IEC 60401-1-2020 pdf free download – Terms and nomenclature for cores made of magnetically soft ferrites – Part 1: Terms used for physical irregularities and reference of dimensions.
This part of lEC 60401 provides a nomenclature of the most frequent surface, bulk and shape
irregularities relevant to cores made of soft ferrites (magnetic oxides). Most irregularities aregraphically exemplified as visual aids. A general recommendation is also given in Annex A for
a consistent scheme for specifying the exact location of the irregularity，combining a generalname for the location with more detailed qualifiers of the specified location. This documentcan also be useful as a terminology reference when preparing technical documentation,irregularity inspection specifications, etc.
This document also presents a method for defining the designation nomenclature for themajor physical attributes of soft ferrite core shapes. The purpose of this document is tofacilitate uniform usage of dimensional characters by manufacturers，specifiers,and userswhen describing core dimensions on drawings,in tables,and on catalogue specificationsheets.
2Normative references
There are no normative references in this document.
3 Terms and definitions
For the purposes of this document, the terms and definitions given in 4.2,4.3，4.5 andAnnex A apply.
IsO and lEC maintain terminological databases for use in standardization at the followingaddresses:
IEC Electropedia: available at http://www.electropedia.orgl
Iso Online browsing platform: available at http://www.iso.orgl/obp
4Physical irregularities
4.1General overview
Physical irregularities mean here the surface irregularities， bulk irregularities and shapeirregularities.The irregularity here stands for inconsistency of the state or quality of the part’s
surface, bulk or shape with its intended regularity.These irregularities are considered here in the macroscopic scale,i.e. within the range of linear dimensions of irregularities from onemicrometre to tens of millimetres.
There is a great variety of surface, bulk and shape irregularities degrading the quality of parts made of ferrites. Different types of these irregularities can often occur together and overlapone another.
Each type of irregularity is，in general，produced by one or more of the following: processvariability in a manufacturing step, handling, grinding, packing or transportation.
The extent of the quality degradation is dependent on the type, scale,and combination ofirregularities being present as well as on their locations on the part.There are locationsparticularly sensitive to the degrading effect of the specific types of irregularities.
The irregularities can in extreme cases have a detrimental or critical effect on magnetic,electric and mechanical performances of the part. Operations performed on the part, such asmarking,winding,assemblingand mounting,can also be adversely affected by theirregularities.
An ongoing tendency to upgrade the overall quality of the parts results in more stringentrestrictions being imposed on the quantity of irregularities in these parts.
This brings about a need for a set of definitions，or nomenclature，which would be a primarybasis for approaches to irregularities and their location issues.
Therefore, this nomenclature is intended to be used as a uniform reference when formulating
more detailed descriptions ofirregularities at specified locations，requirements andprocedures related to the inspection and assessment of irregularities. This nomenclature canalso be useful with regard to methods and tools used for detection，recognition andclassification of irregularities.
4.2General terms for physical irregularities
4.2.1
surface irregularity
unintentional state or appearance of the surfaces, edges and corners of the part
Note 1 to entry.: Some surface irregularities，if excessive,can so deform contours and surfaces of the part, thatthey may also be classified as shape irregularities.
4.2.2
interior irregularity
unintentional inhomogeneity inside the part
4.2.3
shape irregularity
unintentional deformation of the contour lines or surfaces delimiting the shape of the part
Note 1 to entry: In some cases，shape iregularities smaller than quoted tolerances can still disqualify the part.
4.2.4
tolerance
<dimensional>allowable difference between the nominal and permissible limit dimensions ofthe contour lines defining the part’s shape
4.2.5
location
<of the irregularity> position on or within the part where the irregularity is present.IEC 60401-1 pdf download.