Pumps/pumping

AUTOMATED INSTRUMENTATION - CLINICAL CHEMISTRY] (Vol3) -pumps [PUMPS] (Vol 20)... 

ASME recommends periodic monitoring of all pumps. Pump vibration level should fall within the prescribed Emits. The reference vibration level is measured during acceptance testing. This level is specified by the manufacturer. 

Cooling tower Threaded pipe joints Bolts, nuts, washers Partially exfoliated coatings Lap joints in sheet metal Between bushings and shafts on pumps Pump gaskets... 

De-watering of coal, tin, copper or gold mines, coal washing and sludge pumping Pumping industrial effluents... 

The graph (Figure 5-2) shows the useful work of a pump. Notice that the pump pumps a combination of head and flow. As a general rule, as flow increa.ses, the head decrea.ses. 

Blockages or faulty pumps. Pumps should be checked periodically as instructed by the manufacturer. They can be calibrated using rotameters or bubble flowmeters. Unless pumps possess a limiting orifice they should be calibrated with the air indicator tube in position. 

The process involved in the incident is concerned with the separation of crude into three phases. The crude is pumped into a two stage separation process where it is divided into three phases oil, gas, and water. The water is cleaned up and dumped to drain. The remaining mixture of oil and gas is then pumped into the main oil line where it is metered and sent on for further processing. A simplified process diagram is shown in Figure 7.1. The case study described here is centered on a flange leak in one of the oil pipeline pumps (pump A) and its associated pressure relief valve piping. 

The separation plant had been running smoothly for several weeks and the planned shutdown was some time away. On the day of the incident a number of unusual events occurred which contributed to its development. Shortly after the start of his day shift, the control room operator received a high vibration alarm from booster pump A in the crude fluid separation building. Following normal procedure, he switched over to the standby pump (pump B), switched off pump A, and told his supervisor of the alarm. The supervisor subsequently organized a work permit for work to be carried out on pump A by the day shift maintenance team. The permit was issued and repair work... 

The report includes pedigree information on each plant. This includes plant name and unit number, type, vendor, number of pumps, pump designer, pump model number, and number of seal stages. 

Figure 3-12. Single-stage, high speed (>5000 ft) centrifugal process pump. Pumps are high speed, gear driven, and especially suited for applications in light hydrocarbon liquid service. (Courtesy Sundstrand Fluid Handling, Inc.)...

The theoretical maximum suction lift at sea level for water (14.7 psi) (2.31 fi/psi) = 34 ft. However, due to flow resistance, this value is never attainable. For safety, 15 feet is considered the practical limit, although some pumps will lift somewhat higher columns of water. WTen sealing a vacuum condition above a pump, or the pump pumps from a vessel, a seal allowance to atmosphere is almost always taken as 34 feet of water. High suction lift causes a reduction in pump capacity, noisy operation due to release of air and vapor bubbles, vibration and erosion, or pitting (cavitation) of the impeller and some parts of the casing. (The extent of the damage depends on the materials of construction.)... 

In general, rotary pumps with discharge pressure of up to 100 psi are considered low-pressure pumps. Rotary pumps with pressure between 100 and 500 psi are considered moderate-pressure pumps. Pumps with pressure beyond 500 psi are considered to be high-pressure pumps. 

Rotary pumps with volume capacities up to 50 gal/min are considered to be small-volume capacity pumps. Pumps with volume capacities from 50 to 500 gal/min are moderate-volume capacity pumps. And pumps with volume capacities beyond 500 gal/min are large-volume capacity pumps. 

Except for its narrow specificity, the ATRI gene product shares a number of properties with the higher eukaryotic MDR proteins responsible for multidrug resistance in tumour cells. The MDR gene products are also transmembrane proteins which seem to function as ATP-dependent drug-efflux pumps pumping out a variety of structurally unrelated compounds (see [25,26]). 

Cost of instrumentation for control of recovery section Cost of electricity for pumps Pump costs (total)... 

A positive displacement pump pumps water at 200 gpm at a pressure of 200 psig. Because a deadheaded pump can be easily damaged, compute the area required to relieve the pump, assuming a backpressure of 20 psig and (a) a 10% overpressure and (b) a 25% overpressure. 

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