Teflon Disk In Place of a Slew Bearing
Teflon Disk In Place of a Slew Bearing
(OP)
I am using a steel plate resting on a teflon disk in place of a slew bearing. The material in contact with the teflon is steel. I know that the co-efficient of friction for teflon on steel is pretty low but is there any type of lubricant that would make it even lower? I have looked and looked but can't find the answers I need. Any help/guidance would be much appreciated!!





RE: Teflon Disk In Place of a Slew Bearing
Mike Halloran
Pembroke Pines, FL, USA
RE: Teflon Disk In Place of a Slew Bearing
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RE: Teflon Disk In Place of a Slew Bearing
Mike Halloran
Pembroke Pines, FL, USA
RE: Teflon Disk In Place of a Slew Bearing
Bunting Bearings Catalog
There are thrust bearing pressure values listed.
Guidance with teflon is not possible like with a conventional slewing bearing. Once some eccentricity creeps in, the teflon can move where it wants. Hard to say whether teflon will perform without seeing some details about your application. Some sort of teflon flanged sleeve bearing might serve your purposes if the PV values concur.
RE: Teflon Disk In Place of a Slew Bearing
B. What Mike said about the finish of the steel - also bare steel may corrode over time (increasing friction) so what plating does it have (if any) as that will impact things.
C. Anecdotal information from an old colleague suggested that PTFE on UHMWPE was actually lower coefficient of friction than PTFE against PTFE.
D. If the answer to A is 'no' consider materials such as Turcite or PTFE impregnated acetal and similar.
What is Engineering anyway: FAQ1088-1484: In layman terms, what is "engineering"?
RE: Teflon Disk In Place of a Slew Bearing
HMWPE is probably better. It is a little higher friction, but it is much harder and won't displace and resists embedment.
The only application I've seen where teflon was chosen as a high load bearing material was replaced with greased bronze soon after.
No matter what, I expect the friction to be 10 to 100 times what a roller/ball bearing produces.
RE: Teflon Disk In Place of a Slew Bearing
For a particular carbon-filled TFE with which I have some experience, there was a 'sweet spot' at around 100 psi, above which the wear rate (at low speed) was excessive, and below which, in my particular special case, the leak rate between a stainless plate and plastic surface, both lapped to a couple of light bands, became excessive.
YMMV.
Mike Halloran
Pembroke Pines, FL, USA
RE: Teflon Disk In Place of a Slew Bearing
RE: Teflon Disk In Place of a Slew Bearing
However, as you've done similar before and it worked, I'd look again at suggestions of both surfaces being low friction material of some kind.
Have you tried googling, a quick search got me:
http://machinedesign.com/mechanical-drives/enginee...
http://info.craftechind.com/blog/bid/259158/Top-5-...
http://www.glt.ibg-monforts.com/en/ptfe-bearings-g...
http://www.tss.trelleborg.com/remotemedia/media/gl...
http://mtsandtg.com/system/ckeditor_assets/attachm... (mentions specific lubricant at the end)
What is Engineering anyway: FAQ1088-1484: In layman terms, what is "engineering"?
RE: Teflon Disk In Place of a Slew Bearing
RE: Teflon Disk In Place of a Slew Bearing
http://www.igus.com/wpck/3734/iglidur_prt
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