The secret to the high-load lubricant-free operation of B filament-wound bearings lies in their use of ultra-strong PTFE fibers with a unique weave.These fibers have a tensile strength exceeding that of conventional PTFE resin fibers by a factor of 20, and are not readily subject to a cold fluid effect at high loads.Thanks to CSB's film transfer technology, these bearings do not require any external lubrication, even during the start-up period.
When bearings begin operating, after a brief period of wear, the PTFE in filament-wound bearings migrates from the inner surface of the bearings to the friction surface of the bearing shaft, where it fills any macroscopic defects in the shaft surface.A small portion of filament-wound bearings is actually worn away, and migrates to the surface of the shaft, where it forms a low-friction PTFE film.This wear is usually less than 0.03 mm thickness, and can be ignored in most practical situations.
As a result, the bearings have an extremely low coefficient of friction under high-load conditions, and suffer only minimal long-term wear.After the break-in period, the wear rate gradually stabilizes, and stays relatively constant throughout the bearing's life.When CRB filament-wound bearings were tested with a pressure of 50Mpa and a 45° pivot angle, it was found that wear was stable at 0.09 mm after 500,000 rotations.
The time needed for break-in is determined by the PV (pressure and velocity) value.The average wear rate will reflect actual operating conditions. Factors that may tangibly affect wear rate include load, speed, shaft and hardness and composition, and smoothness of the shaft surface.To obtain bearings most suitable for your planned applications, please contact CSB's application engineers to obtain even more specified information concerning the break-in period.
While CSB filament-wound bearings can minimize wear to a great extent, bearing wear is inevitably determined by operating conditions as a whole, including speed, sliding distance, and load.After several thousand hours of operation, radial wear due to intermittent rotation or vibration can be ignored.A hard chromium-plated surface offers superb wear performance, and can prevent shaft corrosion.The shafts paired with CSB's filament-wound bearings commonly have surface treatment consisting of chromium plating, non-electroplated nickel plating, or YZD treatment or nitro-carbide coating.