Life cycle costing application

Explosion-welded constmction has equivalent or better properties than the more compHcated riveted systems. Peripheral benefits include weight savings and perfect electrical grounding. In addition to lower initial installation costs, the welded system requires tittle or no maintenance and, therefore minimizes life-cycle costs. Applications of stmctural transition joints include aluminum superstmctures that are welded to decks of naval vessels and commercial ships as illustrated in Figure 11. 

When a single technique is employed only local life-cycle cost minimization is achieved. If the global life-cycle cost is to be minimized, a number of techniques have to be applied (Watson et al., 1996). In this case, tools and techniques shouldn t compete with each other, but be complementary in the product development process. The correct positioning of the various off-line tools and techniques in the product development process, therefore, becomes an important consideration in their effective usage. Patterns of application have been proposed by a number of workers over several years (Brown et al., 1989 Jakobsen, 1993 Norell, 1993) and the importance of concurrency has been highlighted as a critical factor in their use (Poolton and Barclay, 1996). 

Life cycle cost calculations are an application of investment calculations that have been used in planning and design in industry for several decades. ... 

Capital investments can also be selected on the basis of other measures of performance such as return on investment, internal rate of return, and benefit-cost ratio (or savings-to-investment ratio). Flowever, care must be taken in the application of these methods, as an incremental analysis is required to ensure consistent comparison of mutually exclusive alternatives. Also, rather than requiring a separate value to be calculated for each alternative, as in the case of the life-cycle cost method, these other methods incorporate the difference between two mutually exclusive alternatives within a single measure. For example, the net benefits measure directly pressures the degree to which one alternative is more economically desirable than another. 

The mode of operation of a specific application should be the first consideration. The inherent design of each type of compressor defines the acceptable operating envelope or mode of operation that it can perform with reasonable reliability and life cycle costs. For example, a bullgear-type centrifugal compressor is not suitable for load-following applications but will prove exceptional service in constant-load and volume applications. 

The only compressor that is ideally suited for loadfollowing applications is the reciprocating type. These units have an absolute ability to absorb the variations in pressure and demand without any impact on either reliability or life cycle cost. The major negative of the reciprocating compressor is the pulsing or constant variation in pressure that is produced by the reciprocating compression cycle. Properly sized accumulators and receiver tanks will resolve most of the pulsing. 

Wetted instrument parts and pockets generally in accordance with wetted plant items in applicable area. Transmitter housings generally coated as structural steelwork above or constructed from 304L stainless steel according to availability and life-cycle cost. Cable insulation to be PVC, and carbon steel conduit (coated in accordance with guidance above) to be employed throughout. 

In general, the positive displacement machines - there are rotating and reciprocating features - show their main application range for high-pressure and lower-capacity conditions. The turbo- (centrifugal) machines, however, are best suited for high capacity but lower pressure conditions. The selection should be based on an analysis of the life-cycle costs (or costs of ownership) [1]. 

The application boundary between piston- and radial-turbo-compressors lies approximately at 104 nr/h intake volume flow rate (power > 1 to 5 MW). In individual cases, the most economical solution must be determined based on the life-cycle costs. 

In the selection of the right valve, it is always best to work in conjunction with one of the manufacturer s personnel or a consultant who is familiar with the different types of valve available on the market and who can advise the best solution for the application. Different types of valve are available for a reason. These reasons might sometimes be exclusively based on low cost, but also many times solve a particular application problem. Savings at the expense of safety is not a good idea and ultimately leads to increased LCC (life cycle cost of the valve), loss of valuable product, environmental pollution, damage to installations and, most importandy, potential loss of life. 

MBR technology is probably the membrane process that has had most success and has the best prospects for the future in wastewater treatment. Trends and developments also indicate that this technology is becoming accepted and is rapidly becoming the best available technology (BAT) for many wastewater-treatment applications. The cost of an MBR plant for secondary treatment is still higher than that for a CAS plant, but as the numbers of MBR plants increase, and as membrane costs fall, the life cycle cost differential will soon disappear, and the process advantages should lead to rapid uptake of the MBR system by the... 

The application of waste-management practices in the United States has recently moved toward securing a new pollution prevention ethic. The performance of pollution prevention assessments and their subsequent implementation will encourage increased activity into methods that will further aid in the reduction of hazardous wastes. One of the most important and propitious consequences of the pollution-prevention movement will be the development of life-cycle design and standardized life-cycle cost-accounting procedures. These two consequences are briefly discussed in the two paragraphs that follow. Additional information is provided in a later subsection. 

The hfe of a gas turbine depends on the above detailed operational characteristic. It is interesting to note that, for a gas turbine life of 25 years, the life cycle costs can be distributed as 5—10 percent on initial cost, 10-20 percent on maintenance costs and 70-85 percent on cost of fuel. Gas turbines will be very widely used in the 21st century in combined cycle applications as the power source for the world. These combined cycle plants will have efficiencies in the high fifties and will cost between 1000 and 1200 per kW, using 1994 as a monetary benchmark. 

K. K. Humphreys and D. R. Brown, Life Cycle Cost Comparison of Advanced Storage Batteries and Duel Cellsfor Utility Stand-Alone and Electric Vehicle Application, Pacific Northwest Laboratory, Battelle Memorial Institute, 1990. 

Selection of fluoropolymers is an integral part of the overall material selection process. This implies that all the available materials such metals, ceramics, and plastics are considered candidates for an application. The end user then considers these materials against established criteria such as required life, mean time between inspection (MTBI), ease of fabrication, frequency of inspection, extent of maintenance and, of course, capital cost. More often than not it is the initial capital cost, rather than the life cycle cost of equipment, that affects the decision made during the material selection step. However, the most important piece of data is the corrosion resistance of a material in the medium under consideration over the life of the equipment. This information is available in a different format for plastics than for metals. A comparison is appropriate. 

Catalytic control devices are not necessarily inexpensive. For many applications, the cost of the catalyst itself can represent nearly 50% of the total investment for the control system. In addition, the performance of the catalyst usually degrades over time, gradually losing the ability to convert pollutants into harmless compounds. When the catalyst thus becomes deactivated, it must be regenerated or, more often, replaced with fresh catalyst. Because the catalyst is costly, the costs of catalyst deactivation can become a very significant fraction of the life-cycle costs of the control system. 

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