A Method Based on RCM Used in the Spot Welding Robot Station Maintenance
|School||Shanghai Jiaotong University|
|Keywords||Welding robot Maintenance management Reliability-Centered Maintenance Failure Mode and Effects Analysis|
With the development of the automotive industry in the domain of lean manufacturing, a good many of the suppliers of automobiles are also turning to lean manufacturing companies. However, the maintenance management in these companies is still falling behind relatively, especially for the management of equipments with systems of automation and integration, such as spot welding robots, whose efficiency can’t be developed adequately. Therefore, the most important task in these companies is to reform the current maintenance management and increase the efficiency of these fixtures, so as to improve the capacity of the competition and the profitability in the market.The objective of this thesis is to analyze the inadequacy of the existing maintenance pattern and rebuild a new one based on Reliability-Centered Maintenance (RCM). Firstly, an autonomous maintenance team is organized. Secondly, the functions and specification of the fixtures are analyzed. Thirdly, the failure modes of function are defined, and a list involved all the failure modes mentioned as above is made by using the method of failure mode and effects analysis (FMEA). Fourthly, the root causes of each failure modes are found and the effects are listed, the top priorities to meet all the failure modes are found by using the judgment of the Risk priority number (RPN). Fifthly, what should be done to prevent all failures is evaluated by the logical decision of RCM, and which kind of measures could be taken is also identified when the appropriate protective measures couldn’t be found. While the logical decision of RCM is used, it is necessary to think about all the possibilities based on security, economy and function, combined with the explicit and potential error modes, there will be six aspects have to be evaluated if it is suitable to use the maintenance methods as below: visual inspection, maintenance, operator’s monitor, function test, time to repair and time to scrap. The assessment is made by the data of regular maintenance, which will be used in tracking the results and evaluating the appropriateness of above maintenance work. Finally, the Overall Equipment Effectiveness (OEE) and Key Performance Indexes (KPIs) are used to measure the performance of maintenance work and improve the cycle.This survey suggests that the overall efficiency of the spot welding robots is mostly improved by using the maintenance method of RCM. It not only promotes the levels of maintenance management, but also makes a better basis to the future’s efficiency advancing and cost reduction. The method based on RCM theory can be a better choice to apply to the maintenance of other kinds of fixtures.