Ever stared down at a pump that just would not get going, the dreaded airlock preventing it from doing its job? Those who have experienced the frustration of manually priming a pump may appreciate the ingenuity of self-priming pumps.
These devices are designed to automatically remove air from their suction line and pump casing, allowing them to start pumping liquid even when they are not initially filled. This eliminates the need for manual intervention, saving time, effort and potential headaches.
How Do Self Priming Pumps Work?
Self-priming pumps typically employ a special design in their pump casing. This design creates a mixing chamber where air and liquid can mix. As the impeller rotates, this mixture is discharged. The heavier liquid then separates and returns to the pumping chamber, while the lighter air is vented out through the discharge port. This process continues until all the air is evacuated and the pump is fully primed with liquid.
Why Choose a Self-Priming Pump?
The benefits:
- Convenience: No manual filling or venting is required.
- Timesaving: Pumping operations can be started faster.
- Reduced risk of damage: Self-priming pumps are less prone to damage caused by dry running compared to standard centrifugal pumps. This design can contribute to a longer life span and potentially reduce the frequency of repair needed.
- Versatility: These pumps are useful in many industries and applications where the liquid source is below the pump level or where air can easily enter the suction line.
Common Applications for Self-Priming Pumps
These applications include:
- Sewage
- Grit and debris
- Steel mills
- Irrigation
- Textiles
- Dewatering
- Slurries
While self-priming pumps offer many advantages, it is important to note that they typically have a lower efficiency compared to standard centrifugal pumps when fully primed. They also have a maximum suction lift capability, meaning they can only draw liquid from a certain vertical distance below the pump.
Self-priming pumps are a valuable tool for a wide range of applications where ease of use and reliable startup are crucial.
