What Are The Water Filling Methods Of Centrifugal Pumps

There are two main methods of water filling before starting: one is to use the assembly bottom valve to fill water, and the bottom valve is a one-way valve, which is installed at the inlet of the water inlet pipe, and the disadvantage of this method is that the head loss of the bottom valve is large, which affects the device efficiency of the water pump; The other is the bottomless valve water filling, the biggest advantage of this method is energy saving, compared with the pumping station with a bottom valve can save energy by 10%~15%. The following describes several water filling methods for centrifugal pumps for users to choose when running the pump.

■Self-diversion and water filling method: For the semi-submerged pump room (that is, the pumping station where the elevation of the inlet pipe and the pump top are below the water surface of the inlet pool), the water can be introduced into the pump by itself without manual irrigation and diversion. The disadvantage of this pumping station is that the water absorption capacity of the pump is not fully utilized, and the installation elevation of the pump is reduced simultaneously, not only increases the excavation amount of the foundation, but also the operation management is also inconvenient; However, the advantages are also obvious, that is, it is easy to realize the automation of the pumping station and the timeliness is strong.

■Artificial water filling method: For small pumping stations with a diameter of less than 300mm inlet pipe, there is usually a bottom valve at the inlet of the inlet pipe, and the artificial water filling method is generally adopted, that is, from the special water-filling exhaust hole on the upper part of the pump casing, the water-filling funnel (or an upside-down ordinary bottle with the bottom of the bottle removed) is filled with water. For small pumping stations with an inlet pipe diameter of less than 300 mm, there is usually a foot valve at the inlet of the inlet pipe, and the pump can also be filled with water from the outlet of the pump (a pumping station with a short outlet line). Since there is no need to purchase other water filling equipment, this water filling method is relatively common in small rural pumping stations.

For the small pumping station without a foot valve, check valve and short pipeline, it can also be started while filling the pump with water from the outlet pipe mouth, so as to gradually bring out the air in the pump and the pipeline, and the pump can pump water normally after a few minutes of continuous water filling.

■Vacuum water tank filling method: For small pumping stations without foot valves, vacuum water tank filling method can be used. The vacuum water tank is a closed water tank welded with iron sheets, its volume is at least 3 times the volume of the inlet pipe, the position of the water tank installation should be as close to the water pump as possible, and the bottom height of the water tank should be slightly lower than the axis of the water pump. The height of the vacuum tank is generally 2 times the diameter of the tank.

Before the pump starts, fill the tank with water and seal it. After the water pump starts, the water pump enters the water from the vacuum box, and a certain vacuum is formed in the water tank due to the drop in the water level of the water tank, and the water in the water inlet pool will enter the water tank through the water inlet pipe under the action of atmospheric pressure, so as to form a water circulation and make the water pump start to operate normally.

■Jet pump water filling method: when the diesel engine is used to drive the water pump to pump water, the exhaust gas discharged by the diesel engine can be used to pass into the jet that communicates with the top of the water pump to pump and fill the water, so as to remove the bottom valve of the water pump. When the pump is started, the valve cover connected to the handle is closed, and the exhaust gas is ejected from the ejector, and the air in the pump is sucked out through the connecting pipe. After filling the water, open the valve cover and close the control valve. The advantage of this water filling method is that it makes full use of the power machine and improves the efficiency of the pumping station.