Metal Timing Belts / high temp bushings


Thread Starter

Ken Brown

We are putting together an application where we are required to position a saw carriage within a harsh environment. Ambient temperature is on
the order of 250 degrees F with moderate humidity. Positioning accuracy is lax (+/- .125 inches). The odds that this thing will see any type of regular maintenance is next to zero so we would prefer to use a non-lubricated drive system. Does anyone have any advice on using a
metal timing chain for this kind of application? Forces to move the carriage will be less than 15 pounds with max speeds of 20 inches/second. The idler shaft that will hold the pulley at the end of the carriage should also use non-lubricated high temp bushings. Any and all suggestions are welcome.


Ken Brown
Applied Motion Sytems, Inc.

If I was responsible for building a device to meet the needs you outlined, I would be looking at a ball and lead screw type of drive. I would also use a Teflon type of ball for a few reasons... 1) Teflon will handle the heat you
mentioned with out galling to the shaft after periods of no motion. 2) Teflon inherently provides its own lubrication. 3) Is easy to machine and would allow you to fabricate spares in house. All of this may be moot as you did not detail the travel distances involved (A lead screw would have a finite length and requires supports along its length).

Best Regards... Rick Kelly

Chief Electrical Technician
Natural Cuts
Cheese Operations
Kraft Canada
(613) 537-8069 V
(613) 537-8057 F
[email protected]

Travel would be ~ 4ft, (~1200mm for the rest of the world ; ). Are you suggesting a Stainless ball screw with teflon ball bearings and plastic
nut assembly? Should we use teflon bushings on the ends of the screw as well?