Lack of maintenance on processing equipment can cost a company a lot in energy, processing inefficiencies, and downtime. The flip side, proactive maintenance, is almost purely positive and can pay big dividends in the long run.
Processing machinery that is maintained properly typically means decreased energy consumption, increased productivity, better part quality, and reduced downtime, giving the equipment greater availability. While few people think of machine maintenance as connected to “sustainable production,” a recent Aberdeen Group survey on the latter showed there is a direct correlation between how well a processor maintains his equipment and how well his company looks on its bottom line.
Operational efficiencies and overall costs to manufacture are tied closely to processing equipment. Paul Caprio, president of KraussMaffei (Florence, KY), which manufactures injection molding, extrusion, and polyurethane processing machinery, says while KraussMaffei’s customers are concerned with energy consumption, the issue remains secondary to precision and output. “Even though energy savings is a buzz word, quality parts and high productivity are what count on the manufacturing floor,” says Caprio. “Our customers are more attuned to making the machine run better.
”That said, Caprio adds that many customers are getting rid of older injection molding machines that tend to consume more energy—particularly hydraulics—and replacing them with new or newer machines that have more energy-efficient motors and pump systems.
Aberdeen Group’s Sustainable Production report revealed that its “Best-in-Class” respondents are integrating sustainable features across their operations, “taking into consideration information related to energy, emissions, product, process, and employee safety—while optimizing production, maintenance, and engineering processes.” One example the report cited is including energy as one of the factors, in addition to asset condition, to monitor when scheduling maintenance.
Who will handle your maintenance?
Machine maintenance always has been recognized as critical to quality parts and high productivity, but one thing that has changed, notes KraussMaffei’s Caprio, is the greater reliance on machine OEMs to supply that maintenance.
“There’s no question that over the past two years, the customer base is absolutely relying on the machine manufacturer to handle the preventive maintenance on the equipment,” says Caprio. “Many processors have gotten so lean in laying people off and other cost-cutting measures that they’re not doing machine maintenance in-house. One of the safety valves KraussMaffei offers is planned regular checkups, quarterly, semi-annually, or annually.”
His firm is not alone; maintenance and service programs at most processing machinery manufacturing firms used to play second fiddle to new equipment sales, but now often are almost as important as a source of revenue.
The transition at both processors and their suppliers is not entirely negative, since it gives each good reasons to pay closer attention to machine maintenance programs. That may be more important than ever now, notes Jimmy Langsdon, president of Columbia Machine Works Inc. (Columbia, TN), whose business specializes in machinery maintenance and repair, including injection molding machinery. He notes that many times, especially when the economy is slow, companies get too lean.
“A lot of people make the mistake of cutting their maintenance budget when dollars get tight,” says Langsdon. “This is the worst thing you can do. Keeping your machinery in tip-top shape is the most important thing to your business.”
So important is it, in fact, that Scott Paulson, president of Paulson Training (Chester, CT), which offers courses for plastics processors, says his company has integrated machine maintenance into a variety of its injection molding training programs. “Maintenance is part of the efficiency equation. Maintenance affects downtime—which is a killer—so it’s vitally important,” Paulson says. “We have a [training] program on machine maintenance and how efforts in this area can increase efficiency.”
Langsdon says the primary problem he sees with molding machine maintenance is the tendency to cut obvious corners. “We see a lot of molding machine failures due to poor lubrication, either a lack of lubrication or dirty lubricant,” he comments. “When we rebuild injection molding machines, common things we see are those bearings that are worn out due to lack of lubrication.”
Andy Routsis, president of A. Routsis Assoc. Inc. (Dracut, MA), which provides online plastics processing skills development and training, agrees with Langsdon’s comments and adds that the problem is persistent, even with all-electric machines. “All of them have toggle clamps,” notes Routsis. “We have a program for training machine maintenance personnel, and I cover the things that aren’t typically covered in the OEM’s maintenance manual.”
There’s definitely a huge payoff in maintaining processing machinery, and often it’s the areas that people don’t think about that can cause the biggest problems, like lubrication. “They don’t lubricate the machine properly—that’s always a problem. Another big one is leveling, particularly in the larger-size presses like a 400-ton running an 8-second cycle—that machine is rockin’ and rollin’,” emphasizes Routsis, who recommends a bubble level or digital level, or better yet a laser level, to check the level of a machine and to re-level it periodically.
Simple steps make big differences
Another problem that arises on new equipment has to do with the laws regarding shipping a machine. “The machinery maker will do a run-off to test all the functions of the machine before shipping to make sure it’s running correctly,” explains Routsis. “One of the things it must do by law is empty the machine of oil. From the run-off, you get a lot of chafings from the rubber hoses—they fill up with oil—and it leaves the grit. Before refilling the machine with oil, pull the tank plate, wipe out the tank, and then swap out the filters. Most people figure it’s a new machine, so why do they have to do that? But it’s important.”
Routsis also recommends checking the platens for simple flatness, something that he finds rarely done. “Take a 12-inch or 36-inch steel ruler and lay it across the stationary platen by the locating ring,” he suggests. “If you see a gap between the platen and ruler, you know it’s not flat.”
Additionally, he adds, check the movable platen supports. The reinforcements on the platens should be cast, not machined. “You want the give,” says Routsis. “We talk all about these things in the maintenance training course. It’s always something basic that fails.”
When times are slow, Langsdon suggests that’s the best time to perform preventive maintenance on machinery and to make good use of employees’ efforts. Still, he notes, for many people it takes a “catastrophic event” before they pay attention to their machinery maintenance needs. “The key word in all of this is preventive,” he stresses. “If you wait until the machine can’t function, it’s too late. Now you’ve gone from maintenance to a repair, and the cost is a lot more.”
Langsdon says that a molding machine in good repair operates at maximum efficiency and there also are power savings to be realized. “We had the Tennessee Valley Authority (TVA) come in and do an audit for us, and just in air leaks alone we were losing $8000 a year. And that’s just because of leaky air! It’s the little things that get people and cost them a lot.”
KraussMaffei’s Caprio advises processors to schedule planned preventive maintenance (PM) because that is more conducive to higher uptime on machinery and fewer mid-production interruptions due to equipment going down. “Our customers tend to be getting bigger with acquisitions and expansions, so uptime is critical to them. If they have the equipment OEM handle the calibration services and other PM services, they can often prevent unplanned major equipment failures. Clamp downtime is key, and most people understand that maintenance is key to preventing it.”