Zetex (fabric)

Zetex fabrics were invented by Bal Dixit in 1978. This highly texturized fiberglass fabric exhibits many of the same properties as asbestos, such as resistance to heat, corrosion and rot resistance, outstanding electrical properties, ability to withstand moltenmetal, and thermal insulation. However, it does not carry the same health risks.[1]

Testing

Zetex has been tested against asbestos to prove it is a good replacement. Two Zetex filaments were created, one with a 9 um diameter (G) and a 6 um diameter (DE).

Physical Properties

Chrysotile, the most commonly encountered form of asbestos, has a density of 40 oz/yd2, while Zetex G has a density of 35 oz/yd2, and Zetex DE has a density of 32 oz/yd2. Other physical properties are listed in the table below:

Table 1 - Comparison of properties of asbestos and texturized fiberglass (Zetex)
Property Asbestos (Chrysotile) Zetex G Filament Zetex DE Filament
Density (oz/yd2) 40 35 32
Breaking Strength, lb (Warp/Fill) 160/80 346/423 442/428
Abrasion Testing

(cycles to failure - CS10 Wheel, 500 g/wheel)

230 to 824 493a 871
Thermal Properties

"K" value, Btu/h/in./ft2/°F

.8190 .3385 .3399

a CS17 Wheel, 1000 g/wheel

Temperature Rise Testing

A glove was fabricated from this material to allow for further testing to be done. A thermocouple was used to test the inside temperature of the glove while holding a 600°F(316°C) pipe. A measure was taken to see how long it took the inside to reach 140°F. Both gloves included the same wool liner. Another test was done with a 1200°F(649°C) pipe.

Table 2 - Rise in Glove Temperature (in F) with a 600°F pipe
Time (s) Zetex Asbestos
0 77 77
5 86 86
10 89 95
15 99 112
20 112 123
25 123 131
30 133 136
35 140 142
Table 3 - Rise in Glove Temperature (in F) with a 1200°F pipe
Time (s) Zetex Asbestos
0 80 80
5 85 105
10 92 135
15 110 ...
20 135 ...
25 ... ...
30 ... ...
35 ... ...

Uses

Zetex can be used for a variety of fire protection applications.

Entertainment/Theatres

Zetex has replaced asbestos as the material for the large fire curtains that lower and close off the stage opening in case of a fire in a proscenium type theatre or auditorium.

Construction

During welding, workers can wear Zetex-made fire suits for protection. Also, Zetex material can be used for fabric expansion joints, creating fire barriers in buildings.

Automotive

Zetex material can encapsulate gas tanks or exhaust pipes, protecting from fire caused by gas leaks.

Foundries/Welding

Zetex suits can be used in welding applications, protecting the worker from sparks and other molten objects. It can also be used to create a fire barrier.

Fire Safety

Fire departments can use Zetex made suits to battle fires due to Zetex's heat resistant properties. Full engulfment capabilities of the suit make for a good emergency combatant.

Glassblowing

When boxing a newly finished piece of glass for annealing a Glassblower may utilize Zetex gloves to hold the finished piece in transition from the knock off table to the annealer.

References

  1. Dixit, B., "Performance of Protective Clothing: Development and Testing of Asbestos Substitutes," Performance of Protective Clothing. ASTM STP 900, R. L. Barker and G. C. Coletta, Eds., American Society for Testing and Materials, Philadelphia, 1986, pp. 445-460

External links

This article is issued from Wikipedia - version of the 9/13/2016. The text is available under the Creative Commons Attribution/Share Alike but additional terms may apply for the media files.