Foreword

ISO (the International Organization for Standardization) is a worldwide federation of national standards bodies (ISO member bodies). The work of preparing International Standards is normally carried out through ISO technical committees. Each member body interested in a subject for which a technical committee has been established has the right to be represented on that committee. International organizations, governmental and non-governmental, in liaison with ISO, also take part in the work. ISO collaborates closely with the International Electrotechnical Commission (IEC) on all matters of electrotechnical standardization.

The procedures used to develop this document and those intended for its further maintenance are described in the ISO/IEC Directives, Part 1. In particular, the different approval criteria needed for the different types of ISO documents should be noted. This document was drafted in accordance with the editorial rules of the ISO/IEC Directives, Part 2 (see www.iso.org/directives).

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This document was prepared by Technical Committee ISO/TC 153, Valves, in collaboration with the European Committee for Standardization (CEN) Technical Committee CEN/TC 69, Industrial valves, in accordance with the Agreement on technical cooperation between ISO and CEN (Vienna Agreement).

This second edition cancels and replaces the first edition (ISO 28921‑1:2013), which has been technically revised.

The main changes are as follows:

— extension of the scope to include sizes DN 950 to 1 800, NPS 38 to 72, and pressure designations PN 400 and Class 2 500;
— addition of a new terminological entry for shell (3.14);
— addition of a new terminological entry for drip plate (3.15);
— exclusion of safety valves and control valves;
— in 5.2, addition of type test requirement in accordance with ISO 28921‑2;
— update of Annex A giving the test procedure for production testing of valves at low temperature.

A list of all parts in the ISO 28921 series can be found on the ISO website.

Any feedback or questions on this document should be directed to the user’s national standards body. A complete listing of these bodies can be found at www.iso.org/members.html.

BS EN ISO 28921-1:2022

Industrial valves. Isolating valves for low-temperature applications - Design, manufacturing and production testing

Current

Published:

31 Jul 2022