Centrifugal pumps application range

These booster pump stations usually consist of a centrifugal pump (capacities ranging between 0.6 and 4 mVs) with a diesel or electric drive mounted on a skid or trailer for on land applications or on a pontoon when used over water To avoid the development of a vacuum in the pipeline it is imperative that the position of... 

Fluid power encompasses most applications that use liquids or gases to transmit power in the form of mechanical work, pressure and/or volume in a system. This definition includes all systems that rely on pumps or compressors to transmit specific volumes and pressures of liquids or gases within a closed system. The complexity of these systems range from a simple centrifugal pump used to remove casual water from a basement to complex airplane control systems that rely on high-pressure hydraulic systems. 

The centrifugal pump is the type most widely used in the chemical industry for transferring liquids of all types—raw materials, materials in manufacture, and finished products—as well as for general services of water supply, boiler feed, condenser circulation, condensate return, etc. These pumps are available through a vast range of sizes, in capacities from 0.5 m% to 2 x 10 mVh (2 gal/min to itf gal/min), and for discharge heads (pressures) from a few meters to approximately 48 MPa (7000 Ibftin ). The size and type best suited to a particular application can be determined only by an engineering study of the problem. 

On balance, centrifugal pumps always should be considered first in comparison with reciprocating or rotary positive displacement types, but those do have their places. Range of applications of various kinds of pumps are identified by Figure 7.14. 

Centrifugal pumps have a wide range of application for transferring fluids in industrial operations. Centrifugal pumps are reliable and mechanically simple. Many chemical plants and refineries have hundreds of centrifugal pumps of various sizes conveying sundry liquids and slurries. These vital workhorses are used for water, flammable liquids, acids, caustics, and most other fluids. 

Continuous product flows under high-pressure conditions (p > 30 MPa) can only be achieved with hermetic centrifugal pumps. Although the two drive systems that can be used - the permanent magnet coupling and the asynchronous canned motor - have the same mode of operation, they differ in their applications and their safety ranges. 

The best solution to problems caused by TSH variations is to prevent the variations. While it is not possible to completely eliminate them, the operating practices for centrifugal pumps should limit operation to an acceptable range of system demand for flow and pressure. If system demand exceeds the pump s capabilities, it may be necessary to change the pump, the system requirements, or both. In many applications, the pump is either too small or too large. In these instances, it is necessary to replace the pump with one that is properly sized. 

Plunger or diaphragm pumps do not handle large flow rates in excess of 100 m /hr (4400 US gpm), but they are suitable for a wide range of applications at higher volumetric concentrations than centrifugal pumps. Positive displacement pumps can pump slurries with a weight concentration of 70%. 

Direct current motors are used for continuous operation at constant load when fine speed adjustment and high starting torque are needed. A wide range of speed control is possible. They have some process applications with centrifugal and plunger pumps, conveyors, hoists, etc. 

Because magnetic bearings do not require lubrication, they are particularly suited to applications such as canned pumps, vacuum pumps, turbo-expanders, and some centrifuges. As of 1994, some centrifugal compressors in the 5000-kW power range had been equipped with magnetic bearings. 

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