Overhaul of the VOITH 682 SVNL 33G hydraulic coupling at Kharanorskaya GRES

Kharanorskaya GRES is the largest thermal power plant in Eastern Transbaikalia and the most powerful station in the Trans-Baikal energy system. The station makes a huge contribution to the development of the region. Electricity generation at Kharanorskaya GRES is more than 2.7 billion kW/h per year.

Due to the planned shutdown of the Kharanorskaya GRES power unit No. 3, it is necessary to ensure that the VOITH 682 SVNL 33G hydraulic couplings operated as part of responsible mechanisms - PEN-3A, PEN-3B - are repaired as soon as possible.

Major repairs of the equipment were carried out in accordance with the requirements of the VOITH TURBO manufacturer's guidance documents and as part of scheduled maintenance of the equipment in order to restore operability and increase the reliability of the unit.

All maintenance work performed on the territory of Kharanorskaya GRES was provided by the technical guidance of certified EnergoFront service engineers.

The task of EnergoFront was to ensure the implementation of a set of measures for the overhaul of VOITH 682 SVNL 33G hydraulic couplings as part of:

• dismantling of hydraulic couplings and disassembly of the oil system of the units;

• packing and transportation of hydraulic couplings to a specialized repair site;

• disassembly of the hydraulic coupling, assessment of the technical condition;

• replacement of components, elimination of other identified defects;

• assembly of hydraulic couplings and preparation for return transportation;

• installation of hydraulic couplings in the unit at the facility and assembly of the oil system;

• commissioning and re-commissioning of feed pump units.

Major repairs of VOITH 682 SVL 33G hydraulic couplings were carried out at a specialized repair site equipped with specialized tools and with the involvement of the manufacturer's specialists.

A number of works have been performed during the repair of the hydraulic couplings:

• disassembly and direction of defects – deterioration of bearings, seals and gears has been detected;

• replacement of worn–out components - original VOITH TURBO spare parts are installed;

• assembly – setting the gaps and fitting the parts;

• balancing – dynamic balancing has been performed to minimize vibrations;

• hydraulic testing – checking of tightness and operating pressure;

• technical reports – preparation of accounting repair documentation;

Carrying out repair work at a specialized site made it possible to carry out the work efficiently and in a short time.

At the final stage of repair work at Kharanorskaya GRES, hydraulic couplings were installed on the frame of the PEN-3A and PEN-3B feed pumps, which underwent major repairs, the equipment was re-strapped and adjacent systems were connected with hydraulic oil replacement, and the shafts of the units were centered.

Two units of the PEN-3A and PEN-3B feed pumps were launched on time agreed with the Customer. The feeding units were brought to operating parameters together with the start-up of power unit No. 3 after the completion of repair work.

The results of the repair work will ensure confirmation of the reliability of the operation and the required operating performance of the Kharanorskaya GRES feeding units for the next inter-repair period.

Project achievements