Loviisa nuclear power plant, Finland

The year 2001 represented a major milestone, when we supplied the first 104 pairs of fuel assembly components (top and bottom nozzles) as well as 104 shrouds through our customer, then the BNFL Company, today the British company Westinghouse. By 2007, we had delivered a total of 735 pairs of top and bottom nozzles and 741 shrouds. In 2001, we also supplied Loviisa NPP with the MKM-3 control rod drive tension meter.

In 2003, we produced for the Loviisa NPP the EZ 650 flange joint stud tensioner. In 2005, we produced another special tensioner for the flange joints of neutron flux and temperature measurement nozzles. Both tensioners were completely developed by our colleagues at ŠKODA JS, and we managed to replace the originally manual tightening of the said flange joints using torque wrenches with an electronically controlled device, which reduced the labor intensity of flange joint tightening, thus significantly slashing the time required for this task and thus also the power plant’s outage.

In 2020, we delivered a new EZ 650 PRO tightening unit and a modernized MKM-3/M device for the control rod drive torque measurement to FORTUM for the Loviisa NPP in Finland. The electrically controlled tightening unit EZ 650 PRO is designed for tightening and loosening the joint of the control rod drive and the VVER 440 reactor drive housing. Its design allows performing these operations in the upper unit of the shut-down reactor and in the upper unit maintenance station. The control and the parameter setting take place via the touch screen together with the USB interface enabling importing or exporting the sets of working parameters of the tightening unit and exporting the measured values of tightening torques.

Since 2010, we have also been providing the Loviisa NPP with regular supplies of intermediate rods for control rod drives. By 2020, we had produced and delivered a total of 91 of them.

For the Loviisa NPP, ŠKODA JS also supplies a wide variety of spare parts for the reactor control drives, such as coolers, labyrinth shells, special control valves, bearings, toroidal tubes, pole extensions and others.

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