Capital cost shape

A low temperature of approach for the network reduces utihties but raises heat-transfer area requirements. Research has shown that for most of the pubhshed problems, utility costs are normally more important than annualized capital costs. For this reason, AI is chosen eady in the network design as part of the first tier of the solution. The temperature of approach, AI, for the network is not necessarily the same as the minimum temperature of approach, AT that should be used for individual exchangers. This difference is significant for industrial problems in which multiple shells may be necessary to exchange the heat requited for a given match (5). The economic choice for AT depends on whether the process environment is heater- or refrigeration-dependent and on the shape of the composite curves, ie, whether approximately parallel or severely pinched. In cmde-oil units, the range of AI is usually 10—20°C. By definition, AT A AT. The best relative value of these temperature differences depends on the particular problem under study. 

An extruder can, under suitable conditions and with the right ingredients, mix, cook, knead, shear, shape and form. Claims are made that an extruder saves capital cost since the capital cost of an extruder is less than that of the other equipment needed to perform all these operations. This may be true but is not necessarily the way that an existing bakery would view things since they probably already have the traditional equipment and need to purchase an extruder. 

Injection Molding The most precise control of shape and dimensions, highly automatic process, fast cycle time the widest choice of materials. High capital cost is only good for large numbers of parts large mold pressures (140 MPa). 1,000-10,000... 

Impactor crushers have many advantages over jaw and gyratory crushers — in addition to high reduction ratios, they produce a eubical particle shape, have lower capital costs, require less head-room and are more easily installed. Their... 

As moulds have a high capital cost, injection moulding is usually economic, only if more than 10000 products are made. It is preferable to reduce the cycle time than to invest in a second mould to achieve the required production rate. The mould only has a high productivity if the cooling time, which dominates the cycle time, is minimised. Consequently, the product wall thickness is minimised (Eq. 5.4 predicts the effect on the cooling time). Sections 3 and 4 of Chapter 13 consider further suitable product shapes for injection moulding. 

Containment is the last barrier in the defense in-depth strategy. Therefore, the containment vessel has to cover the components that may leak radioactive materials. In case of an accident, the containment wall has to be strong enough to handle high containment pressure. Ideally, a spherical containment shape is ideal for mechanical challenges. However, this design increases the capital cost of an SMR. Therefore, aU the SMRs except IRIS use cylinder geometry (Table 20.4). 

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