ISO DIS 23467
Ice plug isolation of piping in nuclear power plant
|Publication Date:||30 January 2020|
|ICS Code (Nuclear power plants. Safety):||27.120.20|
This document specifies requirements for the ice plug technique with liquid nitrogen or dry ice as refrigerant (cryogenic medium) on metal pipes of nuclear power plants. The freezing liquid can be water or water mixture (e.g. boric acid mixture).
This document specifies technical requirements of ice plug generation, formation judgment and removal, measures before, during and after ice plugging and requirements for personnel and non-destructive testing.
This document is applicable for maintenance work, modification work and test inspections work when no other locking opportunity than ice plugging is available.
The application of the ice plug isolation technique is principally not allowed on cladded pipes or pipes with internal coatings. The application for pressure test is not in the scope of this document and should be qualified separate.