-speed filling and capping. This small deviation slows down line operation efficiency and occasionally leads to product jams or inaccurate assembly, troubling end users' continuous mass production.

As a professional packaging equipment manufacturer, we've optimized the core rolling structure based on years of on-site debugging experience. Our upgraded stress-balanced rolling design disperses concentrated one-way mechanical stress during thread forming.

This structural improvement helps retain the original flatness of cap bottoms without compromising thread precision. It works well to adapt to most mainstream fully automatic filling and capping integrated lines, helping factories reduce invisible production stability risks in downstream processes.