Current limits of PTFE in sliding bearings

摘要

The European standard EN 1337 on bridge bearings is supported by experimental studies dating tornthe ‘70s and the ‘80s, which are not suitable to account for recent issues relevant to operations ofrnsteel–PTFE bridge bearings under extreme conditions, like high environment temperatures or highrnvelocities of sliding. The investigations reported in the paper show that the strength of PTFE at highrntemperatures is underestimated by the standard, leading to unnecessary need for over sizing thernbearings. On the other hand, increase in wear rate and reduced service life shall be carefullyrnconsidered for PTFE bearings operating at high velocities. Under severe conditions in terms of highrnspeeds and increase in temperature at the sliding interface the actual wear life of PTFE can berndramatically reduced with respect to the figure given in the standard.