ISO 21012:2018 極低温容器—ホース | ページ 2

Foreword

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This document was prepared by ISO/TC 220, Cryogenic vessels.

This second edition cancels and replaces the first edition (ISO 21012:2006), which has been technically revised.

This edition includes the following significant changes with respect to the previous edition:

• Subclause 4.2: Added “any austenitic stainless steel hoses shall be annealed after formation for hydrogen service.”;
• Subclause 4.4.3: Replaced shall with should;
• Subclause 4.4.3: Replaced 50 000 cycles with 10 000 cycles;
• Subclause 4.4.3: Added “This test is only required if the flexible hose is subject to multiple wide/significant moves when under pressure.”;
• Subclause 5.3.2.1: Replaced 50 000 cycles with 10 000 cycles;
• Subclause 5.3.2.2: Replaced 50 000 cycles with 10 000 cycles;
• Annex B: Changed from Normative to Informative;
• Annex C: Changed from Normative to Informative;
• Annex C: Changed last sentence in second last paragraph to “Sufficient liquid nitrogen shall be used to ensure the flexible hose assembly reaches liquid nitrogen temperature.”.

1 Scope

This document specifies design, construction, type and production testing, and marking requirements for non-insulated cryogenic flexible hoses used for the transfer of cryogenic fluids within the following range of operating conditions:

• working temperature: from −270 °C to +65 °C;
• nominal size (DN): from 10 to 100.

End fittings for mounting of any couplings are within the scope of this document, but the couplings are subject to other standards.

It is intended that the hose be designed and tested to satisfy the generally accepted rated pressure i.e. at least PR 40. Hoses may be then selected with a PR equal to or greater than the maximum allowable pressure (PS) of the equipment to which it is to be used.

2 Normative references

The following documents are referred to in the text in such a way that some or all of their content constitutes requirements of this document. For dated references, only the edition cited applies. For undated references, the latest edition of the referenced document (including any amendments) applies.

3 Terms and definitions

For the purposes of this document, the terms and definitions given in ISO 7369 and the following apply.

ISO and IEC maintain terminological databases for use in standardization at the following addresses: