Document 2G27obJRVVz7jLBmwm6M7eDL
i4)ex.
... ... --
An 1C Industries Company
Friction Products Division
1827 POWERS FERRY RD, BUILDING 20, MARIETTA, OA 30067
Asbestos-free brake linings turn to fiber glass
Asbestos, a material whose name means "incombustible'' in ancient Greek, was the material of choice for manufacturing brake linings until recently. The fibrous mineral has excellent heat resistance, tensile strength and flexural strength characteristics, and. it is easily processed Into brake linings.
Now, however, brake lining manufacturers have de
veloped asbestos-free materials. No material was overlooked as a possible replace
ment for asbestos. The search included fiberglass, the material the Friction Products Division of Abex Corpora
tion, Winchester, Va., settled on as the best asbestos replacement. The company is using fifcifer glass rein
forcement in its ABEX EXL (extra long life) brake linings. ABEX EXL brake linings are available'' for auto
mobiles, trucks, off-road vehicles and industrial brakes
-- all of the brake products it traditionally offers in asbestos. ABEX EXL friction material is a matrix cen
tered around PPG chopped strand in a thermosetting polymer system.
Abex, a member company of 1C Industries, has been manufacturing brake linings since 1902, when it began
producing brake shoes for locomotives and railroad
cars. Today, it is the world's largest producer of friction
materials, with 16 plants throughout the world supplying
brake linings for automobiles, trucks, airplanes, off-road vehicles, material-handling equipment and industrial machinery.
Abex began investigating alternate materials for as
Abex EXL brake linings are manufactured from a friction material whose matrix Is centered around chopped strand fiber glass in a thermosetting polymer resin.
bestos when higher braking temperatures and higher wear rates became apparent as vehicles were down sized and tractor/trailer trucks were made more stream-
lined in response to government-mandated fuel-
efficiency goals and the public's demand for fuel-efficient cars.
Smaller cars, more aerodynamic design, smooth-rolling radial tires and front-wheel-drive necessitated
smaller and lighter brake components and overall brake system redesigns. The typical 1983 disc brake rotor is two
Inches smaller and 15 pounds lighter than its 1973
counterpart. Brakes on compact and subcompact cars,
therefore, absorb more energy than before. Brake and automobile manufacturers began to look for environ
mentally acceptable materials that performed even bet
ter than asbestos.
Truck brakes today also operate at higher tempera
tures, mainly because of improvements that have re duced drag and improved fuel economy. Aerodynamic
flaring, lower axle ratios, radial tires and declutching fans have reduced drag in tractor/trailers by about 100
horsepower over the past six years. Today, a typical
tractor/trailer descending a three percent grade must
develop 369 percent more brake horsepower to stop
than in 1973.
Nonmetallic and metalic linings Abex's research for a high-performance, asbestos-
free brake lining material covered nonmetallic and metallic materials.
As tractorltrailers became more aerodynamic, reduced drag caused brakes to work harder; increasing wear and operating temperatures. Trucks like this Mack Ultra-Liner demand more brake horsepower than less "slippery" trucks of 10 years ago.
SCI 03109