Cost of maintenance

A suitable maintenance strategy should be developed for equipment by considering the criticality and failure mode, and then applying a mixture of the forms of maintenance described above. In particular, the long-term cost of maintenance of an item of equipment should be estimated over the whole life of the project and combined with its capital cost to select both the type of equipment and form of maintenance which gives the best full lifecycle cost on a discounted basis), while of course meeting the technical, safety and environmental specifications. 

Miscellaneous Direct Costs Estimates for the cost of maintenance and repairs, operating supplies, royalties, and patents are best based on company records for similar processes. A rough average value for the annual cost of maintenance is 6 percent of the capital cost of the plant. This percentage can vaiy from 2 to 10 percent, depending on the severity of plant operation. Approximately half of the maintenance costs are for materials and half for labor. Royalty and patents costs are in the order of 1 to 5 percent of the sales price of the product. 

The advantages of this type are low headroom and low power requirement. The disadvantages are the high cost of maintenance of the screen and the supporting structure owing to vibration and low capacity compared with inchned high-speed vibrating screens. 

Gas turbines, like other mechanical devices, require inspection, maintenance, and service. Maintenance costs include the combustion system, hot-gas path, and major inspections. (See Chapter 21.) The effect of fuel type on maintenance costs is shown in Table 12-8. A cost factor is shown using natural gas as unity. The cost of maintenance is subject to great variations. Recognizing the great difficulty in establishing expected maintenance costs... 

The desirable operating characteristics of equipment include simplicity, convenience and low cost of maintenance simplicity, convenience and low cost of assembly and disassembly convenience in replacing worn or damaged components ability to control during operation and test before permanent installation continuous operation and steady-state processing of materials without excessive noise, vibration or upset conditions a minimum of personnel for its operation and, finally, safe operation. Low maintenance often... 

Huff [23] found that reciprocating and rotary piston pumps were the most economical mechanical systems for their range of application. Obviously, the economic discussions are dependent on the vacuum expected and the local utility costs, plus the cost of maintenance. 

The cost of maintenance may be greatly influenced by the disruption caused by the access requirements. This involves not only direct costs such as scaffolding but indirect ones such as disruption of a process plant, closure of roads, protection of plant and equipment in the vicinity, etc. 

In this method each year s savings need to take account of the fact that, as the equipment gets older, the cost of maintenance and repairs is likely to increase. The effect of inflation can also be allowed for in assuming the annual cash flows through the life of the equipment. 

As the maintenance and repair record indicates the cost of maintenance for the specific item of plant and equipment, a simple system may be used to provide recognition of the different methods by which the work has been carried out, e.g. 

Specific goals and objectives will vary from plant to plant. However, we will provide an example that will illustrate the process. Before goals and objectives can be developed for your plant, you must determine the existing maintenance costs and other parameters that will establish a reference or baseline dataset. Since most plants do not track the true cost of maintenance, this may be the most difficult part of establishing a predictive maintenance program. 

The principal economic implications of corrosion of a plant are the initial cost of construction, the cost of maintenance and replacement, and the loss of production through unplanned shutdowns. The initial cost of the plant is influenced by material selection, and a choice of material that is more corrosion resistant than is necessary for the safe operation of the plant over its design life is a very expensive error. This cost involves initial outlay of money, and plants have been built which could never be profitable because of the inappropriate materials selection. 

The rate of a chemical reaction is influenced by pressure, temperature, concentration of reactants, kinetic factors such as agitation, and the presence of a catalyst. Since the viability of a plant depends not only on reaction efficiencies but also on the capital cost factor and the cost of maintenance, it may be more economic to alter a process variable in order that a less expensive material of construction can be used. The flexibility which the process designer has in this respect depends on how sensitive the reaction efficiency is to a change in the variable of concern to the materials engineer. 

This item will include the cost of maintenance labour, which can be as high as the operating labour cost, and the materials (including equipment spares) needed for the maintenance of the plant. The annual maintenance costs for chemical plants are high, typically 5 to 15 per cent of the installed capital costs. They should be estimated from a knowledge of the maintenance costs on similar plant. As a first estimate the annual maintenance cost can be taken as 10 per cent of the fixed capital cost the cost can be considered to be divided evenly between labour and materials. 

Maintenance The cost of maintenance depends on whether processing materials are solids on the one hand or gas and liquid on the other. Handling solids tends... 

Maintenance costs are very large in the chemical industry. In some cases the cost of maintenance exceeds the company s profit. The magnitude of maintenance costs is given in Chapter 8. The engineer must design to reduce these costs. 

One way of avoiding estimating the number of maintenance personnel is to base the cost of maintenance on the total sales. In 1972, this cost ranged between 3 and 9% of total sales with the largest chemical companies ranging between 6.1 and 7.4%.50 For the whole chemical industry, maintenance averaged 4.8% of the total fixed assets. 

Maintenance effort High maintenance of equipment acceptable Complexity and cost of maintenance is significant factor... 

For HCS to be fully accepted by academia, several conditions will need to be fulfilled. Current HCS instruments are closed black boxes and their expensive maintenance contracts do not allow any hardware or software modifications for adaptation to the diverse needs of academic research. Academic research is typically more diversified than pharmaceutical industry research and the instruments need to be more customizable than they are now. In addition, the image and data formats need to be accessible and open. In academia data is shared between collaborators and will be analyzed with various, partly custom-made software. Therefore the data needs to be accessible and open. Lastly, the yearly costs of maintenance contracts and licenses are particularly difficult to finance in academic research that relies heavily on grants. Grants typically do not cover licensing costs or if they do, when the grant runs out, new sources of funding must be found. In reality, those costs must generally be covered by institutional funds. 

Trying the other solution of the quadratic equation, when x = 10, then the rent charged is (400 + 20 x 10) = 400 + 200 = 600, and the number of apartments that will be rented is (100 -3x 10)= 100 - 30 = 70 apartments. Multiplying the rent of 600 times 70 you get exactly 42,000. The rent is higher, but fewer apartments will be occupied. That would probably cut down on the cost of maintenance and upkeep, but there are a lot of vacant apartments. Now it s up to the landlord (and his conscience). 

Although firms sometimes do anticipate accidents and try to avoid them, the expenditures for adequate prevention have not been, and are not likely to be, invested without the right incentives. To the extent that the firm knows that the costs of maintenance and the inflexibility of traditional safety approaches are greater than using more reliable, inherently safer approaches, the firm may respond by changing its technology. 

Within a typical world-class industrial commodity chemical company the annual cost of maintenance is 3 to 6 percent of the asset replacement costs. A number of significant maintenance activities require very little interruption of continuously operating chemical plants. Everyday maintenance activities that may be accomplished on a routine basis include repairs to a spare pump or spare compressor after it has been properly isolated and cleared of fluids, and overhaul of a fully spared filter or painting. 

It is important to consider both the capital costs associated with designing, purchasing, and installing a piece of bioseparation equipment and the operating costs of maintenance utilities such as electricity, steam, and compressed air labor and any raw materials. In most cases, there will be a trade-off between capital and operating cost which may favor a particular type of equipment, depending on the desired initial capital investment and the economics of the process. 

The popularly used single-screw and multi-screw types have their differences. Each has its benefits, depending on the plastic being processed and the products to be fabricated. At times their benefits can overlap, so that either type could be used. In this case, the type to be used would depend on cost factors, such as cost to produce a quality product, cost of equipment, life cycle of equipment, and cost of maintenance. 

In this patient population, the risk of relapse, with its resulting consequences of suffering, disability, loss of income, potential need for hospitalization, and suicidal risk, to mention some, greatly outweighs the possible side-effect burden and cost of maintenance treatment. 

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