Lubricants: Smooth Operators
March 1, 2011
by Shane Whitaker
Avoiding metal-to-metal contact must be a primary goal of all plant maintenance programs. Lubricants play a major role in preventing that contact, which would lead to serious mechanical issues within a bakery or snack manufacturing plant if allowed to happen. Failure to maintain proper lubrication of processing equipment will cause equipment systems to break down more quickly than anticipated.
“As a rule, lubrication is a lifeblood to all mechanical equipment,” said Darren Jackson, COO of The Henry Group, Greenville, TX. “Production schedules and capacity affect downtime scheduling in plants, which directly influence the amount of time for preventive maintenance. Proper preventive maintenance adds to the life of equipment, and lubrication is a routine part of preventive maintenance.”
In particular, he noted, oven chains in tray ovens require regular lubrication schedules. “Without it, you reduce the life of the chain, rails, sprockets and turning points requiring more frequent rebuilds, so the cost adds up over time,” Mr. Jackson added. “Ensuring that a new oven chain is broken in properly after a rebuild is critical; taking shortcuts only shortens the overall life of the chain. We, as manufacturers, need to continue to develop machines that inherently reduce wear.”
Another idea would be to move to a chain that does not require lubrication (See “Lube-free Conveyorized Oven Chain” on Page 108). But lubricants are not just suddenly going to disappear as a maintenance requirement in bakeries. In fact, Stewart Systems, Inc., Plano, TX, the OEM making the new lube-free oven chain, began offering its own line of lubricants within the past year.
An informed maintenance organization has many considerations when choosing lubricants for plant equipment, according to Bob Whiting, president, Ultrachem, Inc., New Castle, DE. “Downtime is costly and always a concern. Processing equipment is expensive, and OEM warranties are usually an important consideration,” he said. “Being able to use one lubricant for an entire operation would be optimum, but not practical. The average processing plant includes many types of equipment, all with different lubricant requirements. For example, the air compressor that supplies the air for pneumatic equipment will not use the same type lubricant as a hydraulic system or a gear box that powers a mixer.”
A lubricant’s oil base and additive package is specially formulated for a specific application in a bakery, according to Bill Camp, account/customer service manager, Stewart Systems. Because processes in bakeries vary from freezers to high-humidity proof boxes to ovens, he said, different lubricants are needed for the various pieces of equipment.
“Plant engineers should be open-minded to possibly making lubricant changes, if there are better-performance lubricants available that will improve their operations and increase the equipment/chain life while reducing annual costs,” Mr. Camp added. “Switching to higher-grade synthetic lubricants will typically offer better wear protection with less usage, resulting in annual cost savings.”
One of synthetic lubricants’ major benefits compared with petroleum-based products is the reduced lubrication consumption — up to 10 times less in some cases — because of better thermal stability and lower evaporation rates. “Synthetics also offer better wear protection, which results in longer equipment life,” Mr. Camp explained. “So even though petroleum oils cost less, the bakery will spend less money annually if higher-grade synthetics are used because less oil will be purchased and longer equipment life will reduce annual spare part requirements.”
Often, companies base their lubrication purchasing decisions solely on price. “However, more facilities are looking at the total cost, including spares and downtime due to cleaning and part replacement, and are factoring in benefits such as increased component life and reduced usage and selecting the lubricant that brings the best value to their operation,” Mr. Camp observed.
Synthetic lubricants were once regarded as a costly alternative to mineral oils and would only be used in extreme applications, according to Glenn Krasley, Ultratherm’s sales and marketing director. “Today, synthetics are actually lower in overall cost when one considers all the benefits synthetics have to offer,” he said. “Extended drains, lower disposal costs, less maintenance downtime, extended equipment life and energy efficiencies all lead to lower overall cost per gallon when compared to conventional oils.”
Many synthetic/long-life options that are available today that did not exist 30 years ago, noted Jim Girard, vice-president and chief marketing officer, Lubriplate Lubricants Co., Newark, NJ. In addition, he said that food processors can safely and effectively convert to all H1/food-grade lubricants. “That was not the case 30 years ago,” he said.
“In my opinion, all lubricants used or stored within the confines of any food manufacturing facility should be H1 and NSF food-grade-certified,” Mr. Whiting said. “Some feel if there is no reasonable expectation that the lubricant can contact food products during processing, there is no need to use a food-grade lubricant. My belief is that if the lubricant is stored within the facility and accessible to personnel, there is some potential for it to be used inappropriately.”
Jill Dohner, vice-president, Petrochem, Chicago, IL, said the Food Safety Modernization Act signed into law earlier this year gives FDA more authority to do plant inspections, and as such, food plants need to be certain that their lubricants are not contaminants. She pointed out that many companies still use H2 lubricants in ovens because plant engineers believe they are superior; however, Ms. Dohner noted technology has improved in making high-performance H1 oven chain lubricants.
Mr. Girard echoed this sentiment. “All lubricants used should be H1/food-grade. There is no reason why bakeries should use non-food-grade lubricants,” he said.
In the recent past, food-grade lubricants were formulated from straight-grade white mineral oils with little, if any, additives, according to Mr. Krasley. “These lubricants were generally regarded as less robust than their non-food-grade counterparts and labeled inferior to conventional products and were the only options available,” he said. “Synthetic base fluids such as PAOs [polyalphaolefins], PAGs [polyalkaline glycols] and esters, combined with modern additive systems that are H1- and NSF-capable, have greatly improved the life and functionality of today’s food-grade lubricants. Sophisticated synthetic formulations are designed specifically for food-grade applications and offer vastly increased protection and longevity.”
Bakeries do not have to sacrifice performance by switching from H2-approved lubricants to high-performance food-grade H1 lubricants, Mr. Camp said. “High-temperature, polyester food-grade chain oils have been developed in the past two years and perform just as well as the ester H2 chain oils,” he said.
LONGER LIFE LUBRICANTS.
A common issue maintenance staffs have with regard to lubricants is carbonization on the oven chain because of the oil breaking down and having poor thermal stability, according to Mr. Camp. Consequently, he said, properties of a good lubricant are low carbonization, good thermal oxidation stability and evaporation rates, and excellent wear and bearing life protection.
Some of the lubricant qualities most needed in baking and snack manufacturing environments, according to Mr. Girard, are the ability to operate at wide temperature ranges and to seal out airborne contaminants.
Plants need to ensure they are using the proper lubricant for the application to get optimum equipment life and operation, Mr. Whiting added. “Controlling the environment in which equipment operates will greatly enhance the life of any lubricant,” he added. “Time, temperature, load and cleanliness all have an effect on a lubricant’s lifecycle. For instance, a gear box that operates at or over its intended temperature range will greatly diminish the lifecycle.”
Mr. Camp suggested that maintenance organizations get educated by their lubrication specialist or OEMs to lengthen the life of these products. “Ask OEMs which lubricants they recommend for the various pieces of equipment, and be sure to get recommendations by someone who is familiar with the bakery environment,” he added.
Although lubrication may not be the most exciting of subjects, suppliers continue to offer new and improved products that can protect equipment longer and are safe in the food processing environment. Thus, it is always wise to investigate the latest lubricants available for the baking and snack industry. Look for a showcase of lubricants designed for the baking and snack industry in a future edition of Baking & Snack’s weekly Operations Update e-newsletter. Subscribe to this or any of Sosland Publishing’s e-newsletters today.
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