Cont

Have any Questions?

+86 18626835909

May 11, 2022 View:

What Is The Relationship Between Pump Discharge Pressure And Head

The head and pressure of the pump are important performance parameters of the pump, and there is an inextricable relationship between the pressure and the head, which can help us to use the pump better. Today Ace lobe pump to understand the relationship between pump discharge pressure and head.

I. What is discharge pressure

Pump discharge pressure refers to the total pressure energy (unit: MPa) of the liquid being sent through the pump. It is an important symbol of whether the pump can complete the task of conveying liquid, for the discharge pressure of the pump may affect the user production can be normal. Therefore, the discharge pressure of the pump is designed and determined according to the needs of the actual process.

According to the needs of the production process and the requirements of the manufacturing plant, the discharge pressure is expressed in the following ways.

1、Normal operating pressureThe pump discharge pressure required when the enterprise production is operated under normal working conditions.

2、Maximum required discharge pressureThe pump discharge pressure required for the possible working conditions when the production working conditions of the enterprise change.

3, the rated discharge pressure pump manufacturer specified and guaranteed to achieve the discharge pressure. The rated discharge pressure should be equal to or greater than the normal operating pressure. For vane pumps it should be the discharge pressure at the maximum flow rate.

4, the maximum allowable discharge pressure pump manufacturer according to the performance of the pump, structural strength, the power of the original motor to determine the maximum allowable discharge pressure value of the pump. The maximum allowable discharge pressure value should be greater than or equal to the maximum required discharge pressure, but should be lower than the maximum allowable working pressure of the pump pressurized components.

II. Pump head H

The head of a water pump is the energy obtained per unit weight of liquid after passing through the pump. It is expressed in H, in m, the height of the liquid column of the discharged liquid.

The effective energy obtained per unit pressure of the liquid passing through the pump, also known as the total head or full head. Can also be said to be at the outlet of the pump and the inlet of the liquid has the energy difference. But it must be stated: it is only related to the performance of the pump itself, and not with the inlet and outlet pipeline. The unit of head is Nm or m liquid column height.

Head is the key performance parameter of the pump, according to the needs of the petroleum and chemical process and the requirements of the pump manufacturer, the pump head also has the following methods of expression

1, the normal operating head enterprise under normal production conditions, the pump discharge pressure and suction pressure determined by the pump head.

2, the maximum required head enterprise production working conditions change, may need the maximum discharge pressure (suction pressure has not changed) when the pump head.

3, rated head rated head is the rated impeller diameter, rated speed, rated suction and discharge pressure under the pump head. Is determined by the pump manufacturer and to ensure that the head, and this head value should be equal to or greater than the normal operating head. Generally take its value equal to the maximum required head.

4、Closing head is the head of the pump when the flow rate is zero. It is the maximum limit head of the pump, and generally the discharge pressure under this head determines the maximum allowable working pressure of the pump body and other pressurized components.

Three, the pump discharge pressure and head conversion formula

The formula for converting pump discharge pressure to head: H=(p2-p1)/g.

where P1 the outlet pressure of the pump, Pa.

P2 a pump inlet pressure, Pa.

Density of the liquid, kg/m3.

g acceleration of gravity, m/S2.

It can be seen that the relationship between pump discharge pressure and head is that the length of the pump head depends on the size of the pump discharge pressure.