Lubricant Analysis: an essential tool in conditioned maintenance plans
17 May 2022All machines and machinery with mechanical components in contact with relative motion experience wear damage, even when lubrication is adequate. When we talk about breakdowns, we are not talking about "if it will happen”, but "when will it happen”. But how to anticipate breakdowns?
Lubricants, as a rule, contain the necessary clues - important information about the state of condition of the equipment they lubricate, as well as indicators on the evolution of this state if proactive measures are not taken. Thus, for the factory equipment to be productive, or more productive, it is essential to follow the evolution of the wear of the various lubricated organs, and to seek to detect changes in the physical-chemical characteristics that occur in the lubricant.
We call this conditioned monitoring programs by lubricant analysis, a type of conditioned maintenance that includes monitoring the condition of a given equipment over time using different techniques from a sample of the lubricant. The analysis of this sample allows us to perceive when there are changes in the normal wear pattern, anticipating eventual failures and being able to act preventively.
The best program will always be the one that allows you to predict the condition of the equipment, and thus precisely define the maintenance needs. This strategy is referred to as Precision Maintenance. In such a strategy, a lubricant analysis program plays a crucial role and, if well implemented, provides valuable information to optimize maintenance resources and, at the same time, increase equipment and lubricant reliability. This analysis makes it possible, for example, to accurately predict and diagnose the onset of a breakdown, indicating to the maintenance team where and how to act, and even how to avoid and prevent future breakdowns.
The objective is to optimize maintenance and increase equipment reliability
The best program will always be the one that allows you to predict the condition of the equipment, and thus precisely define the maintenance needs. This strategy is referred to as Precision Maintenance. In such a strategy, a lubricant analysis program plays a crucial role and, if well implemented, provides valuable information to optimize maintenance resources and, at the same time, increase equipment and lubricant reliability. This analysis makes it possible, for example, to accurately predict and diagnose the onset of a breakdown, indicating to the maintenance team where and how to act, and even how to avoid and prevent future breakdowns.The benefits of lubricant analysis can be grouped into two groups: one aimed at savings, and another that will be better characterized as gains.
Savings:
- Reduce replacement costs and unnecessary work orders;
- Avoid major repairs and collateral damage;
- Make fewer prediction attempts;
- Extend equipment and lubricant life through proactive actions.
Earnings:
- Ensuring the efficient operation of the equipment;
- Reduction in the duration and frequency of stops and consequent increase in production;
- Elimination of forced stops (with high production costs) and efficient operation for longer.
The success of these programs fundamentally depends on the implementation strategy, which includes sample collection and scientific interpretation of laboratory results in the context of the equipment. Many programs, however, end up not being successful and the results of their implementation fall far short of expectations.
Program success depends on implementation strategy
Often, lubricant analysis is only sought when there is already a suspicion of an equipment problem. This approach is not very effective because, like any other conditional maintenance technique, a trend analysis is privileged, and without the analysis of a reference sample (in normal operation) the diagnosis becomes more difficult.
Equally important is choosing the proper analysis range. An analysis must be made of the balance between the cost of the monitoring plan, the value of the equipment and the repair costs in the event of a catastrophic failure and the losses associated with an unplanned stoppage due to failure. Maintenance intervals that are too long are undesirable, as information on the appearance and evolution of the state of potential points of failure may be lost.
Once the periodicity of extraction of lubricant samples has been established, it is necessary to establish the next key success factor: strategy and procedure for extracting a representative sample of the equipment's lubrication system and minimizing the distortion of the information when extracted (e.g. contamination ).
Once the sample has been extracted, it must be analyzed using specialized laboratory techniques. These techniques will allow an assessment of the state of the oil, contamination (particles external to the lubricated system, water, etc…) and the wear of the mechanical components. Whatever the action to be implemented - proactive (eliminate the cause of the anomaly), or predictive (prevent the anomaly) - it is essential that the techniques provide complete information about the state of condition of the lubricant and equipment. Thus, the choice of analysis techniques to apply to a given sample depends on the type of equipment to be monitored and the operating conditions to which it is subject.
Lubricant analysis supports maintenance in various types of industry
The analysis of the condition of an equipment through the analysis of lubricants depends largely on the interpretation of the results obtained after the analysis of the sample. For this reason, it is essential that the interpretation of the overall results be performed by a lubrication engineer or tribologist specialized in the area of lubricant analysis.
Lubricant analysis answers several questions: Is the wear present severe? Is there contamination? Is the oil degraded?
Our experience of more than 25 years in the analysis of efficiency and wear in tribological contacts allows us to answer these questions which, together with other information, enable the early detection of premature failures and provide informed support for maintenance decisions. In this way, it becomes easier to implement proactive actions and to plan and schedule corrective measures, with all the benefits that come from this.