Modernized feeding pump ПЭ-580-185-5 at Verkhnetagilskaya GRES

Verkhnetagilskaya GRES is heat power station in Verkhniy Tagil( Sverdlovsk region), operation as part of JSC “INTER RAO-Electrogeneration”. The station was put in operation since May 29, 1956. The station consists of 11 energy units with total electric capacity 1497 MW and heat capacity-500 Gkal/h. The fuel is coal, axle oil, and gas (100%). The staff is 1119 people.

Drawing. 1 Verkhnetagilskaya GRES.

In July the tender to supply feeding pump without electric motor for energy unit 11 at Verkhnetagilskaya GRES was announced. Characteristics are as follows:

Besides, acc. to technical conditions the pump should be maintained on the existing basement of the former pump ПЭ-580-185-5, dismounted earlier, and located in the main building of boiler- and turbine section №2 at Verkhnetagilskaya GRES.

Drawing. 2 Feeding pump ПЭ-580-185-5

Specialists of JSC “EnergoFront” took all above mentioned into account as well as the requirements of the station to maintain the new pump on existing basement, and offered pump unit ПЭ-580-185-5 produced by JSC “Nasosenergomash” Sumy”. The pump is the newest model and it includes all latest achievements in the field of constructions and materials with the following modernization:

• optimal ratio of blades of turbine impeller and vanes in distributor-7/9 that improves vibration state of the unit via excluding of the first three harmonic components of exciting force operating on rotor and thus blade component of vibration frequency is removed -350 Hz, mean square value of vibration speed of bearing assemblies in rated duty- not more than 4,5 m/s, efficiency was increased by 2-3% ( pump efficiency is about 84-85%);
• end seal instead of groove ones, as was calculated in case of drain from balancing device to suction main will decrease by 4, 6 million kW/h of power for auxiliary connected with heating of cold condensate with temperature ≤ 40 °С in high pressure feed water heater 4,78 m3/h, that is in feeding drain in case of groove seals; and besides, deletion of cold water inside the pump( using end seals) that will improve heating of outside of pump case being in reserve;
• O-rings of impellers and slugs of cylindrical groove of balancing device is made from chrome- nickel wear proof alloy brand 60Х15МСЛ acc. to technical conditions ТУ У 29.1-05785448-002-2001; this alloy is substitution of КЭЧ 130Х15;
• Usage of seal of sealing washer made from thermal expanded graphite made by “UNICHIMTEK”( Moscow) to seal the main connector of pump( outside casing +pressure head), its usage will make the construction of unit easier for maintenance ( 15%) and decrease force for torque force studs of the main connection, and pressure in them;
• Construction of force studs was changed that gives the possibility to use hydraulic jacks( hydraulic keys) that decrease working time and speeds up the process of their torque and what’s more important provides high accuracy and uniformity of torque studs.
• Device of extraction of pump rotor to provide guaranteed clearance in end groove of balancing device at stand and start of the pump that will provide reliability of discharging gear.

Drawing. 3 Modernization of feeding pump ПЭ-580-185-5

After the modernization feeding pump ПЭ 580-185-5 has kept its characteristics in flow, head, rotation, suction head of vapour pressure, temperature of pumped medium and outline dimensions to the basement, inlet and outlet piping.

In the scope of delivery there also are set of spare parts and tools, operation manual to maintain start-up, and safe operation of the pump.

To prove reliability of the offered pumps to Verkhnetagilskaya GRES the following references were given: now pumps model ПЭ- 580 with modernized liquid end are operated at the following power stations: Zainskaya GRES, Nevinnomysskaya GRES, Abakanskaya TPP, Pavlodarskaya TPP, Nizhnekamskaya TPP-1.

Taking into account the requirements of technical task, high value of reliability and energy efficiency of the pump, and optimal cost of ПЭ-580-185-5 the offer from JSC “EnergoFront” was considered the winner in the tender.

Now the contract to supply feeding pump is being signed as well as placing the order at production . The delivery time is the beginning of March 2016.