Pumps centrifugal Turbine

The majority of centrifugal pumps have performance curves with the aforementioned profiles. Of course, special design pumps have curves with variations. Eor example, positive displacement pumps, multi-stage pumps, regenerative turbine type pumps, and pumps with a high specific speed (Ns) fall outside the norm. But you ll find that the standard pump curve profiles are applicable to about 95% of all pumps in the majority of industrial plants. The important thing is to become familiar with pump curves and know how to interpret the information. 

Kreisel-pumpe, /. centrifugal pump rotary pump, -rad, n. turbine turbine rotor, turbine impeller, -verdichter, m. turbocompres-sor. 

One of several different types of pump including turbine and centrifugal pumps used to convey FW to the boiler inlet at the correct pressure. 

Figure 17.4 shows a centrifugal pump, driven by a steam turbine. The correct operating speed for the pump and turbine is that speed that puts the process-control valve in a mostly open, but still controllable, position. As we slow the turbine to force open the process-control valve, the turbine s governor valve will close. Steam flow to the turbine will decline in accordance with fan laws ... 

All types of equipment, exposed to fluids in motion, are subject to the erosion-corrosion phenomena. This can include pipeline networks (particularly curves, elbows and T-squares), floodgates, pumps, centrifugal fans, helixes, wheels of turbine, tubes of intersections of heat exchangers and measuring devices. In many cases, failures due to erosion-corrosion occur in a relatively short time.16 Most metals are susceptible to erosion-corrosion in the liquid phase under specific conditions. Resistance of metals depends on the physical and chemical properties of the corrosion product and/or the... 

A number of rotating components are in common use in process plants, e.g. turbines, compressors, pumps, centrifuges and stirring paddles, and it is important to understand how such pieces of equipment are affected by the conservation of energy. For a rotating component, the principle of conservation of energy states that... 

White authored numerous papers and was an authority on hydraulic turbines. Around 1900 he was also interested in the Pitot tube for point-wise velocity measurement, as used in flow elements such as pumps or turbines. Given that these tubes are particularly sensitive to the approach flow direction, they are hardly used currently for such tests. In ASME he served on the Power Test Codes Committee for centrifugal and rotary pumps, and was also involved in the Committee on Hydraulic Prime Movers. 

Duchham C. D. and Y. K. A. Aboutaleb. 1976. Some tests in a single stage seml pen impeller centrifugal pump handling coal dust slurries. In Proceedings Pumps and Turbine Conferences, Vol 1. 

Kinetic. Kinetic pumps, which act by impelling a fluid from one location to another, can be centrifugal, regenerative turbine, or special effect (see Fig. 1). 

The primaiy advantages of a centrifugal pump are simplicity, low first cost, uniform (nonpulsating) flow, smaU floor space, low maintenance expense, quiet operation, and adaptability for use with a motor or a turbine drive. 

An example of a typical turboexpander is shown in Fig. 29-46. Radial-flow turbines are normally single-stage and have combination impulse-reaction blades, and the rotor resembles a centrifugal-pump impeller. The gas is jetted tangentially into the outer periphery of the rotor and flows radially inward to the eye, from which the gas is jetted backward by the angle of the rotor blades so that it leaves the rotor without spin and flows axially away. 

Development The following discussion relates specifically to the use of what could be called radial-inflow, centrifugal-pump power-recovery turbines. It does not apply to the type of unit nurtured by the hydroelecti ic industry for the 1 ge-horsepower, large-flow, low- to medium-pressure differential area of hydraulic water turbines of the Felton or Francis runner type. There seems to have been little direct transfer of design concepts between these two fields the major manufacturers in the hydroelectric field have thus far made no effort to sell to the process industries, and the physical arrangement of their units, developed from the requirements of the hydroelectric field, is not suitable to most process-plant applications. 

Tests conducted to operate centrifugal pumps as hydrauhc turbines throughout the head-capacity-speed range show that a good centrifugal pump generally makes an efficient hydraulic turbine. From theoretical considerations it is possible to state that at the same speed... 

FIG. 29-52 Generalized curves showing hydraulic behavior of centrifugal pumps operating as power-recovery turbines. 

Centrifugal blowers or turbines usually cannot generate enough pressure difference to overcome the added resistance of the recycle pipes. In addition, some components may condense out in the cooler, especially with high-boiling materials or at high pressures. These must be recycled by a liquid pump through an evaporator. This in turn makes them approach a steady-state slowly. ... 

The active magnetic bearing s versatility allows it to be used in almost any rotating machine. Examples include compressors, blowers, pumps, turbines, centrifuges, x-ray tubes, vacuum pumps, spindles for... 

The fuel. skid. This could contain a gas compressor if the fuel gas pressure is low and a knockout drum for any liquid contamination that the gas may have. The requirement of fuel gas pressure is that it should be operated at a minimum of 50-70 psi (3.5-4.83 Bar) above the compressor discharge pressure. The compressor and its motor drive fall under the drive level hierarchy. In the case of liquid fuels, the skid may also contain a fuel treatment plant, which would have centrifuges, electrostatic precipitators, fuel additive pumps, and other equipment. These could be directly controlled by the D-CS system, which would then report its readiness to the gas turbine controller. 

Milk-of-lime transfer pumps should be of the open impeller centrifugal type. Pumps having an iron body and impeller with bronze trim are suitable for this purpose. Rubber-lined pumps with rubber-covered impellers are also frequently used. Makeup tanks are usually provided ahead of centrifugal pumps to ensure a flooded suction at all times. Plating out of lime is minimized by the use of soft water in the makeup tank and slurry recirculation. Turbine pumps and eductors should be avoided in transferring milk of lime because of scaling problems. 

The turbine is a special type of centrifugal pump (Figure 3-14) and has limited special purpose applications. 

Figure 3-8. Refinery oil and boiler feed high pressure centrifugal pump. Courtesy Delaval Steam Turbine Co., currently Transamerica Delaval, Inc.)...

Figure 3-33. Performance of turbine type centrifugal pump. (Courtesy Roy E. Roth Co.)...

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