Auditing a warehouse cage manufacturer means going down to the workshop rather than staying in the office sample room. Focus on four stages — cutting, welding, surface treatment and final assembly inspection — because each one reveals the maker's true process level and quality-control capability.
On cutting, check the equipment: whether CNC cutters and straightening machines are in place, and whether the steel wire is cut cleanly to the ordered size. Look at the raw-material yard — sections should be stacked by specification, because mixing sizes leads to out-of-spec wire diameter. A good cutting area is tidy, clearly labeled and free of burrs on cut ends.
Welding is the core: check whether the welders are medium-frequency or ordinary spot welders and whether the welds are even. See whether mesh panels and the frame are spot-welded or fully welded, and whether key load-bearing points are fully welded. Check whether slag removal has its own dedicated step. Inside Nanjing Tongnuo's 9,000 m² workshop, the welding area is split into two lines — spot welding for mesh panels and full welding for the frame — and samples can be inspected on site.
For surface treatment, look at pre-treatment: whether there is pickling-phosphating or shot-blasting line, and whether the finish is galvanized or powder-coated. For hot-dip galvanizing, check zinc thickness and racking method; for powder coating, check pre-treatment and curing temperature. Finally, see the final inspection area: whether there are stacking tests, load tests and dimensional sampling stations.
Checklist: cutting equipment, welding process, slag removal, pre-treatment line, surface-treatment method, finished-product inspection stations, and live measurement of a sample cage. Walk the workshop before talking price; it tells you far more about the maker's real level than the quotation alone.