Supply of pumping equipment in the framework of the project «Reconstruction of Minsk TPP-3 with replacement of the outgoing line capacities of 14 MPa. 1st stage of construction»

In the energy system of the Republic Minsk TPP-3 plays an important role, operating since 1951. At that time, it was the first experience of launching high-pressure power equipment in Belarus. At present, installed capacity of the plant is 542 MW, including line of 14 MPa – 320 MW, unit of CCGT-230 – 222 MW. The branch of «Minsk TPP-3» of RUE «Minskenergo» provides about 25% of the energy needs of the capital of the Republic.

The reconstruction of the station with the replacement of the outgoing line capacities of 14 MPa takes place within the framework of the Industry program of development of the electric power industry for 2016 – 2020 years in order to improve the efficiency and increase the annual output of electric and thermal energy. Commissioning of the new turbine is planned in 2020.

Complete supply of the equipment for the reconstruction of the station (line of 14 MPa) is carried out by JSC «Ural turbine plant» in accordance with the agreement signed in February 2017 with RUE «Minskenergo».

JSC «Ural turbine plant» is one of the leading Russian engineering enterprises for the design and production of power equipment. Founded in 1938, the plant is a part of «ROTEC» holding and specializes in the production of steam turbines, service and modernization of steam and gas turbines. Currently, the plant manufactured and shipped turbine TP-115/130-12,8, heaters and condenser. The steam turbine of 115 MW capacity belongs to a new generation of turbines designed to replace the most mass serial turbine of the Ural plant — T-100. The turbine is designed using new calculation tools and modern materials.

«EnergoFront» company was faced with a task of selecting four vertical semi-submersible circulation pumps on the parameters: Q= 4235 m3/h, H= 29,5 m, temperature of pumped fluid – in the summer 33⁰ С, winter – 4⁰ C, mark of the bottom of forebay: - 5,470 m; complete with VFD.

In this case, the pumps had to meet the requirements of the supply range: 20-100% of the nominal value, as well as fall into the existing dimensions of the circulation pump. Each pump had to be able to work directly from the network, as well as be able to control the performance. VFD should have been able to be installed outdoors.

Having worked out several options for possible pumps manufacturers under the specified requirements, the pumps SNW 600-720 (Q= 4235 m3/h, H= 29.5 m), manufactured by KSB holding, equipped with electric motors produced by WEG, designed to work with frequency converters, were selected.

SNW pumps have a number of the following advantages:

• long-life bearing unit Residur®, lubricated by the pumped medium. No lubrication is required before the pump is put into operation. The bearing unit does not require maintenance and does not contaminate the pumped liquid;

• sealed bearing with the possibility of subsequent filling;

• minimization of shaft bending due to the fact that the impeller is installed between the bearings;

• inlet cone for best suction conditions;

• flexible coupling. Also during engine mounting, coupling and bearing are protected from contamination;

• compact coupling and bearing assembly. Minimization of wear in case of shaft run-out, imbalance and return forces;

• oil seal of the shaft: during the launch of a submersible pump, at first, in the chamber of the mechanical seal the emergence of air bubble is possible, it will cause damage to the mechanical seal due to friction (burn marks). In the oil seal, this effect is absent due to the use of graphite lubricant or teflon. The oil seal allows dry friction during start-up of the pump. Accordingly, KSV recommends the use of an oil seal instead of an end seal in these pumps to improve the reliability of the pump, its maintainability and efficiency in maintenance;

• maintenance-free, wear-resistant Residur ® bearing is also a shaft seal in EB mounting option;

• sleeve coupling in the shell without screw connection, thus independent of the direction of rotation. No corrosion due to the completely closed design;

• easy installation, the recess in the flange of the lamp relieves the installation of the engine.

To regulate the pumping units, a scheme of operation of VFD is selected: 1 VFD for 2 pumps with the possibility of switching from one to the second.

VFD will be installed in a block-modular building with its own ventilation system.

Explaining to the customer the advantages of KSB pumps, decision of «EnergoFront» on the proposed equipment has been recognized as the best. All technical aspects were agreed with the design institute and the General contractor.

Currently, the equipment is in production. Considering the importance of the project implementation, as well as the importance of strengthening ties between LLC «EnergoFront» and JSC «Ural turbine plant», «EnergoFront» company will make every possible effort to manufacture and supply pumping units within the specified time frame: in the 2nd quarter of 2019. Experts of «EnergoFront» will provide services for installation supervision and commissioning of the equipment supplied.

This project for «EnergoFront» has become another example of how, thanks to the company's many years of experience in implementing complex deliveries and selection of complicated equipment, established connections with factories and suppliers, it is possible to achieve an optimal result on the selection of equipment that meets the requirements of the project. The specialists of «EnergoFront» managed to solve several tasks simultaneously: pick up modern equipment and significantly optimize the costs of its purchase and installation. In this project, the company also implements its competences for the installation and commissioning of the equipment supplied.

Project achievements