Approval of NP-104-18

On November 14, 2018 federal rules and regulations in the field of atomic energy use “Welding and overlay welding of equipment and pipelines of nuclear installations” (NP-104-18) were approved.

The rules establish the requirements for fabrication, assembling and maintenance of equipment and pipelines of nuclear installations concerning:

1. Welding and overlay welding, welding materials and equipment, preparation and assembling for welding, types of welded joints, heat treating of welded joints and deposited pieces;
2. Control of welding and surfacing material;
3. Defects fixing and its control.

Requirements for welding and overlay welding, welding materials and equipment, preparation and assembling for welding, types of welded joints, heat treating of welded joints and deposited pieces shall be taken into consideration in the development process of design (project) documentation.

Rules cover the processes of welding and overlay welding of the pieces and assembly units of:

a. Equipment and pipelines which are regulated by the federal rules and regulations in the field of atomic energy use “Rules of arrangement and safe operation of equipment and pipelines for nuclear facilities” (NP-089-15) approved by the Order №521 of the Federal Environmental, Industrial and Nuclear Supervision Service on December 16, 2015 and registered by the Ministry of Justice as №41010 on February 9, 2015.

b. Equipment and pipelines working under overpressure or vacuum pressure and related to the safety class 3 which are not subject to NP-089-15.

c. Support columns and suspension systems for equipment and pipelines indicated in subparagraphs “a” and “b” of this paragraph;

d. In-vessel internals of VVER reactors and fast neutron reactors;

e. Metal structures of spent fuel pools, refueling ponds and spent fuel storage pools of nuclear facilities.

Federal rules and regulations in the field of atomic energy use “Welding and overlay welding of equipment and pipelines of nuclear installations” (NP-104-18) were approved by the Order №554 of the Federal Environmental, Industrial and Nuclear Supervision Service on November 14, 2018.