Asset maintenance

This chapter offers an example of how an integrated framework for risk and MCDA analysis can be used in designing asset maintenance strategies for 12 kV MV air-insulated switch-disconnectors. 

Bertling, L., Allan, R. Eriksson, R. (2005). A reliability-centered asset maintenance method for assessing the impact of maintenance in power distribution systems. IEEE Transactions on Power Systems 20(1) 75 2. 

Wilson, A., 2002. Asset Maintenance Management - A Guide to Developing Strategy Improving Performance. Industrial Press, Inc. New York. 

Select appropriate maintenance strategies to implement for asset maintenance... 

These steps encourage the continuous improvement of cost effectiveness associated with assets maintenance. 

Asset maintenance optimization The case-study of an offshore wind farm... 

The nature and rate of atmospheric corrosive attack are dependent on the composition and properties of the thin-film surface electrolyte. Time of wetness and the type and concentration of gaseous and particulate pollutants in the atmosphere largely affect these in turn. The classification of atmospheric corrosivity is important for specifying suitable materials and corrosion protection measures at the design stage and for asset maintenance management to ensure adequate service life. Two fundamental approaches to classifying atmospheric corrosivity have been followed, as shown in Fig. 2.7. These two approaches to environmental classification can be used in a complementary manner to derive relationships between atmospheric corrosion rates and the dominant atmospheric variables. Ultimately, the value of atmospheric corrosivity classifications is enhanced if they are linked to estimates of actual corrosion rates of different metals or alloys. 

Several steps can be taken to maximize the run time for the reciprocating compressor. Since wear is a function of rubbing speed, the piston speed can be kept to a minimum. Chapter 3 made recommendations for piston speed. Reliability problems due to valves are reputed to account tor 40% of the maintenance cost of the compressor. Valves are the single largest cause for unplanned shutdowns. Basically, valve life can he increased by keeping the speed of the compressor as low as practical. At 360 rpm, the valves are operated six times a second. At 1,200 rpm, ihc valves operate 20 times a second or 1,728,000 times in a day. It is not difficult to understand why the valves are considered critical. To keep the reliability in mind, valve type, material selection and application considerations such as volume ratio, gas corrosiveness, and gas cleanliness need attention by the experts. One final note is that while lubrication is an asset to the rubbing parts, it is not necessarily good for valve reliability. 

Each item of plant and equipment is allocated a specific asset number. This number can be either for a complete boiler (with associated equipment) or a specific asset number for the boiler and individual asset numbers for the associated equipment. It is advisable to restrict this numbering sequence to a minimum while ensuring that it meets the specific needs of the company and location. Care must be exercised in determining the asset numbering during this manual phase if it is envisaged that, on completing a satisfactory trial period, the planned maintenance system will be transferred onto a computer. 

Peaks and troughs in the man-hours allocated weekly for planned maintenance can be avoided if hours entered are added up for each week after a number of assets have been scheduled. Treating each plant room or department in this way provides the number of man-hours required for the respective plant room and/or department. All assets to be covered by the planned maintenance system are scheduled in the same format, thereby providing the engineer responsible for allocating the work tasks with total manhours for each trade group. 

The above planned maintenance manual system provides a firm basis on which a computer-planned maintenance system may be developed. Having such knowledge and experience from working the manual system, the benefits that can be accrued from planned maintenance systems compared to the corrective or other non-planned methods previously used are numerous. It can be found that, due to the large amount of assets to be managed by the administration, it would be beneficial for the planned maintenance system to be transferred onto a computer system. A major non-technical weekly task is one of producing work dockets for issue and the subsequent entry into the maintenance records on completion of the work task. 

What assets, departments, etc. are to be included within the proposed program This plays a major part in the decision to be reached on to what hardware and software is to be purchased. To support a system covering a number of areas and departments it will be necessary to consider network systems. Therefore, the computer maintenance system to be purchased must accommodate such arrangements. 

If, after assessing the various computer and software packages, the decision is made to implement the proposed maintenance system on computer rather than by manual methods caution must be exercised. Irrespective of the above-mentioned benefits, the use of a computer does not increase work output but it does provide the department with a very sound method of improving the management of the company s assets and resources. 

In establishing a sound maintenance program, budget costs for both operation of the department and associated costs of the user department s assets will be readily obtained. 

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. 

Determination of critical assets that might be subject to malevolent acts that could result in undesired consequences What are the malevolent acts that could reasonably cause undesired consequences on these assets electronic, computer, or other automated systems that are utilized by the public water system (e.g., Supervisory Control and Data Acquisition (SCADA)) the use, storage, or handling of various chemicals the operation and maintenance of such systems... 

While less protection may initially reduce the capital investment and the ongoing maintenance costs, the additional risk to company assets, employees, the environment, and the public could be substantial. The potential for escalation increases due to the lack of fire protection systems. Should a company choose less protection, potential adverse affects such as damage to reputation, increased insurance costs, loss of business and customers, as well as possible charges of criminal negligence could become a factor in the event of an incident. 

There are other aspects to the maintenance of a product in the market. The ability to protect and recoup investment is vital if new products and the development of existing products are to be sustained. Intellectual property rights provide various methods of protecting products and can be an important and a valuable asset in providing legitimate barriers against domestic and foreign competition. 

Faced with massive increases in the price of imported gas in combination with ineffective billing and revenue collection during the 90-s the Georgian gas sector incurred heavy domestic and foreign debts. The lack of financial resources required for rehabilitation and maintenance has led to deterioration of a large proportion of the physical assets. 

Return on Net Assets (RONA) h Increase productivity Optimize assets y Reduce inventories /I r Reduction in repair and maintenance costs/conversion costs Optimized production planning / Reduction in off-specification material Optimized raw material and finished goods logistics... 

Capital expenditure is, of course, required to maintain and expand the company s asset base. It should be analyzed with the same close scrutiny as any other cash expense and must yield a return on investment that strengthens the economic value of the asset base. Specifically, capital expenditure for maintenance, removing bottlenecks, and major investments require different analytical approaches. 

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. 

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