Centrifugal pumps hydraulics

Lantern rings for pumps, bellow-type seals for centrifugal pumps hydraulic, pneumatic, earthmoving equipment cylinder valves for O2, CO2, refined gases, chlorine, ammonia... 

FIGURE 6.32 Correction factors for viscous liquids handled by centrifugal pumps. (.Hydraulic Institute.)... 

Hydraulic Institute Standardsfor Centrifugal, Rotay Reciprocating Pumps, Hydraulic Institute, Parsippany, N. J., 1994. 

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. 

Figure 3-46. NPSH reductions for pumps handling hydrocarbon liquids and high temperature water. Note do not use for other fluids.) permission, Hydraulic Institute Standards for Centrifugal, Rotary, and Reciprocating Pumps, Hydraulic Institute, 13th ed., 1975.)...

Figure 5-5W. Jet-flow mixer. TWin flow jets from submerged centrifugal pump allow for a maximum hydraulic shear per unit of power input, high velocities useful for thick slurries. By permission. Penny, W. a, Chem. Eng., Mar. 22,1971, p. 97 [31].

Figure 3-65. Upper limits of specific speeds of single-stage, single and double-suction centrifugal pumps handling clear water at 85°F at sea level (courtesy Hydraulic Institute).

The hydraulic horsepower produced by mud pumps depends mainly on the geometric and mechanical arrangement of the suction piping. If suction-charging centrifugal pumps (e.g., auxiliary pumps that help move the mud to the mud pump) are not used, the pump cylinders have to be filled by the hydrostatic head. 

More pumps fail as a direct result of improper installation than any other single factor. The predominant reasons for these failures include starvation, caused by inadequate or inconsistent suction conditions distortion, caused by pipe strain or improper foundation and turbulent that results from piping or entrained gas problems. Centrifugal pump installation must follow Hydraulic Institute Standards, which provide specific guidelines to prevent these installation and performance problems. This chapter will address the fundamental requirements for proper installation. 

Centrifugal pumps are highly susceptible to turbulent flow. The Hydraulic Institute provides guidelines for piping configurations that are specifically designed to ensure laminar flow of the liquid as it enters the pump. As a rule, the suction pipe should provide a straight, unrestricted run that is six times the inlet diameter of the pump. 

Very few pump installations follow Hydraulic Institute recommendations. A minority of installations fail to follow reasonable engineering practices or even common sense. Therefore, it should not be a surprise that centrifugal pump applications often exhibit chronic reliability and maintenance problems. 

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. 

Hydraulic or flow instability is common in centrifugal pumps. In addition to the restrictions of the suction and... 

In a vibration analysis, hydraulic instability is displayed at the vane-pass frequency of the pump s impeller. Vane-pass frequency is equal to the number of vanes in the impeller multiplied by the actual running speed of the shaft. Therefore, a narrowband window should be established to monitor the vane-pass frequency of all centrifugal pumps. 

Brake horsepower, centrifugal pumps, 200 Driver horsepower, 201 Burst pressure, 405, 456 Cartridge filters, 274-278 Capture mechanism, 279 Edge filler, 278 Filter media, table, 278 Micron ratings, 277 Reusable elements, 281 Sintered metal, 280 Types, 276, 277, 279 Wound vs. pleated, 276, 277 Centrifugal pumps, operating characteristics, 177-180 Calculations, see hydraulic performance Capacity, 180... 

Overall coefficients, 332 Vertical plate coil, 331 Hindered settling velocities, 231, 236 Horsepower, centrifugal pump driver, 201 Hydraulic performance, calculations, 180-188... 

Buse, F. (1981) Chem. Eng., NY 88 (Jan 26th) 113. Using centrifugal pumps as hydraulic turbines. 

This standard covers the minimum requirements for centrifugal pumps, including pumps rurming in reverse as hydraulic power recovery mrbines, for use in petroleum, heavy-duty chemical, and gas industry services. 

Pumps that handle liquids more viscous than water shall have their water performance corrected in accordance with the Centrifugal Pump Section of the Hydraulic Institute Standards. 

The codes, standards, and specifications of the Hydraulic Institute (Centrifugal Pump Section) also form part of this standard. 

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