Safety factors equipment sizing, table

Safety factors, 6,7 equipment sizing, table, 7 Safety, plant, 7... 

Generally the moderation in powder area is limited. For each unit, one makes a choice of the criticality control mode (1) mass in process equipment (interlinks and administrative measures) or (2) shape and size in storage areas (hardware). The double contingency principle will be applied. Calculations will be done using fixed conservative values for densities of products, a water reflector, and as acceptance criteria a K-eff. below 0.95 or the safety factors given in Table 4. 

With regard to specific types of equipment, the safety factor practices of some 250 engineers were ascertained by a questionnaire and summarized in Table 1.4 additional figures are given by Peters and Timmerhaus (References, Section 1.1, Part B, pp. 35-37). Relatively inexpensive equipment that can conceivably serve as a bottleneck, such as pumps, always is liberally sized perhaps as much as 50% extra for a reflux pump. In an expanding industry it is a matter of policy to deliberately oversize certain major equipment that cannot be supplemented readily or modified suitably for increased capacity these are safety factors to account for future trends. 

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