Pump Types And Materials

Single-stage volute centrifugal pumps, followed by multistage vertical turbine diffuser pumps in a suction tank, are most commonly used for domestic water pressure booster systems. The volute pumps can be end-suction with a vertically split case, double-suction with an axially split case, or in-line. For high-pressure service, two-stage axially split case pumps or multistage vertical turbine pumps may be selected.

In selecting the type of pump best suited for the application, such inherent characteristics as low-flow recirculation, low-flow cavitation, high-flow cavitation, steepness of the pump curve, noise, and operating efficiencies should be evaluated. These factors are discussed in Subsection 2.3.1.

The most often discussed factor in booster application is low-flow recirculation. Low pump flow conditions do occur; they cannot be completely designed out of the system. Most well-designed small pumps with positive (above atmospheric) suction pressure can operate safely in the low-flow region, with the only point of concern being water temperature rise at or near shutoff flow. Should radial thrust be a major consideration, double-volute pumps or diffuser (vertical turbine) pumps offer advantages.

Vertical pumps generally require less space. Pumps may be close-coupled to their drivers, or, if not, a coupling requiring careful alignment is required. Close-coupled pumps may require less maintenance, as there are no pump bearings. Shaft sealing may be either packing or mechanical seal.

All pumps and drivers in packaged units are mounted on a common steel frame, but individual bases for each pump and driver may be necessary for larger units.

The materials of construction for pumps, valves, and piping should be suitable for the water quality and conditions furnished to the system. Because water impurities vary from location to location, careful analysis is recommended. Federal and local agencies, such as the Food and Drug Administration, may also prescribe allowable materials.

Renewable Energy Eco Friendly

Renewable Energy Eco Friendly

Renewable energy is energy that is generated from sunlight, rain, tides, geothermal heat and wind. These sources are naturally and constantly replenished, which is why they are deemed as renewable.

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