Page 198 - The Tribology Handbook

97 Friction clutches

Table 7.3 Clutch facing materials and their applications
TVpe Uses
Woven Industrial band, plate and cone clutches-cranes, lifts, excavators, winches, machine tools and general
engineering applications
~~
Asbestodnon asbestos Mainly automotive and light commercial vehicles, agricultural and industrial tractors
wound tape and yarn
Moulded Automotive, commercial vehicles, agricultural and industrial tractors
Sintered Tractors, heavy vehicles, road rollers, winches, machine tool applications
Cermet Heavy earth-moving equipment, crawler tractors, sweepers, trenchers and graders

Oil immersed
paper Automotive and agricultural automatic transmissions
woven Band linings and segments for automatic transmissions
moulded Industrial transmissions and agricultural equipment
sintered Power shift transmission, presses, heavy-duty general engineering applications

Facings are available in a wide range of sizes 75-610 mm outside diameter, and the designer should consult with the friction
material manufacturer to determine which stock size would best fit his requirements.

Table 7.4 Friction, and allowable operating conditions for various clutch facing materials
Temperature, "C Working Power
Operating dy CL pressure rating
Maximum Continuous kN/m2 W/mm2
LIGHT DUTY
Woven 0.35-0.40 250 150 175-520 0.3-0.6
Mill board 0.40 250 150 175-700 0.3-0.6
MEDIUM DUTY
Asbestodnon asbestos
wound tape and yarn 0.40 350 200 175-700 0.3-1.2
Moulded 0.35 350 200 175-700 0.61.2
HEAVY DUTY
Sintered* 0.36/0.30: 500 300 350-2800 1.7
Cermet? 0.40 700-1400 4.0

OIL IMMERSED
Paper 0.1 1 700-1750 2.3
Woven 0.08 700-1 750 1.8
Moulded 0.04 700-1 750 0.6
Moulded (grooved) 0.06
Sintered 0.10/0.05: 70W200 2.3
Sintered (grooved) 0.10/0.06: 700-4200 2.3
* Facings are sintered on to core plates or backing plates.
t Supplied as buttons in steel cups.
: First figure static, second dynamic coefficient.

B7.8