1 - Take a measuring calliper A
2 - Bearing in mind that the external wear on the bushing B is usually of three types, namely:
• UM – Forward drive wear
• UR – Radial wear
• URM – Reverse drive wear
3 - Bearing in mind that this check should be carried out before 250 hours (three-monthly), proceed with measurement
4 - Proceed with measurement of each of the three positions and consider the greatest of the three
5 - Use the table below to find the respective Øi (initial diameter) of the bushings B that corresponds to the code of your undercarriage, and note it down for use in subsequent measurements
6 - The acceptable wear limit corresponds to 75% of the initial value Øi: therefore, when the corresponding value is reached replace all the catenary bushings B; checks on other abrasion zones will still need to be carried out