Machinery Lubrication magazine published by Noria Corporation
Issue link: https://www.e-digitaleditions.com/i/1171112
ML estimated that a 10 percent reduction in maintenance is equivalent to a 40 percent increase in sales. From a manpower/overhead perspective, it seems obvious that improving maintainability should be the desired goal. In most ways, cost-eff ectiveness and produc- tivity are tied together. A machine that runs more often should be more profi table in that it is achieving its desired operational purpose and not drawing the attention of the main- tenance team for additional parts or labor. erefore, it makes sense to approach the larger cost-improvement issue from a stand- point of how to reduce equipment downtime by preventing lubrication-related failures. Ernest Rabinowicz, a professor at the Massachusetts Institute of Technology (MIT), published a study showing that 70 percent of machine failures can be attributed to lubrication-related problems, with 50 percent for mechanical wear and 20 percent for corrosion. It's apparent that using the right oils and greases and maintaining them inside the proper operating condi- tions will go a long way toward correcting or preventing most mechanical failures at your job site. Noria generally breaks down the journey to lubrication excellence into six categories: lubricant selection, reception and storage, handling and application, contamination control, lubricant analysis, and environ- mental disposal. is article will focus on the fi rst fi ve categories and provide exam- ples of how to improve in regard to overall lubrication excellence and cost-eff ectiveness. While environmental disposal is critical, it's not necessarily a good place to look for cost savings. Lubricant Selection Selecting the proper lubricant from the beginning is the most important step you can take to improve machine productivity. Your equipment's needs will drive the selection process, but having a thorough understanding of diff erent lubri- cant properties will allow you to pick the optimum solution. ree types of base oils make up all lubricants: mineral, synthetic and vege- table. Synthetic-based oils tend to cost more upfront but have more consistent properties and are therefore more stable. Additionally, some synthetics can be used in hazardous plant conditions outside the specifi c consid- erations of the machine in question. For example, many synthetic-based oils have a higher fl ash point and are thus less suscep- tible as a fi re hazard. If your plant operates at higher temperatures (from the climate or a process), it likely will be benefi cial to switch to a synthetic oil. Similarly, most synthetics have a lower pour point and are better for machines starting up in very cold conditions. Again, synthetics often cost more initially, but by having better fl uid properties and a longer useful life, they can pay for themselves in short order. e most important property to consider when selecting a lubricant is the viscosity, and the fi rst place to look for assistance when choosing the viscosity is the equipment manufacturer. Even if the manufacturer's recommendation is not always the best advice, it is the best starting point to determine the base range for the machine. For instance, an oil-pumping system may be designed to operate at around 125 degrees F, but at certain times it can run as high as 155 degrees F due to certain plant conditions. e manu- facturer's guide only takes into account the normal operating temperature of 125 degrees F in its viscosity recommendation. To ensure your lubricant remains viable, select an oil that meets both the minimum and maximum operating condi- tions and has a viscosity index (VI) that can withstand condition changes. If you work in a climate that is particularly hot or cold, the manufacturer's recommended lubricant may be incorrect solely because it is assumed the machine is operating in more temperate climates. Temperature is an important factor to consider, because lubricant life is closely tied to operating temperature. Reducing the oil's operating temperature by 18 degrees F will double its life expectancy. is means fewer oil changes as well as less labor and downtime. If the system operating tempera- tures can't be changed, a similar (but lesser) result can be achieved by making certain that the selected lubricant has the right VI additive to allow for all environmental and climate conditions. ere are many other additives and fl uid properties to be considered for a specifi c machine application, but accounting for the viscosity and VI is the most eff ective means to improve lubrication. Some lubri- cant vendors can supply oil and grease with almost any desired package of properties. An easy way to produce cost savings at this stage is by simplifying your overall lubrica- tion order. You may discover that you were needlessly purchasing a more expensive oil or grease. More likely, you will fi nd that most machines can safely use the same type of oil and grease, and another area of savings can be established simply by ordering fewer lubricant types overall. Even if it costs a little more to adjust the oils and greases ordered, savings will be realized when machinery downtime decreases. Reception and Storage After selecting the correct lubricant, the next step is to ensure that it remains the BEFORE 10% MAINTENANCE COST REDUCTION 40% SALES INCREASE $ % of Sales $ % of Sales $ % of Sales Sales $100 100% $100 100% $140 100% Maintenance Costs $20 20% $18 18% $28 20% Material, Labor, G&A, and O/H $75 75% $75 75% $105 75% Profit $5 5% $7 7% $7 5% Impact of maintenance on overall profi tability Approach A Approach B www . machinerylubrication.com | September - October 2019 | 49