Infrared Inspection of Nonpneumatic Rubber Road Wheels
The examination of twelve used solid rubber road wheels by an infrared (IR) temperature profiling technique during drum test experiments is described. The IR method was evaluated as a noncontact means of predicting road wheel integrity by analysis of the circumferential temperature profile. The effectiveness of the temperature profiling method was determined by stripping the rubber from each wheel and visually evaluating the bond interface and rubber tread. Known defects in the used wheels were used to evaluate the IR examination method. Left and right sidewall and tread area were examined simultaneously by use of three sensor heads which were mounted in a test rig positioned around the test wheel. Results indicate that the IR test technique has a capability of detecting cracks and chunking in the rubber tread, gross unbonded areas and interface delamination, and large‐area entrapped foreign objects at the rubber‐to‐metal interface. Low bond strength and small unbonded areas less than one square inch were not detected. Defects located along the left sidewall area were more difficult to sense because of the wear flange and high thermal coupling with the metal sidewall, which dissipated tread‐developed heat.Abstract