Implementation of condition based maintenance in manufacturing industry
- 3. In order to reduce operation cost, maintenance cost at once, increasing performance and reliability of production equipment, many of companies have implemented CBM This paper presents the process of implementation and the elements included in the process The main elements in the implementation process are selection of components to be monitored, techniques and technologies as well as installation of technologies and finally how to analyze the results from condition monitoring The results are recorded, this information is leading to useful and reliable knowledge for maintenance work to be cost effective and be able to increase the Overall Equipment Availability (OEA) 11/20/2016 3
- 4. Implementation method is mainly divided into four phases 11/20/2016 4
- 5. Feasibility test, Selection of appropriate techniques to detect failures Selection of technologies Data analysis Evaluation Improvement 11/20/2016 5
- 6. In order to implement CBM, the company should consider different aspects in the early phase of the implementation to estimate the feasibility of implementing CBM. These aspects are classified in organizational, economical and technical aspects. In organizational aspect if CBM is feasible and for instant what type of technologies are appropriate to use A SWOT analysis and maintenance audits of the company’s maintenance activities can also bring useful information to investigate whether using CBM is a proper decision It should be assessed if CBM can improve the work environment 11/20/2016 6
- 7. Economical aspect • In early stage the financial issue cannot be calculated with a high validity • A list of requirements can be estimated to evaluate whether implementation of CBM will be cost effective • The cost of maintenance and production loss per breakdown should also be estimated • This will make a pre-estimation of implementation cost as well as the paybacks that implementation of CBM can have 11/20/2016 7
- 8. Technical aspect • A criticality analysis and maintenance audit can be very helpful to assess the technical feasibility of implementing CBM • By using proper tools or techniques we can detect the failure of the component • By predicting the failure it is possible to prevent the major damage of the component • Plan for maintenance in a time that does not affect production, in order to reduce maintenance cost and production loss 11/20/2016 8
- 9. In order to select the techniques several factors should be considered including; availability of the technology to monitor the parameters, the competence and manpower required to use the technology and the cost effectiveness of applying the techniques. The condition monitoring techniques can be performed in different levels of technology Condition monitoring can be performed either humans, monitoring by their senses, or by using measuring systems 11/20/2016 9
- 10. The measuring systems can be applied either online or off- line. The online measuring systems can provide continuous monitoring of the assets different technologies require different knowledge within organization Higher effectiveness of the technologies with lower cost would be the best choice in selecting the technologies Bearing Condition Monitoring can be described by two techniques o Shock Pulse Method o Vibration analysis 11/20/2016 10
- 11. The level of performing the data analysis depends on the type of technologies that is used The data can be analyzed in a simple way by looking at the graphs which are provided by computer software and analyze the trends Data analysis can be performed in more specifically frequency analysis in a more advanced level which can provide more accurate and reliable data from bearing conditions 11/20/2016 11
- 12. An important phase of implementation process is to evaluate if the implementation has been performed in an appropriate way and if it can provide the desired outputs Some factors can be considered in this regard, such as the type of sensors, positioning of the sensors, cost and the time between detection of a failure and fault The implementation should start with an estimation of cost, after implementation there is a clearer picture of cost, especially for the cost of condition monitoring tools 11/20/2016 12
- 13. it can be observed whether implementation has been performed in a cost effective way An important success factor for the implementation is to find out the most precise interval time between detecting a failure and fault the best instance for the manufacturing company is to have sufficient time after detecting a failure to plan for a maintenance activity in a correct time 11/20/2016 13
- 14. The results from evaluation phase are used for improvement of the implementation Some technical examples of the improvement can be to change the type of sensors, positioning of the sensors and number of sensors the organization should follow up the activities, increase the competence to analyze the data and use CBM effectively, but management support will still be required company should establish a routine monitoring 11/20/2016 14
- 15. It should be clear to what to measure and when to measure. More accurate warning limits will be set by measurement after measurement The techniques should also be used to detect the most failure modes and the most critical assets should be covered by these techniques 11/20/2016 15
- 16. Gas circulation fans electric motor • A gas circulation fan is mounted on top of 920oC pre- heating furnace • It is running 24*7 to keep the gas atmosphere of cracked Methanol and Nitrogen smooth and steady • The fan has a heavy impeller which is assembled to a 4 KW standard electric motor with a long shaft which is rotating at 945 rpm • The bearing in the electric motor is exposed to a high load due to the extra -long motor shaft and a relatively big impeller • the unbalances can cause a failure in the electric motor’s bearing • Due to the working conditions of 920°C in the furnace the motor shaft and the impeller are exposed to a high wear due to material fatigue/metal dusting (erosion of material) which causes unbalance, and in the long run vibration 11/20/2016 16
- 17. • An unbalance in a fan and electric motor, or a fault in a bearing produces extra vibrations and noises • These parameters can be the failure indicators for the fans electric motors which are measurable by vibration analysis and SPM techniques • In this study, online condition monitoring has been selected to continuously monitor the vibrations and shock pulses from the fans and trigger a warning alarm whenever something wrong is detected 11/20/2016 17
- 18. Two shock pulse transducers and one vibration transducer have been installed on the electric motors The transducers are connecting to a system unit by cables. Depending on the type of the unit, it can have several channels for vibration and shock pulse 11/20/2016 18
- 19. 11/20/2016 19 By installing computer software provided by a condition monitoring supplier, the data are being analyzed autonomously The computer software is also able to trigger warning. Hence, the early measurement from the objects can be used as the baseline data and setting warning limits according to the standards
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- 21. According to the observed breakdowns on the fans, one of the main inquiries to be discussed is the reason of the late warnings before breakdowns by having the late warnings, the company is not able to schedule the maintenance work outside of production time to reduce production losses Therefore, some factors have been reconsidered such as the type of sensors, positioning and placing the sensors The result of failure analysis has shown that the lubricant in the bearing has been quite dried 11/20/2016 21
- 22. Thus, a possible reason for the failure is the heat from the furnace which dries the lubricant in the bearing it has been suggested to use an appropriate lubricant than can sustain in high temperatures. Using the sprays on the bearing that protect the lubricant in front of the heat can also be worthwhile 11/20/2016 22
- 23. The process of an implementation of CBM is proposed in order to consider different aspects in the decision making phase and implementation phase of CBM The implementation process can also be a good guide when implementing CBM in manufacturing companies without existing experience in CBM As long as applying CBM is costly, having an appropriate approach for implementation can help to succeed and gain paybacks from CBM analyze the data and follow up the activities is important to have a continuous improvement 11/20/2016 23
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