Russia Manufactures Innovative Equipment for Turkey’s Akkuyu NPP
Atommash has manufactured a set of moisture separator-reheaters for the turbine hall of Unit 2 at the Akkuyu nuclear power plant under construction in Turkey.
For the first time, the plant produced the units in a horizontal configuration, combining the functions of several pieces of equipment in a single vessel. Digital modeling and advanced welding technologies reduced assembly labor intensity by as much as 27%.
An Unconventional Horizontal Configuration
Moisture separator-reheaters (MSRs) are large components of a nuclear power plant’s steam turbine auxiliary systems. Their primary function is to maintain the specified temperature and moisture content of the steam driving the turbine rotor blades – parameters that directly affect turbine efficiency and service life.
For the Turkish nuclear plant, engineers selected an unusual horizontal MSR configuration. The design reflects the layout of the steam turbine system in the turbine hall and the use of low-speed turbines. Within a single vessel, designers were able to combine the functions normally performed by two vertical units.
As a result, the power unit requires only two MSRs instead of the conventional four. The change in configuration has nearly halved the total amount of metal required for their manufacture. At the same time, the new design has improved the specified efficiency, reliability and cost-effectiveness of the steam path. Atommash is already launching serial production of equipment in the same configuration for subsequent projects.
The Role of Digital Modeling
Manufacturing equipment on this scale requires extremely precise engineering calculations. Each unit is 4.5 meters in diameter and more than 22 meters long, with a weight of up to 320 metric tons.
Digital modeling of component geometry significantly simplified preparations for manufacturing. Atommash engineers created precise three-dimensional models of the equipment. In a virtual environment, they worked through the assembly sequence, calculated metal shrinkage after welding and simulated heat treatment.
Digital twins allowed engineers to identify potential problem areas before production began. Process engineers optimized the cutting of rolled sheet metal and selected the most effective processing parameters. Components no longer have to be fitted in place, while the alignment of assemblies during trial assembly at the plant is now close to ideal.
Advanced Welding Technologies
Joining the thick-walled vessel components remains one of the most demanding operations in nuclear equipment manufacturing. Welds must remain completely leak-tight and withstand cyclic loads throughout the operating life of the power unit.
Atommash has introduced a range of innovations in automatic and mechanized welding. The plant uses advanced welding materials and specialized equipment. During production of the MSRs for the Turkish project, control algorithms for the welding heads continuously monitored arc parameters and adjusted the tool path in real time.
As a result, comprehensive digitalization and automation of production processes reduced assembly labor intensity by an average of 8.4%. At some of the most complex stages, including vessel fabrication and nozzle welding, labor intensity fell by as much as 27%. This allowed the plant to accelerate its production program while freeing up skilled welders for other work.
Export Projects and Manufacturing Capacity
The production of the innovative MSRs demonstrates the Russian nuclear engineering industry's capabilities in manufacturing non-standard equipment. Turkey's Akkuyu NPP is being built using Russian technology and will have four Generation III+ VVER-1200 reactors. It is the world's first nuclear power project implemented under the Build-Own-Operate model.
Rosatom's Mechanical Engineering Division is supplying the Turkish plant with a complete package of primary- and secondary-circuit equipment. Atommash has already shipped reactor pressure vessels, steam generators and main coolant pipeline components for the first units to the site. In parallel, the plant is manufacturing equipment for Akkuyu Units 3 and 4.
The experience gained in designing and manufacturing horizontal moisture separator-reheaters is building a new technological foundation, including the potential to export specialized equipment. That, in turn, strengthens the Russian corporation's position in the global nuclear technology market.
