Case Study Lead Screws

Benchmark Imaging Group is a well-established X-ray equipment manufacturer and reseller. Their engineers have used the latest tools and technology to service and repair thousands of used X-ray equipment.

The owner and operating manager, Pete Schliebner, has been an X-ray service engineer for twenty three years. His years of experience have given him the ability to troubleshoot most X-ray equipment related problems, but he was stumped when it came to a problem involving the proprietary industrial machine that his company manufactures, the Merlin Laue System. The parts positioning subsystem of the machine consists of three motorized tables, with stepper motors and lead screws. One of the tables travels vertically. Unfortunately, the vertical table’s operation created a strong harmonic vibration as the nut traveled along the lead screw; producing an unbearably loud screeching noise. “For 15 years, we have been trying to find a solution to eliminate the squealing,” states Schliebner.

The vibration and high-pitched squeal are not just acoustic problems, but can cause physical damage to the machines, as well. Schliebner noticed that as the machines aged, the high-pitched squeals grew louder and more intense. He knew that gaps, which exist between the nut and the threads of the lead screw, were not adequately lubricated, resulting in metal-to-metal contact which created a harmonic vibration. The noise getting worse indicated that the vibration was causing wear to the nut and the thread, and that over time this friction could cause the lead screw to break down.

In order to solve this issue, Schliebner tried using dozens of different lubricants. “We’ve used just about every type of grease we could find.” One of which was an oil that was recommended which required the service engineers to re-lube the machines at least once a week. It was not only a hassle to apply the oil every week, but the product did not even work. Schliebner recalled, “All it did was make a huge mess, and it never did stop the squealing, even when you first put it on.”

Schliebner decided to contact the manufacturer of the lead screw tables for their recommendation. They recommended using Magnalube-GX, which had worked very well to dampen vibrations in their other products. After applying Magnalube-GX onto one of his machines, Schliebner noticed an immediate difference. “It is the first product that we have ever used that actually worked. So now we apply it to all of the vertical lead screws on the machines that are in the field already and the ones that we are currently building.” Since he switched to using Magnalube-GX about a year ago, Schliebner says he knows of only one customer that needed to re-grease their lead screw.

Magnalube-GX has a molecularly bound MOLY-PTFE formula that absorbs vibrations and does not allow any metal-to-metal contact. It seals the gaps between the nut and the lead screws while still providing lubrication for the nut to travel smoothly. Its tackiness and exceptional film strength allow it to stay where you put it, unlike other lubricants that migrate. Magnalube-GX was exactly what Benchmark Imaging Group was looking for, providing them a way to make a better, more reliable product. Their customers can now enjoy the perks: less maintenance and a significant reduction to noise.