PLASTIC FUEL LINES AND STATIC ELECTRICITY
We all agree that fuel and static electricity can be pretty scary. Static electricity is a kind of electric charge that stays in one place- it is static after all. It is the opposite of current electricity which moves from one place to another along a defined path in a circuit.
Static generally builds up when insulators or insulated conductors are rubbed. In order to get rid of static electricity, we have to turn it into current electricity by creating a circuit. That’s what happens during a lightning strike: so much electric charge builds up in a cloud that the air between the cloud and the ground no longer acts as an insulator. And while anyone playing the best round of golf in their life probably won’t admit this, lightning can be pretty scary. So can static discharges in automotive applications. A spark near something explosive and you have a fireball on your hands. We all know the damaging and costly effects of handling delicate electronics after walking through carpet. This is where anti-static products such as conductive hose are required as explained below.
There are two ways we can prevent static build up in a hose: by physical methods or by chemical means. For hoses, this can mean a highly conductive wire is run through them, or, more commonly, through the addition of additives to the tube liner that helps conduct and dissipate static charge. The latter is the approach Racetronix takes with its TFT1170-series Teflon™ hose.
It is important to know why static is particularly problematic with plastics such as Teflon. The conductivity of Teflon is exponentially lower than silicone and even rubber and this is why we don’t see the same anti-static emphasis on silicone and rubber hoses. The antistatic hose offered by Racetronix is essential in applications where media passing through the hose has a low conductance. Especially problematic are fuels, solvents and Freon. It’s important to note that anti-static liners not only prevent things from going “BOOM!”, but also help extend the life of a hose. In applications using fluids with low conductivity and high velocity, a static charge is quickly build up in a non-conductive hose. This charge then tries to “move” to ground by arcing from the inside liner out to the wire braid. This leads to tiny pinholes in general purpose Teflon hose liners. Late-model factory fuel systems use a combination of conductive plastics and grounding wires in the tank and pump modules to dissipate static electricity. Automotive performance applications can greatly benefit from the use of conductive anti-static liners. The marginally higher hose cost is quickly offset by longer life and improved safety.
In conclusion, when choosing a hose for a new application it is important to consider not only the flow and chemical compatibility of potential hoses, but also the electrical properties. With high flow, low conductivity fluids, please consider Racetronix TFT1170-series conductive lined Teflon braided hoses.