Maintenance of eight Mitsubishi, MTU and Cummins diesel generator sets for Rosatom

In 2020, the Techexpo service department provided a uranium mining company (a part of Rosatom state corporation) in Siberia with maintenance services for eight diesel gensets. Techexpo engineers maintained four 1000 kW diesel gensets with Mitsubishi S12R-PTA-S (Japan) engines, three 500 kW diesel gensets with MTU 12V 1600 G10F (Germany) engines and one 655 kW diesel genset with a Cummins QSK23G3 (US) engine. The scope of work included diagnostics, tests and maintenance.

Diagnostics:

• fan pulley and pomp pulley location; fan center normal operation and integrity;
• coolant system and fan belts integrity;
• water pump normal operation and integrity;
• no damper wobble, normal operation and integrity;
• coolant system and radiator hose integrity;
• electrolyte density and level, capacity of batteries, terminals, safety caps, power cables and jumpers, battery charger state;
• UPS in the 10 kV switchgear;
• Integrity of engine mounts, sensors,;x utility systems, fuel system valves;
• Integrity of engine systems hoses and clips, air piping nippers; tightening of fastening nuts, screws and engine/generator connections;
• 24V generator, electric starter;
• generator unit;
• Parameters of control panel, microprocessor protection, control keys;
• In-house outlets of radioelectronic units, electrical connection integrity
• AST when sendin;g emergency mode parameters to the device from an external source;
• switchboard automation selectivity;
• HV cells selectivity;
• switching devices; multiple switching on and switching off locking;
• free movement of switchgear draw-out elements; correct operation of switchgear mechanical locking;
• HV cells turning-on and turning-off activation;
• no mechanic damage of insulators in electrical devices;
• compliance with the primary switching circuits of 10 kV high voltage cells;
• compliance with the secondary switching circuits (operative circuits) of 10 kV high voltage cells;
• diesel genset exhaust system;
• current transformer connection correspondence to the scheme of metering circuits.

Maintenance:

• Fan belt replacement.
• Combustion engine heater boiler, antifreeze heating system cleaning.
• Combustion engine cooling system cleaning, coolant replacement.
• Radiator hose replacement, crankcase breather cleaning.
• Clearing battery terminals contacts, electrolyte density recovery when necessary.
• Engine sensors, container, diesel genset systems operation tests; calibration.
• Measuring generator unit winding electrical resistance with disconnecting control and signal lines. Comparing the measured data with factory characteristics.
• Combustion engine fuel system (including fuel facilities) complete service.
• Air filter replacement.
• Engine oil replacement. Oil and fuel filter replacement.
• Automatic fuel feed system maintenance, including automatic devices, valves, controllers considering the systems of fuel feed from diesel fuel tanks to the diesel fuel consumed tank of the diesel genset.
• Setting up engine security systems and automatic devices. ECM firmware upgrade and setting configuration files using license service software, nozzles and controllers firmware upgrade using license service software.
• 24V generator maintenance, electric starter maintenance.
• Checking expansion gaps in the combustion engine drive case, adjusting valve rocker arms.
• Generator unit maintenance: pulling generator bars (cable ends), measuring the temperature characteristics of generator bearings, aligning the generator against the engine, adjusting run-time parameters.
• Control panel firmware upgrade and setting config files using license service software. Setting the control system microprocessor security parameters.
• Removing the ATS cover plates to provide access to internal assemblies. Checking the seals of board doors, encasings and inlet bushes. Checking the integrity of ground wires, joint and connection efficiency. Checking the interaction between the elements, the correct interaction of protection relay, electrical automatic devices relay, control relay and alarm relay according to the ATS schematic circuit; adjusting.
• Fire and security alarm diagnostics. Setting a fire fighting line, inspecting fire and security system electronics.
• Measuring grounding resistance, checking metal-on-metal connection circuit between ground conductors and grounding elements.
• Setting and adjusting container temperature regulation and ventilation, adjusting vent valve operation.
• Checking ventilation and cooling system performance; container (power house) air supply system maintenance.
• Checking the integrity of electrical connections with a special heat measuring tool. Inspecting installed transformers.
• Checking the crankcase gas removal system.
• Setting the microcontroller undervoltage release device PR222DS/PD.
• Wire (cable) insulation checkup. Checking the reliability of contact connections (soldering) at terminals, bus branches, relay pins, test sets, resistors. Tightening of contacts and soldering inspection.
• Measuring input and group outgoing circuits loads by phases.
• Setting protection relay and automated devices relay SEPAM in diesel genset HV cells and 10 kV distributing board.
• Lubricating friction parts and switching devices contacts.
• Adjusting the mechanical part of switching devices, their contact pairs, gears and locking.
• Inspecting, checking and tightening of the contacts of 10 kV bus bridge, in diesel genset cells and distributing board
• Tightening of the contacts of primary switching circuits of 10 kV equipment.
• Tightening of the contacts of secondary switching circuits (operative circuits) of 10 kV HV cells.
• Setting the microprocessor protective relay package.

Tests:

• Diesel genset no-load running adjustment.
• Setting the diesel genset protocol translator/retranslator, making them operational.
• Checking the diesel genset heat balance during on-load operation.
• Checking the thermal state of automated devices with phase-by-phase current measurement for each in the units: auxiliaries board, high voltage cells.
• Carrying out individual tests for switchboard components.
• Setting synchronization control module MCS.
• Setting diesel genset parallel cold and on-load running with other same-type diesel gensets.
• Package diesel genset test with parameters observation (not less than 35 in each) in real time using a Scada complex.
• Single diesel genset cold running and equivalent load test

The Techexpo service department provided a 1-year guarantee for work performed and prepared test reports and certificates for all diesel gensets with photo and video evidence.