Preventive maintenance factor

However, indirectly the Control System can also influence the value of Ki, in that features of the Control System (e.g. condition monitoring) may allow a new maintenance policy, such as reliability-centred maintenance, and thereby reduce the difference between Kq and Ki. To take this into account, we introduce the preventive maintenance factor, y, with Ki = yKo. 

MaintainabiUty is a characteristic of design, installation, and operation, usually expressed as the probabiUty that a system can be restored to specified operable conditions within a specified interval of time when maintenance is performed in accordance with prescribed procedures. The ease of fault detection, isolation, and repair are all influenced by system design and are principal factors contributing to maintainabiUty. Also contributing is the supply of spare parts, the supporting repair organization, and preventative maintenance practices. MaintainabiUty must be designed into the equipment. Some factors to consider foUow. 

Marlatt, G. Alan. 1985a. "Cognitive Factors in the Relapse Process." In Relapse Prevention Maintenance Strategies in the Treatment of Addictive Behaviors, edited by G. Alan Marlatt and Judith R. Gordon. New York Guildford. 

The frequency of operational qualification of a CE instrument depends on factors such as the manufacturer s recommended OQ interval, the required instrument performance, and the instrument s use. Note that preventive maintenance procedures such as lamp replacement may require repeating the qualification of the particular CE function [3]. The following sections describe the tests to perform and their associated limits that are intended to qualify a CE instrument for its general purpose. Troubleshooting tips for instruments that do not perform to the intended specifications are presented in Section 12.4. 

The oil is periodically replaced to perform its intended functions effectively and to sustain reliability of the components and system. This activity is carried out as a part of preventive maintenance as per the manufacturer s recommendation. The oil change frequency is a function of various factors including operating and environmental conditions, and maintenance practices. The cost of lubricating oil represents an important component of the operating cost of a vehicle and is about 60 to 70% of the fuel cost. 

An important influence on production cost has, of course, the so-called on-stream factor, the number of production days per year. It is standard practice to assume that a well designed and operated plant should be capable to reach a minimum of 330 days per year, a value on which economic calculations are usually based. Modern plants often achieve higher on-stream factors. A beneficial effect is also that many plants achieve higher capacity than the original design. Plant outages because of operational problems or temporary shut downs for economic reasons because of unfavorable market situation can lower the profitability considerable. The on-stream factor is an average value, because plants should shut down only every 2 to 3 years for a major turn-around for repair and preventive maintenance. Only a very few short unscheduled shut-downs for repair work should occur between two turn-arounds. A start up needs between 15 to 30 hours and consumes a considerable amount of natural gas without an equivalent production (100 000-200 000 DM/d). 

The maintenance of facilities includes preventive maintenance programs that identify required preventive maintenance activities and recommended intervals based on safety, reliability, and economic considerations. Factors such as failure rate, replacement costs, impact on operations and safety, lessons learned, and analysis of incident causes are considered. Computerized programs provide for preventive maintenance schedules to be planned, implemented, and monitored. 

Future versions of this application will also consider dynamic risk factors such as user error, mean-time-between failure (MTBF), device failure within 30 days of a preventive maintenance or repair, and the number of years beyond the American Hospital Association s recommended useful life. 

An important factor that should be taken into account while drying PVC is the corrosion of the equipment due to the monomer chloride. Monomer chloride, which is always present in the wet cake, induces pitting corrosion and stress corrosion cracking in parts where the powdery materials are processed. Those parts, therefore, are made of AISI-316L and are partially coated with an acid-resistant coating. It is indispensable to make periodic inspection of the corrosion condition and to make timely replacement of the necessary spare parts. Preventive maintenance is imperative to successful operation. 

Most of the eight table- and stage-setting factors in the Bhopal case, discussed above, relate to one or more of these subsystems of the MIC plant s or the broader society s cultural system. Thus, the lack of an idea of preventive maintenance pertains to the Indian ideational subsystem (of both the plant and Indian society) the lack of effective social institutions of zoning and industrial... 

Some assessors also do a useful life analysis to provide the safety instrumentation engineer with knowledge of any wear out mechanisms and the time periods imtil wear out. Preventative maintenance programs can be established to replace instruments at the end of their useful life knowing this information. Some FMEDA analyses are also extended to evaluate the effectiveness of proposed proof test methods. This provides the safety instrument engineer with proof test coverage factors used for more realistic PFH/PFD/PFDavg calculations. 

As seen in Section 1, Kijima Nakagawa (1991) proposed a cumulative damage shock model with imperfect periodic maintenance actions. Each action reduces the deterioration level by 100(1 — b)% of total damage, where b 6 [0,1]. The same authors introduced in Kijima Nakagawa (1992) an improvement factor t. The amount of damage after the preventive maintenance becomes bi Yi when it was T) before the maintenance action. Moreover the imperfect maintenance action can impact the failure rate of the system, this method is called the improvement factor method . This concept had been introduced by Malik (1979). Nicolai et al. (2009) consider different imperfect maintenance actions which have a random impact on the deterioration level of the system. A random improvement according to the residual time on a finite horizon is rarely considered, that is why, in this paper, such a random improvement is considered. 

Preventive maintenance Most motor carriers follow some sort of preventive maintenance schedule for their vehicles. Preventive maintenance (PM) schedules can be arranged according to mileage, engine hours, or time. The mileage between services will vary widely depending on type of equipment, how rapidly the equipment accumulates miles, and the manufacturer s suggested maintenance schedule for the vehicle and all major components. The FMCSA leaves it up to the carrier to determine their own maintenance schedule based on the above factors. Here is an example of a typical preventive maintenance schedule in use in the industry ... 

A preventive maintenance program can be developed for any industrial function that has a maintenance component. The same principles used in the truck operator example in this chapter can be used for other mobile equipment, machinery, or process maintenance (see Figure A.3). It matters little the type of maintenance. It is more important that the workers, operators, supervisors, and management realize that the care taken in prevention will pay dividends in cost savings, accident costs, less equipment damage, and better overall working conditions and employee attitudes. Care of your physical assets (physical plant, vehicles, machinery, etc.) is critical to the bottom line. The bonus is that you will reduce one of the factors that can contribute to your occupational injury rate. 

Many lAQ problems can be prevented by making sure that the facility s management staff and operations personnel imderstand the many factors which can create these problems. In addition, they must be well trained in the operations of their equipment and must have budgets and support staff to allow them to remain dihgent in preventive maintenance activities. 

Preventive maintenance provides more operational rehabihty however, it also involves higher inspection and maintenance costs, if the inspection strategy is appHed, or higher repair costs if the exchange strategy is applied. Which maintenance strategy will be applied depends on a number of factors, such as Hfespan, personnel structure etc, and will be determined by company management... 

The degradation mechanisms affecting industrial systems, structures and components (SSCs) can be modeled as discrete-state transport processes (e.g., Baraldi et al., 2013 a and b Moghaddas Zuo, 2011). The stochastic transitions between the states obey known models (e.g., WeibuU distribution, exponential distribution, etc.), whose parameters (e.g., the scale and shape factors for the WeibuU distribution, the failure rate for the exponential distribution, etc.) need to be estimated. Degradation models are used in support to maintenance decision making, for example to optimize the inspection period in a preventive maintenance approach or to estimate the remaining useful life of a SSC in a predictive maintenance approach (Zio Compare, 2013). 

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