Regulatory oversight of nuclear safety in Finland. Annual ... - STUK

4.1 Loviisa NPP
Spare parts management at
the Loviisa power plant
In 2011, STUK inspected the sufficiency of spare
parts for systems and equipment important to
safety and the functionality of spare parts management
at the Loviisa power plant. The inspection focussed
in particular on the spare parts inventory of
systems and equipment important to safety as well
as on the procedures used at the power plant for
monitoring the spare parts needs and for procuring
spare parts. The inspection found that the licensee
is aware of the challenges related to the availability
of spare parts and initiated in 2011 an investigation
regarding spare parts requirements. STUK
deems the investigation and its completion important.
Furthermore, STUK found that the overall
responsibilities, procedures and instructions regarding
spare parts management must be further
specified so that the spare parts requirements of
systems and equipment important to safety are
foreseen and that the procurement procedures ensure
the timely availability of spare parts. Matters
requiring immediate corrective actions were also
observed in the storage conditions of spare parts
for systems and equipment important to safety,
such as further specification of procedures related
to the ageing and maintenance of the stored spare
parts as well as verification of the usefulness of
aged items in the store or their removal from the
store. The licensee must submit to STUK an account
of the immediate corrective actions by the
beginning of March 2012 and draw up, during the
spring 2012, a development plan for spare parts
management for the period 2012–2016. STUK considers
a long-term development plan necessary in
order to ensure the availability of spare parts for
the systems and equipment important to safety
throughout the entire planned service life of the
plant unit.
Spare part problems regarding
the pump motors of the highpressure
safety injection system
The spare part problems regarding the pump motors
of the high-pressure safety injection system
surfaced in 2010 when a spare motor was installed
in place of a faulty motor. The replacement motor
installed in the component location was the last
spare motor in store for the safety injection system
at the Loviisa power plant. Consequently, the pow-
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er plant has initiated the process for procuring new
motors. STUK has required the power company to
submit a plan and time schedule for replacing the
motors because the faults occurring in the pump
motors of the high-pressure safety injection system
indicate that the original Soviet-made motors
should be replaced.
Management of EDG spare parts
In conjunction with its inspections and regulatory
activities, STUK has paid attention to the
poor spare parts situation of the emergency diesel
generators at the Loviisa power plant and to the
procurement and availability of critical parts. The
goal must be to secure the long-term availability
of good quality spare parts for the EDGs. In order
to improve the situation, Fortum has concluded
a framework agreement with the motor supplier
for the spare parts required for basic maintenance
and for other separately specified critical mechanical
spares. The power company has also ordered
more spare parts with long delivery times to be
kept in store for the annual maintenance outages.
Furthermore, Fortum intends to audit the spare
parts suppliers among the motor supplier’s subcontractors
with whom quality problems have been
encountered. STUK will assess the sufficiency of
these actions in early 2012.
4.1.5 Development of the plant and its safety
In 2007, STUK issued its statement to the Ministry
of Trade and Industry (currently the Ministry of
Economy and the Employment) regarding the renewal
of Loviisa NPP’s operating licence and the
plant’s periodic safety review. Fortum Power and
Heat Oy presented, in connection with the periodic
safety assessment, an action plan for developing
the plant’s safety. It includes decreasing the risk of
accidents and releases through various actions and
supplementing the Probabilistic Risk Assessment.
The actions have, in the main, progressed in line
with the action plan. However, the intention is
to implement certain actions aimed at improving
safety in connection with the I&C upgrade of the
Loviisa power plant. The intention is to reduce the
risk associated with lifting heavy loads by modifications
implemented in connection with modernising
the fuel transfer machine. They will allow using
lifting routes more beneficial to plant safety.
Since the above projects have been delayed from
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