Supply of the internal housing of the PE720-185-4 boiler feed pump with a rotor and the 4AZM 6300/6000 UHL4 electric motor (IAEL.528621.001) for the Cherepetskaya State District Power Plant named after. D.G. Zhimerin" JSC "Inter RAO - Electric Power Plants".

“Cherepetskaya State District Power Plant named after D. G. Zhimerin” is located in the city of Suvorov, Tula region. Installed thermal power: 172 Gcal/h. 
“Cherepetskaya State District Power Plant named after D. G. Zhimerin” is the first powerful steam turbine power plant in Europe, designed for ultra-high steam parameters (pressure 170 atmospheres, temperature 550°C). Currently, the installed capacity of the station is 450 MW.

As part of the target reliability improvement program, the Cherepetskaya State District Power Plant named after D. G. Zhimerin branch assigned the EnergoFront company task for the supply of a PE 720-185-4 boiler feed pump unit with an electric motor. This unit was supposed to be put into emergency reserve.

Taking into account the cost of the unit, during a deep study of the technical side of the issue, EnergoFront specialists proposed a solution to optimize the station’s costs for purchase and repair. The EnergoFront company will supply to the station a modernized internal casing of the PE720-185-4 boiler feed pump with a rotor and a 4AZM 6300/6000 UHL4 electric motor driving this pump, which will improve the efficiency and reliability of existing equipment.

Dimensional sketch of the modernized internal pump housing of the boiler feed pump PE 720-185-4

The upgraded inner housing has the following advantages:

• highly efficient flow part with increased efficiency;

• optimized first stage design to resist erosive wear;

• low noise and vibration levels of the pump;

• increased resource due to the use of new structural materials;

• preventing damage to the pump housing pressure cover by using washout protection in the hydraulic unloading unit.

The supplied internal housing for the PE720-185-4 boiler feed pump will be installed in its original location without additional modifications or changes in overall and connection dimensions specified in drawing RN17.029.101.00SB.

Dimensional sketch of electric motor 4 AZM 6300/6000 UHL4

Technical characteristics of electric motor 4 AZM 6300/6000 UHL4:

• electric motor power – 6300 kW;

• voltage – 6000 V ± 10%;

• speed – 3000 (sync.) rpm;

• frequency – 50 Hz;

• direction of rotation, when viewed from the working end of the shaft (i.e. from the side of the driven mechanism), right clockwise or left counterclockwise – 50 ± 2.5%;

• standards - GOST R 52776-2007, TU16-528.339-87 (IAEL.528621.001);

• rated current – ​​690 A;

• starting current / rated current (multiplicity) – 5.9;

• power factor – 0.9;

• Efficiency – 97.6%;

• the multiple of the initial rotating starting torque is 0.95;

• ratio of maximum rotating torque – 2.2;

• version - 1M1001;

• degree of protection: motor – IP-44, terminal box – IP-55, external fan – IP-20;

• cooling –  ICW37A71 according to GOST20459;

• operating mode – S1;

• thermal insulation/heat resistance – class F - GOST 8865;

• stator insulation – thermosetting “Monolit-4” type;

• plain bearings with a forced lubrication system;

• weight – 11,700 kg; 

• dynamic balancing of the rotor on a special machine;

• installation altitude – up to 1000 m above sea level;

• accessories: resistance thermal converters with NSKh Pt100 using a three-wire connection circuit TS1388/1/-/2xPt100/-50+200/30/5/5/KMMFE/V/No.5/GP and TS-1288/2-/2xPt100/-50+200/100/8/3/KMMFE/V/No.5/GP TU 4211-012-1328997-2014;

• warranty – 3 years;

• service life – at least 30 years;

• number of starts – 2 from cold, 1 from hot, total number of starts over the service life – 7500.

The solution proposed by EnergoFront made it possible to reduce the station's costs for the purchase of backup equipment, since the assembled unit is much more expensive than the internal housing and engine. From the list of project achievements, I would also like to note the reduction in time for emergency replacement and downtime of the unit, since replacing the internal housing of the boiler feed pump is much easier and faster than replacing the assembled unit. And if the electric motor fails, it will be possible to replace only the electric motor without disassembling the backup unit.

The technical solution developed by the EnergoFront company is optimal for the customer in terms of efficiency and the achieved effect.

Project achievements