SKF_kluzna_loziska
description
Transcript of SKF_kluzna_loziska
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SKF PTFE CompositeThe long runner
Main applications1)
SKF PTFE Composite dry sliding bear-ings are suitable for applications wherethe load and self-lubrication requirementsare high.
Examples of applications are:
automotive applications materials handling equipment home appliances and consumer goods textile machinery
Lubrication
The PTFE-based sliding surface permitssmooth, low-friction operation withoutlubrication or maintenance. During therunning-in phase part of the coveringlayer of SKF PTFE Composite dry slidingbearings is transferred to the mating sur-face and forms a physically bonded lubricant film.
The presence or continuous supply ofoil or other non corrosive fluids may beadvantageous and improve the perfomanceof these bearings.
1) The performance of SKF PTFE Composite bearings depends on the interaction of load, lubrication, surface roughness,sliding velocity, and temperature encountered in specific applications. Note: Because of the lead content, SKF PTFE Composite type B should not be used in contact with food, beverage or pharma-ceutical products. Try to use SKF PTFE composite type E, SKF POM or Stainless Backed Composite bushings instead.
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Long maintenance-free operatinglife due to low friction
In applications where other materials haveshown insufficient operating life SKFPTFE Composite dry sliding bearings canbe the solution. SKF PTFE Composite isspecially designed to operate withoutlubricant and is particularly suited forhigh load/medium speed applications. SKFoffers a full range of cylindrical bushingsin accordance with ISO 3547 and DIN1494 as well as flanged bushings, thrustwashers and strip.
SKF PTFE Composite bearings offer many features and advantagessuch as:
maintenance-free operation very good frictional properties high load capacity operating temperatures up to 250 C sliding velocity up to 2 m/s small operating clearance
Material
SKF PTFE Composite dry sliding bearingscombine the mechanical strength of steelwith the low friction of a PTFE-basedself-lubricating sliding layer. The inter-mediate layer of porous tin bronze guaran-tees a strong bond between the backingand sliding surface and also improves thedissipation of heat generated during opera-tion. The bearing is available in two ver-sions. One with a sliding layer without anylead. This version has the suffix E. Anotherversion where the sliding layer contains a minor amount of lead incorporates thesuffix B. To protect the bearings fromcorrosion the steel backing is tin-plated.All SKF PTFE Composite dry slidingbearings can be machined, except for thesliding surface. however, a calibration ispossible within certain limits.
Characteristics:
Permiss. load (dyn/stat), N/mm2 80/250
Permiss. sliding velocity, m/s 2,0 (p 1,0)
Friction coefficient 0,03 .. 0,25
Temperature range, C 200 .. +250
Application recommendations:
Shaft tolerance f7 h8
Housing tolerance H7
Shaft roughness Ra, m 0 .. 0,4
Shaft hardness, HB 300 600
Cross section of SKF PTFEComposite
PTFE
tin bronze
copper layer
sheet steel backing
copper layer
tin layer