Anti-static drag chains on 18 wheelers

[Stephen Tashiro]

Do trailers of 18 wheelers still have chains that drag along the pavement to ground the trailer and discharge static electricity? I used to see trailers on the highways with such chains 30 years ago. I don't recall seeing them in recent years.

[Wayne Lomman]

Never seen it in Australia. Used to see straps on cars but from memory it was debunked. The only time I see it is earth straps for fuel or LPG tankers when loading or unloading. Cheers

[Dan Hunkele]

In the forklift industry there is a non-marking tire available which is a rubber tire without the lamp black added to make it black. It is a grey color. Lifts with these tires on them need a static strap or chain to reduce the static build up. Lifts with standard black tires do not have a problem.

[George Bokros]

I have not seen the chains on 18 wheelers in years. Must have been proven static was not an issue. I only saw them on trucks carrying flammables such as gasoline.

[Rich Riddle]

Living in Kentucky, I do see trucks dragging chains out in the country from time to time. But we aren't exactly modern here. I worked the midnight shift at a gas station when a college student. When loading or unloading a fuel truck tank, the initial step a driver performs is to earth (ground) his truck. The driver will attach a small uninsulated wire (about ten gauge) with alligator clips about the size of those on a battery charger from the tank to an earth ground. A filling station will have specific earth ground for this ground wire to attach from the truck tanks. A driver once stated fuel flowing through the pipes creates a static charge that will eventually cause a static buildup spark unless he grounded his tank. The couplings are made of brass to eliminate any sparks.

[Curt Harms]

Living in Kentucky, I do see trucks dragging chains out in the country from time to time. But we aren't exactly modern here. I worked the midnight shift at a gas station when a college student. When loading or unloading a fuel truck tank, the initial step a driver performs is to earth (ground) his truck. The driver will attach a small uninsulated wire (about ten gauge) with alligator clips about the size of those on a battery charger from the tank to an earth ground. A filling station will have specific earth ground for this ground wire to attach from the truck tanks. A driver once stated fuel flowing through the pipes creates a static charge that will eventually cause a static buildup spark unless he grounded his tank. The couplings are made of brass to eliminate any sparks.

Aircraft refueling tankers have cables wound onto spring loaded reels with a clamp on one end. Step one is always to connect the ground. This is only found on jet fuel tankers though, I don't recall having seen them on Avgas trucks. Jet fuel is very similar to diesel but I think it may have a lower gel temperature.

[Rich Engelhardt]

They seem to have gone the way of the cab-over...

[Clint Baxter]

When I worked on vehicles that carried explosive components while in the Air Force, we used to have to check the grounding "strap" installed on them. It was a rubberized strap that was designed to discharge any buildup of static electricity that might occur while the vehicle was in transit.

The operators of the the vehicles also would connect a grounding cable to an established ground point, (we used to test these as well), prior to performing any actions on/with the components being carried.

All in the name of safety. An 80,000 lb solid fuel missile is not something you want any loose sparks around.

I dont remember seeing chains being drug, but saw the grounding straps on many a fuel tank truck/trailer. I would be more concerned that a chain could spark being drug over rocks and pavement.

Clint

[Myk Rian]

Years ago a trucker had a chain hanging off the back of his car carrier. Said it was there so people would talk to him on the CB radio.

[Lee Schierer]

Years ago (1968) my girlfriend owned a Oldsmobile with vinyl seats. She was forever getting zapped by static getting in or out of the car. We bolted a conductive rubber strip to the frame that would touch the ground when the car was stopped. That ended the static discharges.

[Malcolm Schweizer]

Aircraft refueling tankers have cables wound onto spring loaded reels with a clamp on one end. Step one is always to connect the ground. This is only found on jet fuel tankers though, I don't recall having seen them on Avgas trucks. Jet fuel is very similar to diesel but I think it may have a lower gel temperature.

I watched a guy touch a 727 before it was grounded. You have to ground the aircraft whether or not fueling, although definitely when fueling. This guy was new. The plane just landed, and he rushed to unload the bellies as we yelled at him to stop. It knocked him on the ground and he cried like a girl.

[David Freed]

I have driven 4 million miles in a semi. I don't remember them on trucks, other than gas tankers grounding when unloading, but have seen them on cars in the past.