For lubricated bearings.

Bear Brand TUFNOL is a cotton fabric grade specially formulated for use as a lubricated bearing material.  It has enhanced wearing properties  and dimensional stability and gives excellent performance in a multitude of bearing applications, using water as a lubricant, or more conventional oils or greases.  The low water absorption properties allow reduced clearances in bearings and also provide enhanced electrical insulation properties.

What is Bear Brand used for?

Bear Brand is used for a wide range of wearing and bearing applications, such as oil or grease lubricated bearings, slideways, water lubricated marine bearings, pump sleeve bearings, seal rings, mixer bearings, slipper pads, rolling mill bearings, guide bushes and a wide variety of components which are lubricated by the water-based process fluids in which they operate.

TYPES AVAILABLE	Sheets	Rods	Tubes	Other sections
Natural colour	Yes	Yes	Yes	Yes
Graphite-impregnated Bear Brand	Yes*	Yes*	Yes*	Yes*
Molybdenum disulphide impregnated Bear Brand	Yes*	No	No	No

* Minimum order quantities may apply.

Click here for Bear Brand TUFNOL STANDARD SIZES

SPECIFICATIONS for Bear Brand TUFNOL

BRITISH STANDARDS	Current Standards	Recent Standards (now obsolete)
Sheet	Since the withdrawal of BS 2572, no British Standards or other national standards are applicable to Bear Brand Tufnol.  This grade is therefore now manufactured to in-house quality specifications of Tufnol Composites Ltd, based on the former BS 2572 Type F2/1.	BS 2572 Type F2/1
Round Rod	BS EN 61212-3-3 Type PF CC 42	BS 6128 Part 2 Type PF CC 23
Rectangular Bar	BS 6128 Part 4 Type PF CC 44
Hexagon Bar	BS 6128 Part 6 Type PF CC 64
Round Tube	BS EN 61212-3-2 Type PF CC 32	BS 6128 Part 9 Type PF CC 93
Rectangular Tube	BS 6128 Part 13 Type PF CC 133

PHYSICAL PROPERTIES

Bear Brand TUFNOL Sheet

PROPERTY	TYPICAL RESULT	UNITS
Cross breaking strength	110	MPa
Impact strength, notched, Charpy	11.0	kJ/m2
Compressive strength, flatwise	290	MPa
Compressive strength, edgewise	210	MPa
Shear strength, flatwise	100	MPa
Tensile strength	58	MPa
Young's modulus	6.6	GPa
Water Absorption
- 3mm thk.	45	mg
- 6mm thk.	80	mg
- 12mm thk.	100	mg
Electric strength, flatwise in oil at 90ºC
- 3mm thk.	3.9	MV/m
- 6mm thk.	3.5	MV/m
Electric strength, edgewise in oil at 90ºC	15	kV
Insulation resistance after immersion in water	5x1010	ohms
Relative density	1.32	-
Maximum working temperature**
- continuous	120	ºC
- intermittent	130	ºC
Thermal classification	Class E	-
Thermal conductivity through laminae	0.29	W/(mK)
Thermal expansion in plane of laminae	2.7	X 10-5/ K
Specific heat	1.5	kJ/(kgK)

Test methods as BS EN 60893-2, where applicable.

Bear Brand TUFNOL Round Tube

PROPERTY	TYPICAL RESULT	UNITS
Axial compressive strength	170	MPa
Cohesion between layers	110	MPa
Water absorption	2.0	mg/cm2
Insulation resistance after immersion in water	1x108	ohms
Relative density	1.32	-

Test methods as BS EN 61212-2, where applicable.

Bear Brand TUFNOL Round Rod

PROPERTY	TYPICAL RESULT	UNITS
Flexural strength	110	MPa
Water absorption	2.0	mg/cm2
Insulation resistance after immersion in water	5x107	ohms
Axial electric strength in oil at 90ºC	6	kV
Relative density	1.32	-

Test methods as BS EN 61212-2, where applicable.

**Users of highly stressed components at temperatures approaching the maximum are recommended to seek further advice from Tufnol Composites Ltd.

Click here for TUFNOL Bearing Design page

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A full machining service is available from Tufnol for this and many other engineering plastics and composites.

Tufnol Composites Ltd, Wellhead Lane, Perry Barr, Birmingham B42 2TB, United Kingdom.

Quality Registration BS EN ISO 9001:2000, BS EN 9100:2003 and AS 9100 Reg. No. FM 90942

The information given here is believed to be correct, but completeness and accuracy are not guaranteed. The user shall be fully responsible for determining the suitability of products for the intended use.