Cost sheet variable costs

The items may also be classified differently in cost sheets and cost standards prepared to monitor the performance of the operating plant. For this purpose the fixed-cost items should be those over which the plant supervision has no control, and the variable items those for which they can be held accountable. 

The simplest economic model for the guidance of the catalyst chemist is the standard cost sheet. This lists the variable costs (raw materials), fixed costs (capital charges) and semi-variable costs (conversion expense). Typically, these three elements may represent similar proportions of the overall cost per ton of product, but the circumstances following successful catalyst research can vary widely. 

Variable costs 1. Raw materials 2. Miscellaneous materials 3. Utilities 4. Shipping and packaging Typical values from flow-sheets 10 per cent of item (5) from flow-sheet usually negligible... 

When left-clicking within the Other Variable Costs section, the General Expenses dialog box appears, which permits the specification of percentages of product sales charged for selling/transfer expenses, direct research, allocated research, administrative expenses, and management incentives compensation. The defaults shown are those in the cost sheet of Table 17.1 and discussed in Section 17.2. 

The first step in setting up the Solver model is to enter the cost, demand, and capacity information as shown in Figure 5-9 (see sheet Figure 5-12 in spreadsheet Figures 5-9 to 12). The fixed costs X for the five plants are entered in cells H4 to H8. The capacities Kj of the five plants are entered in cells 14 to 18. The variable costs from each plant to each demand city, Cy, are entered in cells B4 to G8. The demands Dj of the six markets are entered in cells B9 to G9. Next, corresponding to decision variables Xy andy cells B14 to G18 and H14 to H18, respectively, are assigned as shown in Figure 5-9. Initially, all variables are set to be 0. 

The solution to the problem is obtained by solving mass and energy balances to yield the quantity and state (i.e., composition, temperature, pressure) of all the streams and the utility requirements. Additional parameters for the process equipment, sufficient so that stream specifications are met and the cost of the equipment can be estimated, are calculated. The cost of equipment, raw materials, and utilities is estimated and an economic analysis is carried out. Methods of cost estimation and economic analysis are presented later in this text. This entire procedure may be repeated many times to examine modifications of the process flow sheet or to find optimal values of key process variables. Computer software can greatly simplify these repetitive calculations for the engineer. But even without the need for repetition, the software may simplify the calculations and provide detail and accuracy that would have been impossible otherwise. 

Conveying-screen dryers are fabricated with conveyor widths from 0.3- to 4.4-m sections 1.6 to 2.5 m long. Each section consists of a sheet-metal enclosure, insulated sidewalls and roof, heating coils, a circulating fan, inlet air distributor baffles, a fines catch pan under the conveyor, and a conveyor screen (Fig. 12-51). Table 12-23 gives approximate purchase costs for equipment with type 304 staimess-steel hinged conveyor screens and includes steam-coil heaters, fans, motors, and a variable-speed conveyor drive. Cabinet and auxiliary equipment fabrication is of aluminized steel or stainless-steel materials. Prices do not include temperature controllers, motor starters, preform equipment, or auxiliary feed and discharge conveyors. These may add 75,000 to 160,000 to the dryer purchase cost (2005 costs). 

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