Many cap manufacturers struggle with unstable surface quality during cold dry winter months, an issue we've observed across years of onsite machine after-sales service. Unlike common machining burrs, tiny invisible scratches on aluminum cap threads rarely show up in normal-temperature production, yet become quite prevalent in dry winter workshop conditions.
Workshop air humidity dropping below 35% is the key trigger. In such dry environments, the micro oil film attached to aluminum materials evaporates faster during thread cold rolling processing. Insufficient surface lubrication leads to direct dry friction between the roller and aluminum blank, creating dense micro scratches on thread surfaces. These subtle flaws do not damage thread basic usability, but they lower surface finish consistency and may drag down the overall visual qualification rate by roughly 28% in winter batch production.
Most factories simply increase lubricant usage blindly, which easily causes oil residue and secondary contamination on finished caps. Based on our seasonal production tests for aluminum cap thread processing, we have summed up a targeted dry-season lubrication scheme instead.
We fine-tune two core parameters for winter operation: appropriately raising the uniform oil film thickness by a small margin and adjusting automatic spraying intervals according to real-time workshop humidity. This mild optimization maintains stable lubrication during high-speed cold rolling, relieves dry friction effectively, and greatly cuts thread micro-scratch occurrences.
This seasonal adjustment fits regular mass production well, requiring no major machine modification. It helps factories maintain steady finished cap surface quality throughout dry winter seasons.
