Thread: explosion concerns!

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okay I have just read a thread about paint explosions.... and the messages given are very mixed... I have attached pictures of my enclosure I plan on painting in... my plans are to have the compressor, and fans run off of a generator .. and the lights and fresh air hood off of the houses power via an extension cord(s). the only things inside the enclosure would be the lights and fans blowing out...(2 box fans) ... I plan on having the fans blowing out with filters on the inside... then if you look at the pictures the enclosure has a vent at the top on both the front door and back door... I just want some honest opions on what the chances are of this atucally going BOOM!!!!! by the way the enclosure is 12x20x8



thanks,
simon

Not likely but not impossible. The box fans could be an ignition point.

All good fires need three things. Air,Fuel and ignition. Cut out any one and it won't happen. Air and Fuel can't be removed from the equation so you have to work with ignition. Have the box fans blowing filtered air in instead of loaded air out. Another thing most people miss is grounding the chassis or whatever is being painted. Static can make quite a spark. Other than that, you should be good to go.

I personally don't see how an induction motor can spark a fire...

A brush motor, yes.. but your typical AC motor is pure induction.. no sparks involved..

But I suppose that spark proof motors are fully enclosed so there must be something to it..

anyone wish to eludicate me?

It's that ol black magic. Guess I wasn't clear. The fan thrashing around in air that is loaded with vapors and paint dust will generate a ton of static. A static spark is just as good a source of ignition as a match in these conditions. If having the fans on the out side is a must, you might want to consider squirrel cage fans. They use centrifugal force to pump air rather than thrashing the air with a screw to make it move. Cages are relatively static free.

I don't think I've ever heard of fan blades causing static. Not saying it's not possible, just haven't heard of it before. I have a DeVilbis sealed fan that's suppose to be explosion proof, but it still has fan blades spinning in the soup.

more likely to get a spark from the switch than the motor... turning on or off is when you get in trouble

-Chris

Most single phase AC motors use a capacitor to aid in starting. There is a relay/switch internal which can arc for sure. Seen it many times. Just don't start the fans with a lot of fuel-air mixture around them and you should be OK.

Kitz

.........and don't use a torch to light your cigarette while laying down the clear coat.