Self Priming Pumps
A Self-Priming pump is a pump that is designed to be able to lift fluid from below its suction without the need of a foot valve, or hydraulic column of fluid in the suction line.
The pump operates with the aid of fluid in the pump volute. The self-priming pump uses an intelligent internal design that recirculates the existing water in the volute which evacuates the air out the discharge or the air release valve.
This continually creates a low pressure zone at the eye of the impeller which draws the fluid up the suction line until eventually the suction line and pump volute are full of the fluid. When they are full of fluid, which then allows the pump to work in dynamic operation similar to a standard centrifugal pump principal.
Self priming pumps are used in petrochemical, mining, water management, effluent and sewage processing, agricultural and industrial wastewater applications.
Types of self priming pumps:
Centrifugal pumps are used to transport fluids by the conversion of rotational kinetic energy to the hydrodynamic energy of the fluid flow. The fluid enters the pump impeller along or near to the rotating axis and is accelerated by the impeller, flowing radially outward into a diffuser or volute chamber (casing), from which it exits.
Common uses include water, sewage, agriculture, petroleum and petrochemical pumping. Centrifugal pumps are often chosen for their high flow rate capabilities, abrasive solution compatibility, mixing potential, as well as their relatively simple engineering.
Dosing pumps can be set to discharge exactly the quantity of dosing liquid required for the required application.
Applications include drinking and waste water treatment, industrial applications and the food and beverage industry
Positive Displacement Pump
The positive displacement pump provides an approximate constant flow at fixed speed, despite changes in the counter pressure.
Positive displacement pumps all pulsate, meaning that their volume flow within a cycle is not constant. The variation in flow and speed leads to pressure fluctuations due to resistance in the pipe system and in valves.