CENTRIFUGAL PUMPING UNITS – ZBKIT-2-CNU-Q-H- U2-1А
Centrifugal installation ZBKiT represents an aggregated decision of centrifugal pump units including necessary equipment and electric part (including instrumentation and control equipment)
At installation of centrifugal pumps at pump station and their work on individual pipelines an assembly insert, return valve, shutoff valves, diffusor are installed on pressure head communications.
Pump stations are equipped with high-speed one- and multistage centrifugal pumps of high productivity (to 3000 m/h and more). Electric motors more are often used as a drive for the pumps. Stations are equipped with systems of centralised control and management.
The largest pumps are capable to pump over several thousand cubic metre of oil an hour. Each pump station provides certain speed of oil movement on its site, to the following station. Linear speed movements try to support within 1-1,5 l / second. Main pipelines are equipped with means of local automatics.
Vertical centrifugal pumps are intended for vertical installation by shaft position. The basic advantage of vertical pumps of type B is smaller size in the plan in comparison with horizontal ones and convenience of configuration for some types of pump stations. These advantages are especially essential for large pumps.
Example. To select water air ejector for filling with water of centrifugal pump with calculated lifting height //вс = 5 m. Diameter of lifting pipeline тр = 300 mm, its length = 20 m. Duration of filling of pump and lifting pipeline should not exceed 5 minutes Absolute pressure in the network of pump station is 0,45 MPa. This pressure was decided to use for work of ejector during operating time of pump station. If the basic pumps do not work, filling should be made by means of circulating installation with the centrifugal pump, water air ejector and a vacuum tank.
Application of adjustable drive considerably raises economic indicators of pump stations, economy of electric power reaches 10-15 %, Application of adjustable centrifugal pump allows to reduce number of pumps at pump stations. For the group of three-four working pumps it is enough to have one adjustable pump.
Vertical centrifugal pumps (with vertical shaft) are widely used at pump stations of the first lifting at big fluctuations of water level in the source, and also for lifting of underground waters from boreholes. Usually these pumps are connected directly to vertical electric motor.
Pump stations ZBKiT-2-ЦНУ-Q-H- У2-1a possess a set of advantages:
- Smooth start-up:
- Smooth start-up;
- Absence of hydroblow at switch-on;
- Minimisation of mechanical loadings;
- Setting of certain pressure and its maintenance on the set mark.
- Absence of “dry run”.
- Minimization of current overloads.
- Reliable protection against pressure differences.
- Economical expenditure of electric power.