Checking thermoplastic crates for ageing - subjecting part to standardised mechanical or physical test which reveals excessive ageing

摘要

In the parent patent plastic containers, partic. polythene or similar bottle crates, are tested/checked as to their suitability for further use. In this addn. the containers are physically or mechanically tested e.g. in a prodn. line, continuously or intermittently, by measuring their extension, yield, modulus of elasticity, bending load or deflection, structure (ultrasonically), electrical conductivity, or freedom from surface cracks, testing at at least one part such as the edge of the handle/grip area. Test selected reveals whether article has aged too far for continued use; simple reliable automatic operation, has no effect upon life of articles tested. Specification printed 25.2.82.