What influences maximum delivery head of a pump?
Table of Contents
What influences maximum delivery head of a pump?
Head is the height at which a pump can raise water up.” The head is somehow linked to the pressure. The more pressure the pump delivers, the higher the head will be.
How do I increase pump suction head?
How to increase suction head available
- Raise and maintain tank liquid level.
- Elevate supply tank.
- Reduce piping losses from too many fittings or too small diameter.
- Replace collapsed or compromised components.
- Clear solids from inside of pipes.
- Clear suction strainer.
- Replace corroded pipe.
How do you convert discharge pressure to head?
In simple terms, the mathematical constant 2.31 converts a unit of energy against gravity into a unit of force against any other area. This constant converts a foot of head of water into pressure: Head in feet of water divided by 2.31 equals pressure in psi, and pressure in psi times 2.31 equals head in feet.
How can we prevent cavitation in centrifugal pump?
Some tips to prevent cavitation due to vaporization include:
- NPSHa > NPSHr + 3 ft or more safety margin.
- Lower temperature.
- Raise liquid level in suction vessel.
- Change out pump type.
- Reduce motor RPM.
- Use impeller inducer.
- Increase diameter of the eye of impeller.
What causes cavitation in centrifugal pump?
Cavitation occurs when the liquid in a pump turns to a vapor at low pressure. It occurs because there is not enough pressure at the suction end of the pump, or insufficient Net Positive Suction Head available (NPSHa). As the liquid passes from the suction side of the impeller to the delivery side, the bubbles implode.
How do you calculate the discharge pressure of a centrifugal pump?
To calculate the discharge head, we determine the total head from the characteristic curve and subtract that value from the pressure head at the suction, this gives the pressure head at the discharge which we then convert to pressure.
Can we convert pressure head into head?
Pumps characteristic curves are often in head – feet or metres – and a conversion to pressure scales commonly used in pressure gauges – like psi or bar – may be required….Feet of Head Water to psi.
| Head (ft) | Pressure (psi) |
|---|---|
| 140 | 60.6 |
| 160 | 69.3 |
| 180 | 78.0 |
| 200 | 86.6 |
Why do we use head instead of pressure in centrifugal pumps?
The main reason for using head instead of pressure to determine the performance of a centrifugal pump is that the height of the fluid column is not dependent on the specific gravity (weight) of the liquid, while the pressure from a pump will change.
How can I increase the head diameter of the pump?
To increase the head of the pump you have increase the diameter of impeller not the motor. Usually to increase the discharge reduce the diameter and to increase the head increase the diameter of the impeller. Keep in mind this is the thumb rule
How does a parallel centrifugal pump work?
Parallel operation of centrifugal pumps is used to increase flow rate through the system. Pumps operating in parallel take their suction from a common header and discharge into a common discharge. While head changes only slightly, flow is almost doubled at any given point.
Do centrifugal pumps choke back to a small flow rate?
When pumping fairly cool water, these type pumps can be choked back to very small flow rates without any harm to the pump or motor. It is easy to tell if an engineer or pump installer truly understands what they are talking about if he or she understands this counter intuitive property of centrifugal pumps.