Extractor fan

[sparky_col]

Hello
I am intending spraying 2k in my workshop and need to install some kind of extraction system the area where i will be spraying is about 14' wide by 20' long the ceiling height is about 10', would a 24" axial fan set into one of the walls be sufficient? my workshop is attached to my house so i want to be sure of good extraction. i have been looking at the clarke fans, they are expensive, is there an alternative?
thanks for any help
Col.

 

[brightspark]

Hello
I am intending spraying 2k in my workshop and need to install some kind of extraction system the area where i will be spraying is about 14' wide by 20' long the ceiling height is about 10', would a 24" axial fan set into one of the walls be sufficient? my workshop is attached to my house so i want to be sure of good extraction. i have been looking at the clarke fans, they are expensive, is there an alternative?
thanks for any help
Col.

that will shift a lot of air the only problem is u would need to use a filter to stop dust getting sucked in to garage when the fan extracts out. it will also pull in cold air if the temperature is cold outside

 

[the snooper]

just though i would post this info i found it may be of use to someone

How do you calculate spray booth airflow?
A properly designed and operating spray booth in a finishing facility is a major ingredient in the achievement of the finish required by the manufacturer. Either of following two methods can analyze the proper airflow:
Air Velocity (Feet per Minute – FPM)
Air Volume (Cubic feet per Minute – CFM)
Prior to 1995, the National Fire Protection Assn. (NFPA) book 33 listed the proper flow for spray booths using non-electrostatic spray equipment at 100 FPM. That was determined to be adequate flow for the protection of the operator. Current regulations stipulate the proper flow is:
The air volume required to dilute solvent concentration below 25% of lower flammable limit (lfm).
This can either be calculated using all the booth parameters, paint flow, paint characteristics and spray gun efficiency, or purchase test equipment which is designed for specific solvents. Most facilities do not have the equipment or expertise to determine the solvent concentration in the booth and still rely on the 100 FPM guideline.
To calculate the amount of exhaust air needed for the booth, a simple calculation is used.
CFM = Booth Face Area in square feet multiplied by the required flow (typically 100 FPM)
For example, and 8 X 10 filter bank (80 square feet) would require an exhaust of 8000 CFM (100 X 80) to achieve the required 100 FPM velocity.
To calculate the existing velocity knowing the exhaust volume the following formula is used:
Velocity = Exhaust in CFM divided by the booth filter area.
For example, a fan that exhausts 9000 CFM with a 10 X 10-filter bank would have a velocity of 90 FPM.
Proper airflow is not only necessary for the protection of the operator, but is necessary to achieve the desired finish quality. Flow that is too low will not draw the overspray to the filters. Much of the overspray will end up on the part as dry spray (rough finish). If the flow is too high, solvent tend to evaporate too quickly resulting in dry spray.

 

[sparky_col]

that will shift a lot of air the only problem is u would need to use a filter to stop dust getting sucked in to garage when the fan extracts out. it will also pull in cold air if the temperature is cold outside

Thanks for your reply
i am just in the setting up stage at the moment, I have 2, 15cfm single phase compressors in a seperate room attatched to my workshop, they are in a closed space with no ventilation as yet, i am thinking this, if i have a inlet from the compressor room to the outside and then a outlet into the area where i am going to spray and then an extractor in the spray area, then the spray area extractor will pull air through the room with the compressors in, this air will be cold into the compressor room which will be good for them, they will then warm it up when it is drawn into the spraying area and if i filter it at the point where its drawn into the spraying area every thing should be kosha..
does this sound ok?
thanks again for any advice.
regarding filters, where can i look for these?
cheers
Col

 

[the snooper]

spray booth filter usually comes on a big roll
but as posted above spraybooth ventilation uses a massive cfm so it may be worth doing some calculations to see if you will be wasting your time and money with the fan you intened to buy

 

[sparky_col]

spray booth filter usually comes on a big roll
but as posted above spraybooth ventilation uses a massive cfm so it may be worth doing some calculations to see if you will be wasting your time and money with the fan you intened to buy

Thanks Snooper
it will take me a little time to re- read your information and do the calcs will update my post when i have done so.
Cheers
Col.

 

[marc.w]

Sorry to hijack this thread, though the answer may be pertinent to the original poster too....

I've been thinking about building my own open fronted spray booth and have read that an explosion/flame proof fan is needed. Is this absolutely needed? I will only be spraying 2k clear, is it that combustible?

 

[brightspark]

Sorry to hijack this thread, though the answer may be pertinent to the original poster too....

I've been thinking about building my own open fronted spray booth and have read that an explosion/flame proof fan is needed. Is this absolutely needed? I will only be spraying 2k clear, is it that combustible?

in an industrial enviroment the corect gear would be needed. as said flameproof fans and light fittings. a normal fan would be ok to use as long as the wire is in to the conection box on fan and a stuffing gland fitted and switched outside the booth