Viton tubing is prized primarily because of its resistance to petrochemicals, particularly diesel and other fuel varieties. For this reason, Viton performs very well and is frequently used in engine fuel line systems. Unlike natural rubber tubing, which can degrade when brought into contact with petrochemical products in sufficient quantities, Viton retains its integrity when exposed to petrochemical products.
Viton is engineered to perform well at high temperatures; it can function without signs of degradation at temperatures as high as 200° C. It is also resistant to many oils, lubricants and mineral acids as well as exposure to ozone. Despite these qualities of high performance, Viton is not without its defects as an elastomeric utility. Viton's low temperature performance is very poor; when exposed to low enough temperatures for long enough periods of time, Viton can become cracked, which in fuel lines poses an extremely dangerous hazard.
Viton is an example of black rubber tubing, most varieties of which are applied in industrial processes or in other situations in which the tubing will be exposed to harsh conditions. One common method of Viton tubing manufacture is extrusion. The extrusion process involves forcing a raw material through a die in order to shape it into a usable product. In Viton extrusion, the process begins with a collection of raw Viton in a hopper suspended above a conveyance channel. When the Viton is released into the conveyance channel, a long shearing screw forces the Viton down the channel as it turns.
The friction and pressurization caused by the turning of the screw causes the Viton to become molten. Once molten, the Viton is ready to be forced through the extrusion die at the end of the conveyance channel. A die, in the case of extrusion, is a specially shaped hole in a metal plate that gives a material its shape. When molten Viton is forced through an extrusion die, it takes its shape and emerges on the other side of the die as newly extruded Viton tubing. The tubing can then be cut to length and prepared for shipment to customers or for additional processing if necessary.