Page 33 - MetalForming Magazine August 2022

“When oil is thought of as a com- ponent of the equipment and not just a commodity, then oil quality will take on increased importance,” Dinwiddie says. “If a higher-quality oil is utilized that may not need to be changed every 10 years, instead of an oil that needs changing every year, then lubrication will intersect the green evolution. Keeping an open mind regarding this topic also will benefit metal forming operations with substantial cost savings
tion—because all of these factors are being squeezed. We see lubricants as way to address a lack of resources and to raise efficiency.”
Often the goal is to illustrate how a higher-performing lube can improve efficiency and extend the operating life of the hydraulic fluid, thereby extend- ing the period between drains. Metal formers would be wise to perform fre- quent and detailed oil analyses, Din- widdie and Vicars say, to validate oil
veys evaluating the true cost of poor lubrication finding that while most manufacturing facilities spend less than 0.5 percent of their maintenance budg- ets on hydraulic oil, the downstream effects of a poor lubrication strategy can impact as much as 30 percent of the plant’s total maintenance costs.
“The surveys also find that as much as 70 percent of lost machine life and machine failures result from premature component wear due to poor lubrica-
and less maintenance.”
The Right Lube,
and the Right Amount
“A plant survey may help reduce the amount of each machine lubricant needed and help ensure that the right lubricant is being used for the specific application,” explains Vicars. “From there, shops should seek to optimize viscosities specific to each piece of equipment. All of these actions will save money and improve production turns.”
When asked to describe finite exam- ples that indicate how a conscientious approach to lubrication has improved production efficiency, Dinwiddie explains:
“If a hydraulic system is using a hydraulic oil with a viscosity of ISO 68 but the pump manufacturer calls for an oil with an optimum viscosity of 25 to 30 cSt and the system is operating at 130 F, then the optimum viscosity would most likely be ISO 46. This would improve efficiency because the pump will not have to pump such a viscous fluid all day long. The efficiency gain also will result in power savings and possibly an improvement in produc- tion turns.”
When Dinwiddie and Vicars visit with stampers, they start by asking a lot of questions.
“With hydraulic systems—say hydraulic presses or die cushions, or gear or clutch oil—it doesn’t end with lubricants,” Vicars says. “We also dig into cycle times, productivity issues, labor constraints, power consump-
condition, and use the information to reduce equipment operating temper- ature, reduce energy consumption and save labor hours related to equipment maintenance. One overriding goal: Extend drain intervals for as long as possible.
“It’s a lot more time-consuming to change machine oil every 6 months over a 3-yr. period, for example,” Vicars says, “than to change it once every 3 years based on oil analysis from sam- ples pulled every 6 months to validate the lubricant’s condition.”
The Downstream Effects of a Poor Lubrication Strategy
Dinwiddie and Vicars point to sur-
tion management,” Vicars says. What’s the overriding root cause? “Varnish,” Dinwiddie offers. “This
is particularly true with servo valves, which must not have any varnish on them in order to continue to operate as designed. Varnish—or oxidized oil— may form only very lightly yet can cause a servo valve to stick or otherwise not function properly. This can lead to poor die-cushion performance, pre- mature die wear and poor part quality. And, consider the cushion on the lead press of a tandem line—varnish on the servos can lead to a poor-quality initial part from the first press and ruin the die. When the bad part exits the last press, the maintenance team may
30 MetalForming/August 2022
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The wrong machine oil can cause varnish buildup in the hydraulic circuit, particularly on servo valves, and lead to poor machine operation and potentially poor part quality. Shown is an aluminum beaker oxidation test on ISO 46 fluids, comparing varnish buildup when using a conventional hydraulic fluid (left) and a synthetic multi-viscosity fluid (right).