Trinath Sahoo

Root Cause Failure Analysis


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The decision tree and specific steps required to resolve these problems vary depending on the type of problem and its forcing functions or causes.

      Safety

      Any event that has a potential for causing personal injury should be investigated immediately. While events in this classification may not warrant a full RCFA, they must be resolved as quickly as possible. Isolating the root cause of injury‐causing accidents or events generally is more difficult than for equipment failures and requires a different problem‐solving approach. The primary reason for this increased difficulty is that the cause often is subjective.

      1 Failures simply won’t go away by fixing them all the time. We can only eliminate failures if we try to analyze them through Root Cause Failure Analysis. Then, only maintenance department can focus more on improving their asset performance.

      2 To arrive at the correct solution to our equipment problemsRCFA is not about addressing all the probable causes but rather failures being looked back in reverse to determine what really cause the problem. In performing RCFA, each hypothesis is verified until we have gathered enough evidence that these are the actual facts that lead to the failure itself. In completely eliminating the problem, it is important to address not only the physical cause but both the human and the latent cause.

      3 Equipment failures might induce the possibility of secondary damage. Parts that are in the process of failing such as bearings will increase the vibration of equipment, this increase in vibration would be harmful to other parts that are directly coupled to the part that induce the vibration. Oftentimes secondary damage will be more costly than the parts that initially failed

      4 Being proactive will give me a sense of security. Many maintenance personnel believes that a good backlog of maintenance work will ensure them of their job security. This is not the right mindset. Traditional maintenance people is confined to repairs and fixing failures but the scope of our job is beyond boundaries, our real job is to improve our equipment reliability and the scope of maintenance is beyond boundaries CBM, Oil Analysis, Lubrication, Tribology, Coaching their Operators on Basic Equipment Condition, Oil Contamination Control, Spare Parts Management, Maintenance Cost Reduction Team, just to name a few.

      5 We all learn from the failure itself.

      For every failure that occurred and that had been thoroughly analyzed through RCFA, there is a learning that we can all can gained from these experience in order to prevent the recurrence of the failure itself. Sometimes failures speak to us in a different language.

      Root Cause Analysis in a Larger Context

      The roots of RCA method can be traced to the broader field of total quality management or TQM. TQM has developed in different directions more or less simultaneously. One of these directions is the development of a number of problem analysis, problem‐solving, and improvement tools. Today, TQM possesses a large toolbox of such techniques. Further, problem‐solving is an integral part of continuous improvement. Thus, root cause analysis is one of the core building blocks in an organization’s continuous improvement efforts. However, it is important to keep in mind that root cause analysis must be made part of a larger problem‐solving effort that embraces a relentless pursuit of improvement at every level and in every department or business process of the organization.

      The key to a good root cause analysis is truly understanding it. Root cause analysis (RCA) is an analysis process that helps you and your team find the root cause of an issue. RCA can be used to investigate and correct the root causes of repetitive incidents, major accidents, human errors, quality problems, equipment failures, production issues, manufacturing mistakes, and can even be used proactively to identify potential issues.

      The key to successful root cause analysis is understanding a process or sequence that works. The effect is the event – what occurred. A cause is defined as a set of circumstances or conditions that allows or facilitates the existence of a condition an event. Therefore, the best strategy would be to determine why the event happened. Simply put, eliminating the cause or causes will eliminate the effect.

      Root cause analysis is a logical sequence of steps that leads the investigator through the process of isolating the facts or the contributing factor surrounding an event or failure. Once the problem has been fully defined, the analysis systematically determines the best course of action that will resolve the event and assure that it is not repeated. A contributing factor is a condition that influences the effect by increasing the probability of occurrence, hastening the effect, and increasing the seriousness of the consequences. But a contributing factor will not cause the event. For example, a lack of routine inspections prevents an operator from seeing a hydraulic line leak, which, undetected, led to a more serious failure in the hydraulic system. Lack of inspection didn’t cause the effect, but it certainly accelerated the impact.

      There is a distinction between failure analysis, root cause failure analysis and root cause analisis.

      Failure Analysis: Stopping an analysis at the Physical Root Causes. This is typically where most people stop, what they call their “Failure Analysis”. The Physical Root is at a tangible level, usually a component level. We find that it has failed and we simply replace it. I call it a “parts changer” level because we did not learn HOW the “part failed.”

      Root Cause Failure Analysis: Indicates conducting a comprehensive analysis down to all of the root causes (physical, human and latent), but connotes analysis on mechanical items only. I have found that the word “Failure” has a mechanical connotation to most people. Root Cause Analysis is applicable to much more than just mechanical situations. It is an attempt on our part to change the prevailing paradigm about Root Cause and its applicability.

      RCA can be done reactively (after the failure – RCFA) or proactively (RCA). Many organizations miss opportunities to further understand when and why things go well. Was it the project team involved? The change management methodology applied during implementation? The vendor used or the equipment selected? I would argue that performing RCA on successes is just as, if not more, important for overall success than performing RCFAs on failures

      The objectives for conducting a RCA are to analyze problems or events to identify:

       What