Stacking load is the easiest item to get wrong in warehouse cage selection. Many people see a 1-ton per-cage load rating and dare to stack three layers, but the bottom cage actually carries the weight of the two cages above plus their goods. For a three-layer stack, the bottom must be sized as a multiple of a single fully loaded cage — not from a single layer alone.
Rule of thumb: stacking n layers means the bottom cage must carry n−1 layers at full load, with a safety factor of 1.2–1.5. With one cage fully loaded at 1 ton and a three-layer stack, the bottom cage should handle about 2.4–3 tons of equivalent load; beyond the cage's rated load, up-size wire, plate or add a bottom reinforcing beam.
Off-center load is more dangerous. When goods are unevenly distributed or the center of gravity shifts, one corner or one side of the bottom cage takes several times the average load; long-term off-center loading causes post or bottom weld cracks. So heavy bays go low, light ones high, and goods should sit as evenly as possible.
In selection, Nanjing Tongnuo (Xintongnuo) issues load-calculation recommendations based on actual stack layers and goods weight distribution. With a 9,000 m² factory and over 1,000 customers served, we can thicken the bottom, densify mesh panels or add reinforcing beams for high-stack scenarios, ensuring long-term use without deformation.
For high-stack cages already in service, periodically inspect the bottom cage's post-to-base joints, and reinforce or reduce layers when bulges or cracks appear. When buying new cages, write the stacking load into the technical agreement, and require a stacking compression test before dispatch.