SOME DOUBTS ABOUT ACCURACY TESTS OF MACHINE TOOLS ACCORDING TO ISO 230-2

摘要

There is a need for discussion on theoretical correctness and practical usefulness of tests on the machine too! accuracy performed without machining. Such tests are standardised by ISO 230-2. First edition of the standard was in 1988, the second one in 1997 and now ISO 230-2 is under revision. Even after 15 years of the international use there are some doubts concerning the thermal conditions described and required in the standard. Formulation of the environment temperature influence and the method of compensation thermal expansions of machine tool elements seem to be both unclear and doubtful. The compensation should be carried out when the environment temperature is not 20℃, but because of such instruction a very small difference of temperature may cause quite big difference in accuracy evaluation. Also the compensation procedure itself seems doubtful.