R1.06/05A - PIP Beloyarsk NPP - Replacement of safety related steam / water valves (Lot 1)

Beloyarsk NPP is situated in Sverdlovsk region of Russia, in the town of Zarechny, approximately 60 km east of Ekaterinburg and close to the Ural mountain range. It is one of the oldest commercial nuclear power plants in Russia and started operations in 1964. The first 2 units constructed at the site were AMB100 and AMB200 prototype units, which were forerunners of the RBMK reactors. These 2 units were shut down in 1981 and 1989 respectively. Unit 3 is a 600MWe sodium-cooled fast breeder reactor (FBR) known as BN-600, which started operation in 1980. In addition to the electrical production, the unit produces district heating for the town of Zarechny. Unit 3 is the only unit to have been involved in the TACIS On-Site Assistance. A fourth Unit, also a sodium-cooled FBR (BN-800) has been under construction since 1987, but has suffered many delays, mainly due to the financial difficulties in Russia in the 1990s.
The steam-water circuit of sodium-cooled FBRs operates at higher temperatures than in PWR units, closer to the conditions in thermal power plants. In the BN-600 design, the steam-water circuits also perform safety functions related to the suppression of sodium-water reactions as well as being used for decay heat removal. The steam-water system is divided into 3 parallel circuits.
The components of the BN600 steam-water circuits are of standard type, which are approved for, and widely used in, conventional thermal power plants. Consequently, those components, including isolation valves, were developed and designed and their parameters and characteristics chosen in compliance with the thermal power plant design codes and standards which were in force at the time of BN-600 construction. Of about 3000 main valves in the steam-water circuits, 231 are safety-related system components. These valves were not in compliance with the NPP safety codes and standards applicable at the time of programming the present project.
Of the 231 safety-related valves, 144 are installed on the steam generator inlet/outlet lines. These valves perform the safety function ensuring rapid suppression of a sodium-water reaction in case of a leakage between the secondary sodium and steam-water circuits through the steam generator tubes.
In order to improve the reliability and safety of the BN600 steam-water circuits, it was decided to include a project in the TACIS 2005 Nuclear Safety programme to replace the existing 231 safety-related valves with new valves complying with the applicable NPP safety codes and standards.

The objective of the project was the provision and installation of new safety-related valves for the steam-water circuits of the Unit 3 as well as the tools required for cutting out the old valves, machining the pipes and welding the new valves in place.
The equipment provided by the Contractor included:
Lot 1A: Valves:
isolation valves subdivided in three (3) identical supply sets, the total number of valves supplied being 231 (3 x 77);
actuators for the supplied valves, including electrical connection of the actuators to the control / power circuits:
designated tools and devices required for valve and actuator installation and commissioning and maintenance;
pipe samples manufactured of material identical to the valve body material to develop the pipeline-to-valve joint welding and heat treatment procedures;
a monitoring system for gate seal and environment leak tightness.
Lot 1B: Tools:
4 sets of pipe cutting and bevelling machines and associated tools, suitable for cutting and bevelling pipes in one simultaneous operation;
4 welding machines capable of performing the following functions:
manual welding with inert gas non consumable electrode;
manual welding with consumable electrode;
semi-automatic welding with inert gas consumable electrode.

2 x 50 Hz industrial frequency transformer complete with a set of induction heaters of different standard sizes for thermal (heat treatment) applications.
The scope of equipment supply also included spare parts and consumables for the valves and actuators, for the leak tightness monitoring system and for the tools.
In addition, the scope of supply included documentation; design; manufacture; testing; delivery; certification; support to licensing; training of End User personnel and supervision of installation, site testing and commissioning.

The Call for Tender was launched in August 2006 and tenders were evaluated in November. The contract was signed with Sempell AG on 15 December 2006. The kick-off meeting was held at Beloyarsk NPP in February 2007.
The tools for valve replacement were procured and shipped to Russia on 6 June 2008 following receipt of the authorisation for tax free importation. The equipment arrived at Beloyarsk NPP site on 16 June. Training courses for Beloyarsk NPP personnel on the use of the tools were provided in December 2008.
The contractor prepared the detailed documentation packages required for the valves licensing process. Preparation of the documentation, its review by the regulatory authorities and the incorporation of comments took place between February 2007 and June 2008.
Head sample testing took place from April to October 2008.
The manufacturing and factory acceptance testing (FAT) of the first set of 77 valves was completed in December 2008 and the valves were shipped to Yekaterinburg, arriving at the customs premises on 22 January 2009. Customs clearance was completed by 26 February. Installation of the valves, under the supervision of the contractor, took place from 5 April to 20 May, during the Spring 2009 outage. Defective actuators discovered on two valves were replaced at the end of May. Following testing and commissioning, the first Provisional Acceptance Certificate (PAC) was prepared and signed in September 2009.
Manufacturing of the second set of valves was completed in November 2009 and FAT took place in December. The valves were delivered to Beloyarsk NPP on 25 January 2010 and were installed, tested and commissioned during the period April – June. The related PAC was issued on 27 July 2010.
Manufacturing and FAT of the third set of valves took place in September/October 2010. The valves were delivered to Beloyarsk NPP in February 2011 and were installed, tested and commissioned during the period April – June. The related PAC was issued on 27 August 2011.
The Final Acceptance Certificate was signed in September 2013 following satisfactory completion of the warranty period.