This part of IEC 63182 specifies the dimensions that are of importance for mechanical interchangeability for a preferred range of U-cores made of metallic magnetic powder and gives guidelines on allowable limits of surface irregularities applicable to U-cores.
This document is a specification that is useful in the negotiations between magnetic powder core suppliers and users about surface irregularities.
The use of "derived" standards which give more detailed specifications of component parts while still permitting conformance with this document is discussed in Annex A.
IEC 63182-8:2025