Reconstruction of pumping station No.7 «BashRTS»

LLC «Bashkir Heat Distribution System»

LLC «BashRTS» was established in December 2005. The company provides heat to eight cities in the Republic of Bashkortostan, including Ufa, Blagoveshchensk, Sterlitamak and others. It is a subsidiary of LLC «Bashkir Generation Company».

Bashkir Heat Distribution System serve 26 boiler houses, 304 central heating stations (TSC), 21 pumping stations. The total length of highways and quarterly networks in the two-pipe calculation for 2017 is 1480 p.km. The installed electric and thermal capacity of LLC «BashRTS» is 24 MW and 3587.45 Gcal/h, respectively.

Ufa is a rapidly developing city with active housing development. To meet the growing demand for heat, the existing heating networks are being modernized and new ones are being constructed in accordance with the approved «Heat supply scheme for the urban district of Ufa for the period until 2028».

Fig. 1. LLC «Bashkir Heat Distribution System», Ufa

Reconstruction of the pumping station

In 2014, began a project on the reconstruction of the feeding pump station No. 7 on the Novogornaya Street in Ufa. The existing building of the pumping station No. 7 is located in a separate building and is intended to maintain the hydraulic consumption mode in the heating season from the heating mains TM-30 and TM-31.

Currently, three pumping units are installed at the pumping station (2 in operation, 1 in standby), СЭ 2500-60 (2500 m3/h, H = 60 m) with electric motors ДАЗО4-400Х-4У1 (630 kW, 1500 rev/Min, 6 kV).

After the reconstruction, it is planned to increase the pump station productivity by 20%, and the pressure by 8%, while the electric drive capacity should remain at 630 kW.

The specialists of LLC «EnergoFront» had a serious task to find a technical solution for pumping units that would increase the plant's operational parameters (flow rates from 5000 to 6000 m3/h, pressure from 60 to 65 m) while maintaining the existing power of the electric motors. In this case, the pump units should have an efficiency of at least 84% and operate with a coolant with a temperature of up to 150°C.

Electro-pump aggregators DeLium

In the course of deep study of the technical side of the matter, our specialists proposed the delivery of three electric pump units DeLium D350-530A-Ш/Н-тт-Е УХЛ3.1 produced by JSC «HMS Livgidromash» with the following parameters: maximum flow 3000 m3/h, pressure 65 m, electric motor power 630 kW 6kV.

Fig. 2. DeLium double suction pump

The DeLium series is a new generation of double entry pumps with a horizontal body connector. The pumps are designed taking into account modern requirements for power consumption, reliability and long operation period and have the following design peculiarities and advantages:

1. Optimized hydraulics of the flowing part with maximum efficiency;

2. A body made of high-strength cast iron with nodular graphite or stainless steel with an internal pressure of up to 25 kgf/cm2;

3. Shaft completely insulated from the pumped liquid;

4. Single or double face seals;

5. Suction and delivery nozzles made "in line";

6. Double-coil tapping spiral, reducing the radial load on the rotor and bearings, which significantly increases their resource;

7. Standard or reinforced bearings, bearings service period - not less than 100 000 hours;

8. A wide range of models (more than 45 sizes) and the use of at least two interchangeable impellers for a single body size allow selecting the pump for any task within the feed range from 80 to 10,000 m3/h and pressure from 5 to 200 m.

Fig. 3. General view of the pump unit DeLium D350-530A

To confirm the high demands on the temperature of the network water, the body of the pump unit D350-530A-Ш/Н-тт-Е УХЛ3.1 will be made of high-strength cast iron with nodular graphite to a working body pressure of 25 kgf/cm2 (corresponds to the pressure of hydro-testing of heat networks), impeller material - stainless steel. Double face seals are also used.

The pump and the electric motor installed on a common frame and connected by means of a plate elastic coupling. The pump set is equipped with a complete set of control equipment: temperature sensors for pump and motor bearings, temperature sensors for motor coil and hardware of the stator of the electric motor, vibration sensors for pump bearings and electric motor. Modern hydraulics of the pump provides high efficiency in the nominal operating mode with a flat characteristic. High efficiency rates significantly affect the reduction of electricity costs, the payback period of new equipment is shortened.

Fig. 4. Performance characteristics of the pump unit DeLium D350-530A

To simplify the start conditions and exclude the possibility of water hammering, it was decided to equip the pump units with soft starters one per unit with a common control cabinet.

Devices of smooth start «RU-DRIVE SMV-6075»

After a deep analysis of the task, specialists of LLC «EnergoFront» proposed the soft starters «RU-DRIVE SMV-6075» with the control cabinet ПОТОК-ШУ produced by LLC MC «IED-Holding».

Fig. 5. Soft starter RU-DRIVE SMV-6075

«RU-DRIVE SMV» is a complex and highly reliable soft starter (SCP) designed for use with standard three-phase asynchronous high-voltage motors with squirrel-cage rotor. SCP provides an optimal way to reduce current and point during engine start-up.

The SCP starts the motor by applying a slowly increasing voltage to it, providing soft start and smooth acceleration with the minimum current required to start the engine. The second generation of digital microprocessor technology provides unique capabilities for pump control, reliable motor protection and information retrieval from the analog output.

By changing the applied voltage to the stator of the engine in a controlled mode, the effect on the mechanism and the supply network is eliminated. The hardware capabilities of «RU-DRIVE SMV» provide reliable protection of the motor in all operating modes: start, stop, continuous operation. In the «RU-DRIVE SMV» devices, thyristor starting using light triggering technology is realized, in which the thyristors located one after the other are sequentially switched. At the same time, their high reliability is ensured. Switching of SCP devices RU-DRIVE SMV-6075 and the control cabinet of the ПОТОК-ШУ is carried out by the communication protocols Modbus and Ethernet.

The technical solution for the DeLium D350-530A pumping units, offered by LLC «EnergoFront», fully complied with the requirements of the Terms of Reference and surpassed the offers of foreign competitors due to:

➢ increased permissible load on the nozzles;

➢ reduced dimensions of the pump unit;

➢ permissible coolant temperature up to 150°;

➢ domestic production of the pump unit, including pump casting and electric motor;

➢ the possibility of participation of the Customer's representatives in the factory tests;

➢ availability of spare parts and service maintenance;

➢ installation supervision and commissioning works of our company specialists.

Currently, the equipment is located at the plant of JSC «HMS Livgidromash». Before delivery to the Customer, the pump units will pass a series of factory tests, the purpose of which is to confirm the design parameters of the pump operation.

The initial delivery time of the pump set was 6 months, but due to the urgent need to finish the construction of the pumping station in October 2017 and at the request of LLC «BashRTS», our company agreed to reduce the production time at the plant by 2 months. It was achieved thanks to the close cooperation of the specialists of LLC «EnergoFront» and JSC «HMS Livgidromash». A new priority production schedule was developed, with the planned delivery date - at the end of August 2017, due to which the commissioning of the pumping station will take place at the appointed time.

After the equipment is delivered, the specialists of the Service Department of LLC «EnergoFront» will provide a range of services for the supervision of the installation and commissioning of pumping units.

Achievements: The supplied pump units were designed to meet the high technical requirements of the Customer. The introduction of this equipment, including a soft start system, is designed to solve the main task - increasing the capacity of the pumping station by 20% and the pressure by 8%, while the power of the electric drive (630 kW) will be maintained. The design of the pump will ensure reliable operation at a coolant temperature of up to 150°C. After the delivery of the equipment, the service engineers of LLC «EnergoFront» will conduct works on installation supervision and commissioning.

Case direction: equipment modernization

Equipment: Mains electro pump units DeLium D350-530A-Ш/Н-тт-Е УХЛ3.1 with electric motor А4-400У-4М У3 in quantity of 3 pcs. with soft starters and control cabinet RU-DRIVE SMV-6075