Sealed positive pressure case.

[Leggir]

I'm looking to build a completely sealed case for a friend that I'd like to positively pressure to 136 kPA as the environment it's working in extremely dusty. It's in a coal heated welding shop. So as you can imagine, there's fine coal dust, steel, aluminum, and other metals in the air which make short work of every filtration system I've tried. As an electrician that works in various industrial settings, we sometimes do use positively pressured junction boxes in areas where explosive gas or dust can get into sensitive electronics, however these are usually engineered and UL Listed.

 

Most recently I completely lined the CNC computer with twin layers of micro-filters, and while it reduced the amount of dust inside, when I went to clean them out the particulates had clogged the filters enough I had to use an air compressor at over 60 psi to get the filters clean. In so doing, it ripped the filters which I had expoxied into the case.

 

Purpose: CNC AutoCAD computer that does do basic 3D drawings, mostly engineered drawings that parts are extrapolated and cut on plasma or waterjet. Current Core2Duo works fine for this.

Build: i3-7100, 8GB DDR4, iGPU, Wireless Mouse and Keyboard

 

I wonder about the cooling. While the ambient temperature is around 20C, with no fresh air and no exhaust the only air moving has to be what's inside the case. I wonder if positive pressure may create havoc with fans?

 

 

[Electronics Wizardy]

3 minutes ago, Leggir said:

I'd like to positively pressure to 136 kPA

thats like 20psi. Something gonna go boom.

 

If you want a cheap pc that will do this, get a fanless industrail pc. Like this onehttp://www.advantech.com/products/ark-2000_series_embedded_box_pcs/ark-2121f/mod_eb8fd822-1cca-4006-8ac1-def225eb4f59

 

or this https://www.newegg.com/Product/Product.aspx?Item=N82E16856101152

[Leggir]

Actually its only 5 psi over ambient, seems how normal air pressure is 101.2 kPA or 14.5 PSI.

[Electronics Wizardy]

1 minute ago, Leggir said:

Actually its only 5 psi over ambient, seems how normal air pressure is 101.2 kPA or 14.5 PSI.

thats still a ton of pressure. Your gonna need a hefty blower for that. 

 

Why not get a premade fanless pc.

[Leggir]

For the industrial cabinets we've done, they just have an air valve like a tire, which you use to pressure. It's worth considering a fanless unit no doubt, that's why i'm looking for input. I was still thinking sealed because what inevitably happens is it gets neglected until it lets the smoke out in a "oh you mean we had to spray off the heatsink on the outside of the case" moment.

[Leggir]

That Ark looks good, I'll chat with them when they open.

[stconquest]

You could try a mineral oil system.  The main components could be 100% sealed in an enclosure.  It is really heavy though.

[Energycore]

I support the idea of grabbing a sealed fanless computer for this. Should be able to get one with dust-resistant certification too.

[brob]

I suspect a purpose designed pre-built unit makes the most sense. But another option might be to remove the system to a more amenable environment and remote the peripherals.