This quality used testing machine is ideally installed directly in the production line of food cans. It has a simple operating principle for the elimination of defective cans (pin holes, dented flanges, cracked flanges, cracked welds, etc.). Standard vacuum degree is applied to cans and those found fault will be automatically rejected. Can height can be set with simple adjustments in about 5 minutes. Changeover of diameter is also possible by means of tool kits (setting in 50 minutes). The infeed belt with screw feeds cans to the rotary testing unit with 40 heads. As each head completes a full revolution, it depressurizes the can being tested to a standard pressure value. Any variations detected in this depressurization mean there is a leak in the can, so the machine produces an electronic signal or ejects the can. After testing, the good cans are reinserted in the production line.