When you forget to change the oil in your car’s engine, it won’t take long before you start having numerous other engine problems. Without the oil to lubricate the metal-to-metal contact, your car’s engine will get hot and dirty, parts will break, and it may even seize up to the point of needing costly major replacements.
Letting your ball screws go without scheduled lubrication and ignoring the grinding metal-to-metal contact essentially has the same effect as not changing your engine oil, and usually results in hours of unanticipated downtime servicing your workplace machinery.
Ball Screw Wear Image by Machine Design
Fortunately, keeping a constant thin film of lubrication, oil or grease, solves a multitude of unwarranted problems and extends the screw’s life and work efficiency by reducing friction and minimizing torque.
Applying LubricationBefore you apply any lubrication, whether you choose grease or oil, make sure the ball screw is thoroughly clean and dry. Get rid of any buildup from the grease or oil that’s been sitting over the past few months so it doesn’t get caught between the balls or on the screw leads, damaging the screw and its connected parts.
Don’t apply too much lubrication at once. Rather than a ball screw that is dripping wet and creating a mess on the rest of the machine, make sure that the screw is simply wet to the touch – having just enough lubrication to prevent dry metal-to-metal contact.
Grease vs. Oil
Knowing that you need to lubricate your ball screws on a semi-regular basis is only half the battle. The other half is figuring out exactly which type of lubrication to use.
Oils are sometimes considered lower-maintenance than greases, since they’re less likely to create a buildup and tend to stay inside the ball nut much better than greases do.
Oils usually require a pump and filtering system, and work well with low to moderate operating speeds, load sizes, and temperatures. However, if any of these three factors are too extreme, it can render the oil coating useless, causing metal-to-metal friction and damage.
Greases, on the other hand, can go directly onto the screw itself or into the ball nut if it has open holes to pump the grease through. Greases can also handle high speeds and be used with additives to create synthetic lubricants that can handle more extreme temperatures, load sizes, and speeds. However, greases shouldn’t be used with molybdenum disulfide or graphite since they create friction levels that are actually too low.
Our Product RecommendationsAt Misumi, we recommend lubricating ball screws with a normal workload every six months and ball screws with a heavy workload every three months. The friction and rolling resistance between the grooves and the ball bearings stays low when you re-lubricate at this frequency, especially if you carefully select the right lubrication for your specific job.
We offer three types of grease specifically tailored for different types of working environments:
- L Type: linear ball bushings, stroke ball bushings, linear rotary bushings
- G Type: linear miniature guides
- H Type: linear guides, precision ball screws, rolled ball screws
0 nhận xét: