Precautions For Installing Inlet Pipes

When installing the water inlet pipeline, the degree of the segment may be upward or upward

This will gather air in the inlet pipe, reduce the vacuum degree of the water pipe and centrifugal pump, and lower the suction head of the centrifugal pump, resulting in a decrease in water output. The accurate approach is: the degree section should be slightly inclined towards the direction of the water source, not to a certain extent, and should not be lifted upwards.

There are many elbows used on the inlet pipeline

If more elbows are used in the inlet pipeline, it will increase local water flow resistance. And the elbow should turn in the vertical direction, and it is not allowed to turn in the degree direction to avoid gathering air.

Large diameter centrifugal pump with small water pipe for water supply

Many people believe that this can increase the actual head of the centrifugal pump, where the actual head of the centrifugal pump is equal to the total head minus the lost head. When the model of the water pump is determined, the total head is constant; The decrease in head mainly comes from pipeline resistance. The smaller the pipe diameter, the greater the resistance, and therefore the greater the loss of head. Therefore, reducing the pipe diameter not only fails to increase the actual head of the centrifugal pump, but also decreases, leading to a decrease in pump efficiency.

Similarly, when a small diameter water pump uses a large water pipe to pump water, the actual head of the pump will not decrease. Instead, the loss of head will be reduced due to the decrease in pipeline resistance, resulting in an increase in actual head. Some experts also believe that when using a large water pipe to draw water from a small diameter water pump, it will greatly increase the motor load. They believe that as the pipe diameter increases, the water in the outlet pipe will exert greater pressure on the pump impeller, thus greatly increasing the motor load. Little did they know that the magnitude of liquid pressure is only related to the height of the head, and is not related to the cross-sectional area of the water pipe. As long as the head is constant, the size of the impeller of the water pump remains unchanged. Regardless of the pipe diameter, the pressure acting on the impeller is constant. However, as the pipe diameter increases, the water flow resistance decreases, leading to an increase in flow rate and an appropriate increase in power consumption. But as long as it is within the rated head range, the water pump can work normally no matter how the pipe diameter is increased, and it can also reduce pipeline losses and improve water pump efficiency.

The water pump inlet is directly connected to the elbow

This will cause uneven distribution of water flow when entering the impeller through the elbow. When the diameter of the inlet pipe is larger than that of the water pump inlet, an eccentric variable diameter pipe should be installed. The flat part of the eccentric reducer should be installed above, and the inclined part should be installed below. Otherwise, gathering air will result in a decrease in water output or inability to draw water, and there will be a sound of impact. If the diameter of the inlet pipe is equal to that of the water pump inlet, a straight pipe should be added between the water pump inlet and the elbow, and the length of the straight pipe should not be less than 2-3 times the diameter of the water pipe.

The lower section of the inlet pipe equipped with a bottom valve is not vertical

If installed in this way, the valve cannot self seal, causing water leakage. The accurate installation method is to install the inlet pipe with a bottom valve, and the next section should be vertical. If vertical installation is not possible due to terrain limitations, the angle between the water pipe axis and the degree surface should be at least 60 °.

The position of the inlet of the inlet pipe is incorrect

When the inlet depth of the inlet pipe is not enough, it can cause vortices on the water surface around the inlet pipe, affecting the inlet and reducing the water output. The accurate installation method is: the inlet depth of small and medium-sized water pumps shall not be less than 300-600mm, and that of large water pumps shall not be less than 600-1000mm.

Please ensure that the water outlet is above the normal water level of the water tank

If the outlet is above the normal water level of the water tank, although the pump head is increased, the flow rate is reduced. If, due to terrain limitations, the water outlet must be higher than the water level of the water tank, elbows and short pipes should be installed at the pipe outlet to make the water pipe a siphon type and lower the height of the water outlet.