DETECTION OF DELAMINATION OF RUBBER COVERS FROM METAL SUBSTRATES

摘要

The bonding of an elastomeric cover (22) to a metal roll (20) is tested by transmitting audible frequency waves through the compliant roll cover and receiving the waves at a transducer (38) mounted to the underlying steel rol l. The resulting signal may be analyzed by a technician listing to the audio frequencies transmitted. The audio range of frequencies employed may be abou t 5000 Hz. The elastomeric material such as rubber does not transmit sound without considerable loss of amplitude, whereas sound travels at high speed through steel with little attenuation. A sound transmitter (28) is spirally scanned along the rubber-covered surface of the roll, transmitting into the steel roll directly beneath the sound transmitter and throughout the roll. Sound is detected at a transducer (38) mounted at the roll ends. Any failure or significant variation in the roll/cover bond is detected by the effect on the quality of sound transmitted through the rubber steel interface.