Centrifugal pumps costs

Process pump modular cost. Figure 8.8 reveals centrifugal pump cost, including both pump and electric motor driver. This cost figure is for 2001. These are general-purpose process pumps of API standard speci-... 

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. 

Centrifugal pumps are widely used in the process industry because of simplicity of design, low initial cost, low maintenance, and fle.xibility of application. Centrifugal pumps have been built to move as little as a few... 

As liquids are essentially incompressible, less energy is stored in a compressed liquid than a gas. However, it is worth considering power recovery from high-pressure liquid streams (> 15 bar) as the equipment required is relatively simple and inexpensive. Centrifugal pumps are used as expanders and are often coupled directly to pumps. The design, operation and cost of energy recovery from high-pressure liquid streams is discussed by Jenett (1968), Chada (1984) and Buse (1985). 

Example 13.4 A centrifugal pump is required to deliver 100 m3 of water per hour with an increase in pressure of 5 bar. If the driver for the pump is to be an electric motor with an efficiency of 90%, electricity costs 0.06 KW h-1, operating for 8300 hours per year, estimate the annual cost of power. 

A centrifugal pump is to be used to produce a 150-psi head at a flow rate of 80 GPM. The maximum pressure in the system will be 200 psi and the maximum temperature is 220°F. A corrosive fluid is being pumped, and it must be determined whether a stainless-steel or cast-iron pump is to be used. The cast-iron pump will last 3 years while the stainless-steel pump will last 7 years. Assume that in 1968 it cost 250 in labor costs to replace a pump. Assume overhead costs involved with obtaining a pump come to 15% of its cost. Assume money is worth 12%. (For other costs see Appendix B)... 

Centrifugal potting, 16 18 Centrifugal pumps, 19 513 affinity laws related to, 21 63 costs associated with, 21 87 efficiency of, 21 60 nonmetallic, 21 76 suction specific speed of, 21 63 Centrifugal sedimentation, 18 142, 143-144 Centrifugal separation(s), 5 505-551 ... 

The process engineer s job is to size both the centrifugal pump and the control valve. The bigger the control valve, the less pressure drop it will take. This means a lower-head pump can be used and energy costs will be tower... 

Figure 7.8. Topical capacity-head ranges of some centrifugal pumps, their 1978 costs and power requirements. Suction and discharge are in inches (Evans, 1979, Vol. 1).

L.B. Evans, A. Mulet, A.B. C orripio, and K.S. Chretien, Costs of pressure vessels, storage tanks, centrifugal pumps, motors, distillation and absorption towers, in Ref. 2, pp. 140-146, 177—183. 

The base cost for this centrifugal pump is estimated using a graph of pump costs versus head and capacity in Ref. P2 (p.6.7). A base cost... 

Thus, the similarity laws enable us to make experiments with a convenient fluid—such as water, for example—and then apply the results to a fluid which is less convenient to work with, such as air, gas, steam, or oil. Also, in both hydraulics and aeronautics valuable results can be obtained at a minimum cost by tests made with small-scale models of the full-size apparatus. The laws of similitude make it possible to determine the performance of the full-size prototype, from tests made with the model. It is not necessary that the same fluid be used for the model and its prototype. Neither is the model necessarily smaller than its prototype. Thus, the flow in a carburetor might be studied in a very large model. And the flow of water at the entrance to a small centrifugal-pump runner might be investigated by the flow of air at the entrance to a large model of the runner. 

Submersible centrifugal pumps are now available with integral packers that allow the screened interval of the well to be isolated from the stagnant column above, thus negating purging requirements and reducing sampling times and costs. 

A similar evaluation relevant to the comparison of efficiency and resulting energy costs with high speed centrifugal pumps, gives a clear indication in favour of the PDP. In a particular case of application, based on an energy price level of 0.12 DM/KWh, the break even point has been reached already after one and a half years. 

Figure 14-37 gives values that are suitable for design estimates of centrifugal-pump efficiencies. Because pump and driver efficiencies must both be considered when total power costs are determined, necessary design data on the efficiency of electric motors are presented in Fig. 14-38. 

Cost of centrifugal pumps. Price includes motor. 

Mechanical seals have fully established themselves for all types of centrifugal pumps in a variety of services. Though more costly than packing, the mechanical seal reduces pump maintenance costs. 

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