IEC 60471:2020 pdf free download

IEC 60471:2020 pdf free download Clevis and tongue couplings of string insulator units – Dimensions
This international standard applies to string insulator units of the cap and pin type and also ofthe long rod type as well as the fittings used with such insulators.
The object of this document is to define the dimensions of a series of clevis and tonguecouplings to permit the assembly of insulators or fittings supplied by different manufacturers.
NOTE 1 IEC 60305 gives the coordination between the standardized dimensions of Table 1 and the strengthclasses of cap and pin insulator. IEC 60433 gives the coordination between the standardized dimensions of Table 2and the strength classes of long rod insulators.
NOTE 2 lf the dimensions given in Table 1 are not sufficient, higher strength classes are given in lEC 60305.
2Normative references
The following documents are referred to in the text in such a way that some or all of theircontent constitutes requirements of this document. For dated references,only the editioncited applies.For undated references, the latest edition of the referenced document (includingany amendments) applies.
IEC 60050-471:2007,International Electrotechnical Vocabulary (IEV) – Part 471: Insulators
IEC 60120:2020,Ball and socket couplings of string insulator units – Dimensions
3Terms and definitions
For the purposes of this document, the following terms and definitions 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.org/obp
3.1
clevis and tongue coupling
female part of a clevis and tongue coupling with a U-shaped opening into which the tonguecoupling can be fitted
Note 1 to entry: A clevis contains two holes through which the coupling pin may pass to couple the twocomponents.
3.2
clevis
female part of a clevis and tongue coupling with a U-shaped opening into which the tonguecoupling can be fitted Note 1 to entry: A clevis contains two holes through which the coupling pin may pass to couple the twocomponents.
3.3
tongue
male part of a clevis and tongue coupling with a tongue-shaped extremity which fits into the U-shaped opening of the clevis and which contains a hole through which the coupling pin may be passed
3.4
coupling pin
rigid pin which passes through the holes in the clevis and tongue to couple them together
Note 1 to entry: On one end, the coupling pin has a stud head and on the other a security device (e.g. split pin) is placed to hold the pin in its place.
4 Couplings
4.1 General
Two coupling systems are recommended:
– Couplings with limited movement;
– Couplings with unlimited movement.
4.2 Couplings with limited movement
Couplings according to Figure 1 , and Table 1 , for which a limited movement of the tongue in the clevis needs to be assured.