INTERNATIONAL COMPARISON OF HIGH-ACCURACY ROUNDNESS MEASUREMENTS

An international comparison of roundness measurements at the highest l evel of accuracy has been carried out between eight European laborator ies. Three roundness standards with different designs and roundness de viations were measured. One standard was a commercially available type , two standards were developed for the purpose of this comparison. The agreement between the laboratories was within +/-20 nm for the standa rd with the smallest roundness deviation. The comparison was sponsored by the Commission of the European Communities.