Centrifugal pumps vacuum

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... 

Lines in vacuum service, 135—141 Line symbols, 17, 23 Numbering, 23 Lined centrifugal pumps, 171 Liquid-solid particle, separators, 228 Baffle type specifications, 248 Baffle type, 247, 248 Centrifugal, 256, 259-261 Chcvron-vanc, 248, 235 Comparison chart, 230 Cyclone, 259 Specification form, 268 Vane, 259 Wire mesh, 246 York-vane, 248 Low pressure storage... 

Pressure-vacuum relief, 466 Manhours, calculation, 37-40 Material of construction, centrifugal pumps, 211 Pipes, 18, 27, 28... 

Total head, centrifugal pumps, 180, 183 Discharge, 205 Head curve, 198 Suction head, 184, 186 Suction lift, 184, 186 Type, 184 Tubing, 63, 64 Two-phase flow, 124 Calculations, 125-127 Flow patterns, chart, 124 System pressure drop, 125 Types of flow, 124, 125 Utilities check list, process design, 34 Vacuum,... 

A centrifugal pump is to be used to extract water from a condenser in which the vacuum is 640 mm of mercury. At the rated discharge the net positive suction head must be at least 3 m above the cavitation vapour pressure of 710 mm mercury vacuum. If losses in the suction pipe account for a head of 1.5 m. what must be the least height of the liquid level in the condenser above the pump inlet ... 

If the slurry is fed to the filter by a centrifugal pump that delivers (approximately) a constant head, or if the filter is operated by a controlled vacuum, the pressure drop will remain essentially constant during operation and the flow rate will drop as the cake thickness (resistance) increases. In this case, Eq. (13-36) can be integrated for constant pressure to give... 

Often, centrifugal pumps develop seal leaks. If the suction of a centrifugal pump is under a vacuum, air will be drawn into the pump through the leaking seal. The pump s capacity will be severely reduced. To stop the suspected air leak, I sprayed water from a hose over the pump s seal. Now, instead of sucking air, the leaking seal drew in cold water. As a result... 

Pumps are standard bronze centrifugal pumps, except those in vacuum service, which have double rotary seals. 

PPDS works on the principle of metering pumps and employs diaphragm, bellows, centrifugal, or vacuum-pressure-dispense pumps. These systems may be used for slurries including shear-sensitive slurries and cause minimal recirculation during slurry usage and replenishment. 

When the reduction in pressure was carried out in many small steps, as in the case of Fig. 4, Curve B, only a small amount of air was liberated with each step. This allowed enough time for the vacuum pump to remove the liberated air during the periods between the measurements. Therefore, the centrifugal pump produced satisfactory results. 

Drying Moisture Pumping From water wash centrifuge to vacuum dryer to storage tank 82 (180) Ambient to 50 (122) Nitrogen or air... 

From the valve, the filtrate goes to a receiver where liquid and air (or other gas) are separated, the liquid usually being removed by a centrifugal pump on the bottom of the receiver, and the gas by a vacuum pump and/or condenser. 

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. 

To protect operators from solvent fumes while drum emptying, the use of a vacuum receiver is effective. If a centrifugal pump is used, spillage from its suction... 

Potassium ferrocyanide trihydrate [14459-95-1] M 422.4, piq 2.57, pK 4.35 (for ferrocyanide). It is purified by repeated crystallisation from distilled water, and never heating above 60 . The anhydrous salt is prepared by drying at 110 over P2O5 in a vacuum desiccator. To obtain the trihydrate, it is necessary to equilibrate the salt in a desiccator over a saturated aqueous solution of sucrose and NaCl. It can also be precipitated from a saturated solution at 0° by adding an equal volume of cold 95% EtOH, setting aside for several hours, then centrifuge and wash with cold 95% EtOH. It is finally sucked air dry with water-pump vacuum. The anhydrous salt is obtained by drying the hydrate in a platinum boat at 90° in a slow stream of N2 [Loftfield Swift Chem Soc 60 3083 7958]. 

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