Assessment of the technical state, residual life and service life extension of fire-retardant coatings for NPP turbine hall metal structures

Introduction. The article examines methods and means of monitoring the fire-retardant coatings of metal structures used in turbine halls of operating NPPs during the works on the assessment of the technical state, residual service life and service life extension of fire-retardant coatings. This appears to be an extremely urgent task, especially within the framework of the NPP pre-operation and service life extension. For operating NPPs, the re-surfacing of fire-retardant coatings due to the service life expiration can represent an insurmountable task.

Aim. To establish current requirements for the content and sequence of works on the assessment of the technical state, residual life and service life extension of fire-retardant coatings applied to NPP turbine hall metal structures.

Materials and methods. An analysis of existing methods and techniques for assessing the technical state, residual service life and service life extension of fire-retardant coatings applied to the turbine hall metal structures of operating NPPs was carried out.

Results. The acknowledged methods and techniques for assessing the technical state, residual service life and service life extension of fire-retardant coatings are examined, their effectiveness is analyzed and promising trends on the establishment/forecast of the guaranteed service life are noted, including the development of promising fire-retardant compositions with an increased service life and the development of necessary programs-procedures for the establishment and substantiation of the guaranteed storage life of fire-retardant coatings, as well as the assessment of its extension.

Conclusion. The requirements for the content and sequence of works on the assessment of the technical state, residual life and service life extension of fire-retardant coatings applied to NPP turbine hall metal structures are established.

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