Pumps, centrifugal action

Data from an existing collection system were analyzed for failure modes and distribution. The results of Pareto analyses indicate the principal causes of failure. A few values of mean times to maintenance action (MTBM) are given for ethylene plant pumps (85 electric driven centrifugal pumps over a 19-month period), and ethylbenzene-styrene monomer plant equipment from 10 months data 4 gas compressors, 3 screw conveyors, 121 pumps, and 235 other items... 

Positive displacement pumps are self-priming by their normal operating action and are designed to cope with mnning dry. Centrifugal pumps are not inherently selfpriming, and need to be provided with assistance in the form of ejectors, as in Figure 32.56 or dry vacuum pump systems. In these systems, a dry vacuum pump allows air to be drawn out and where an automatic valve prevents... 

Action of a Centrifugal Pump Briefly, the action of a centrifugal pump may be shown by Fig. 10-37. Power from an outside source is applied to shaft A, rotating the impeller B within the stationary casing C. The blades of the impeller in revolving produce a reduction in... 

Table 10-15 classifies different types of centrifugal pump-related problems, their possible causes, and corrective actions that can be taken to solve some of the more common issues. These problems in the table are classified into three major categories for these type of pumps ... 

Pumps are of two main classes centrifugal and the others. These others mostly have positive displacement action in which the discharge rate is largely independent of the pressure against which they work. Centrifugal pumps have rotating elements that impart... 

A few other examples in which models may be used include ships in towing tanks airplanes in wind tunnels hydraulic turbines, centrifugal pumps, dam spillways, and river channels and the study of such phenomena as the action of waves and tides on beaches, soil erosion, and the transportation of sediment. It must be emphasized that the model may not necessarily be different in size from its prototype. In fact, it may be the same device, the variables in the case being the velocity and the physical properties of the fluid. 

Rotary centrifugal pumps with no valve action open impeller, closed impeller, volute pumps, turbine pumps... 

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