Up Time Magazine - February/March 2009 - (Page 32) have lubricity properties superior to conventional mineral oil and unconventional hydrocracked stocks. These fluids provide better surface protection with less bulk oil requirement. Consequently, a lower viscosity grade may be adequate to provide similar levels of component protection versus a mineral oil option. The lower viscosity also enhances flow rate, an important characteristic for heat removal, which further enhances energy efficiency. A similar impact may be experienced with the use of ester cylinder feed lubricants in high pressure process gas applications. The combined lubricity and polarity of ester stocks make these ideal choices for cylinder lubrication. Volumes and viscosities can be reduced, providing reduction in parasitic energy losses from friction and viscous drag. Proving Energy Conservation in Production Machines – Documenting energy improvement results is not difficult, but it does warrant careful planning and measurements. It is essential to compare similar conditions when making final conclusions. Steps to consider during the evaluation process should include: 1. Develop the data collection plan, and put it in writing. Develop the criteria for measurement and evaluation before the process begins. 2. Identify a, or multiple, machine(s) that operate with a narrow range of load, speed and throughput variability. Fluctuations will complicate test cycle comparisons. 3. Verify that the lubricant in use for the select machine (call it Product A) is, in fact, the correct type and grade of product for the application. (visit www. precisionlubrication.com for additional information concerning precise selection of lubricants.) 4. Collect process data. At a very minimum, conduct energy readings (amps) for a period of at least 30 days. It would be best to coincidentally record ambient temperatures, operating temperatures vs ambient, machine loads, machine throughput (speed, units of production, RPM, etc…) and/or other process values. Mechanical conditions and changes should also be observed and documented. All maintenance conducted on the machine during the test period should be documented. 5. Collect mechanical data. Data that is relevant could include sump, motor, drive, and bearing temperatures (thermal images), vibration levels and oil analysis data. All of the sample collection methods must be highly repeatable in order for the data to be dependable. Also, a sample set of less than 30 readings can bring the results into question. It is preferable to have too much data rather than too little. 6. Make the conversion to the alternate product (Product B). Make sure that the sump is completely clear of Product A, and that no other mechanical or electrical changes have been implemented that might impact the operation of the machine. 7. Repeat the data collection activity and compare the results. 8. Readings should be converted to monetary terms. frequencies for their slow rotation machines are too short, and the frequencies for their high speed (high nDm) applications are much too long. Balancing grease relubrication intervals alone may free up labor needed to make other systematic lubrication program improvements. 5% - Use of Automation for Short Term Grease Intervals. Grease replacement activities with an interval shorter than seven days should certainly be evaluated for automatic lubrication, either in the form of a single point grease cup, or in the form of simple multi-point systems. The choice is based on a cost comparison for installation and long term maintenance. 20% - Operator Based Care, Including Sump Level Checks and Top-up Activities. Level checks and corrections can, and should, be fulfilled by operators. While it is clear that operators are always busy, part of the operator’s role should be to visit the machines, observe their condition, check the levels and report any observed problems. Organizing this task into routes is time consuming but not difficult, and should be done whether operators are involved in top-ups or not. 10% - Implanting Aggressive Oil Condition Control (filtration, cooling). Lubricant sump change intervals could be safely extended in many applications by a factor of three simply by cooling and cleaning the sumps. The relationship between wear debris, heat and oil oxidation is proven and intuitively obvious. Just 10 years ago, the standing practice for most facilities was to change oil on an annual basis. Integrated into the lubricant analysis program, lubricant sump filtration requires effort while the plant is operating, but returns highly valuable labor back to the planning department during outages. The few items noted above account for 50% of the labor expected for machine lubrication. Freeing this labor for other purposes may require capital (for tools and systems) and certainly will require a change in mindset. During the evaluation of practice efficiencies (for a safe return of labor to the maintenance department), plant engineering should simultaneously redefine inefficient practices to reflect a plant ‘Best Practice’. Energy Savings Potential from Lubrication Program Process Improvements The value of process improvement may be worth every bit of savings derived from superior lubricant performance. Process improvements considerations should address: • Using tools and technology (modernization) to replace human labor. • Efficiency of the selection of tasks in total for machine care. • Efficiency of each required task versus the actual scheduled tasks. Labor Utilization Improvements through Modernization – A large percentage of lubrication programs operate on automatic pilot. When the practices are highly refined this can be a good thing. When practices are not, net labor hours required to fulfill practices tends to be high, and the results may not even cover the minimum requirements. Labor savings potentials are numerous. Potential for savings include: 15% to 20% - Efficient Grease Relubrication Frequencies. It is common for grease relubrication practices to be inconsistent with component manufacturer’s requirements. Calculation of intervals based on machine operating environment and characteristics is an important first step. Reliability engineers are often surprised to learn that the scheduled Energy Savings through Material Conservation If the engineering department executes the february/march 2009 32 http://www.precisionlubrication.com http://www.precisionlubrication.com
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