SF-2 Characteristic Of Performance
SF-2 is triple-layer self lubricating material that can fill modified POM plastic as su rface layer,it is benignant boundary lubrication material,therefore ,it is particularly applicable high-load low-speed rotating and wing movement, as well as in the condition that frequent loaded start-stop is the requirement while hydrodynamic lubrication membrane is difficult to form, in the parts such as bearing, thrust washer, sliding block, ball socket and so on, SF-2 can take full advantage of less grease to work long time without lubrication maintenance under boundary lubrication condition, But under oil-free condition ,SF-2 the frictional behaviou and permissible PV value is relatively low, so generally storage pit can be formed on the plastic surface, where lithiumbased lubricant grease or silicone grease and so on should be applied when being installed.

SF-2 Wear Regularity
SF-2 material follows special wearing rule as shown in Fig.4, infinitesimal abrasion can occur in R phase when being applied with grease and then being installed, But after the R phase, the boundary lubrication condition will disappear and wearing will be exaggerated. If you do refill with oil,the product can be drastically held by non-remarkable wearing and its life will also be greatly extended. Therefore the advantage of SF-2 material is that oil shall be added with an interval of R, which is remarkably longer that that of R other metal materials. It is approximately five times long.
When SF-2 bush is installed with application of grease such as lithium-based or silicone grease,its service life varies from the PV value under-working condition, for instance, when PV value is about 2.5MPam/s, its service life will be about 200hr; when PV value is 0.1Mpa-m/s, its service life can be above 10,000hr (see the table for details) The cycle R of lubrication maintenance of SF-2 bush is about the half of its service life. For instance , when PV=25Mpam/s, it is required to be oil-lubricated every 100hr.

Max.Load	Static	250N/mm2	Friction Coeff.	0.05∽0.25μ
	Dynamic	140N/mm2	Speep limit	0.25m/s
	Oscillating	60N/mm2	Thermal conductivity	2.03Kcal / M.br.c
PV limit	Dry	2.8N/mm2.m/s	Coeff. Of linear expansion	51×10-6peroC
	Oil	22N/mm2.m/s	Initial pre-lubrication at assembly required
Temp.limit		-40oC~+130oC