Anything known as viscous does not mean it is lubricant. There are so many confusing perceptions among us regarding machine lubricants and its cost analysis. We are losing millions in dollar due mainly to lack of knowledge or proper practice. Lubrication practices within a plant have a direct effect on plant and equipment performance. When a lubricant works effectively in a machine with no chemical degradation and with limited contamination within it, wear will be reduced and equipment performance will be improved. The key to reduction in component wear and increase in equipment performance is effective and clean average lubrication film thickness - in other words, protecting and maintaining a good lubrication viscosity.
The industrial maintenance world today is predominantly focused on plant and equipment performance. The real meaning of equipment performance is often hidden behind other terms like World Class Maintenance, Asset Efficiency, Proactive Maintenance, Predictive Maintenance, Lubrication Management, Lean Manufacturing and even 5S (Sorting, Straightening, Systematic cleaning, Standardising, and Sustaining).
The maintenance team always believes that they have enough tools and systems to cover reliable maintenance. But so many sophisticated system has been developed now ranging from condition analysis to preventive maintenance and corrective maintenance programmes. It is said that millions of dollars are spent to improve machine condition and reliability. Improper lubrication is still cited as the primary cause of premature equipment failure today.
Kenneth Bannister in his book 'Lubrication for Industry' said, "It is generally accepted in the lubrication community that 60 per cent of all mechanical failures are due to inadequate or improper lubrication practices."
As part of analysis, many investigations were conducted as to why bearings fail? It is alarming that over 60 per cent of the damages are lubrication related. The bearing is the rotating core of the machine and if we can reduce the lube-related failures, it will directly improve the equipment reliability and bearing consumption. All rotating components need a good lube film thickness to separate the metal components and reduce wear. Generating a good film thickness is a chemically complex mechanism. When the lubrication works in a reliable way, equipment reliability will improve as a result -- thereby reducing wear and failures in machine.
Lubrication engineering is all about lubrication film! SKF has stated that, "Bearings can have an infinite life when particles larger than the lubricant film are removed." It means that the removal of abrasive particles prevents bearing wear.
In rotating parts, a good average of lubrication film thickness is essential. The metal surfaces are separated with the average thickness of this separation or film being very small. In fact, it is about one-twentieth of the thickness of a strand of human hair. The equivalence can be explained with an example: when a 50-micron particle of hard contaminant goes through the bearing, it is like driving your car over a one-meter diameter boulder. When there are hard contaminants in the oil and they are greater in size than average lube film, then it leads to surface indentation and scratching, which is a process that can lead to bearing or component failure.
Contamination is one of the problems among hundreds and this can be particle contamination or chemical contamination or both. There are five steps we need to consider in managing the oil cleanliness and contamination levels, such as 1) receipt of new oil, 2) storage and conditioning of new oil, 3) dispensing of the oil to the machines, 4) stopping contaminants from entering the machine, 5) removing contaminants generated in the machine from wear.
The oil can also be contaminated chemically -- especially when water enters the system or oxidation occurs within the process. These chemical contaminants will also affect the average lubrication film thickness and any well managed lubrication activity will use an oil analysis process to monitor their development.
A smart structured lubrication plan will require some investments for lube management software, which depends on how advanced a company is with their existing lubrication policy and their size. These costs can be anywhere from $20,000 to $150,000. The followings are three examples of how the investment payback will come from: 1) The elimination of one failed electric motor due to lack of lubrication, 2) The doubling of life of a number of gearboxes due to cleaner oil, and 3) The reduction in bearing spent by a conservative 30 per cent annually. The core concept of a total lubrication management programme is to track all your lubricated assets the following way and keep them operating effectively with high authenticity.
AUDITING: It is the most important part in case of maintaining the records of lubricant application for all assets within the organisation and ensure quality product with quality services.
APPLICATION SCHEDULE: It's better to use the scheduler to create and manage daily/weekly/monthly lubrication routes. Let's keep track of which assets are receiving the correct lubricant on schedule, and pinpoint those assets which are not getting lubricated as per the schedule. It is necessary to set specific people for doing this work.
LOGISTICS: The Parts Manager has the capacity to store lubrication specification information (viscosity, pour point, SAE number etc.). Lubricants can be stored in one unit (barrels, cans, etc.) and distributed in another unit such as ounces or grease shots. The amount of lubrication added to a particular asset or reservoir can be tracked, and alarms raised if lubricant consumption is above a pre-defined level.
CONTAMINATION CONTROL: Any contaminant element is a cancer cell for lube oil as well as machine. One should keep in mind that a silicon particle (sand) is harder than Iron.
LUBRICANT ANALYSIS: Used lube oil analysis can save millions of dollar by increasing Optimised Drain Interval (ODI) and controlling unexpected break down.
A significant amount can be saved by using proper lubrication management such as (source EM). USA: The US invests $23 million to strengthen lubrication management every year while receives $16 billion in savings with the ROI being 696 times. UK: Based on British investigations, the benefit from lubrication management is more than £500 million annually. Canada: Investigations in Canada showed that the friction and wear causes $50 billion loss annually while through the improvement of lubrication management one-third of the loss can be saved. Japan: According to Japan's statistics of equipment failure, more than 36 per cent is caused by poor lubrication. China: China's statistics is about 55 per cent to 60 per cent failure due to pore lubrication. Bangladesh: In Bangladesh, there is no specific data, but it can be said from my lubrication field experience that machine failure rate will be around 57 per cent to 62 per cent due to improper lube management.
The industrial sector in Bangladesh contributes to the GDP's (gross domestic product) 33.71 per cent and grew 11.99 per cent against 10.22 per cent in fiscal 2016-17. All industrial segments are importing state-of-the-art machineries to improve productivity in an efficient way. In most of the cases, it has been found that there are negligence of lubrication management and ignorance of original equipment manufacturers in preparing recommendation although lubrication practices within a plant have a direct effect on plant and equipment reliability. A lubrication reliability strategy is more cost-effective than analysis of cost for lubricants or machine parts.
Engr. Md. Shahin Alom, currently Deputy General Manager at MJL Bangladesh Limited, has more than 11 years of job experience in petroleum downstream segment (Lubricants) in Bangladesh. [email protected]
