industrial wood shop DC
industrial wood shop DC
(OP)
As an amateur woodworker on the side, I was pleased when my next work assignment was to design a dust collection system for an industrial wood shop (Maybe this will inspire me to move beyond the shop vac in my garage). However, since I am new to the HVAC design world, I've got a few questions.
Apparently this will be a basic woodworking shop. No finishing, just multiple BS, DP, TS(3), RAS, and a surface planer.
My basic idea is a cyclone separator for the big stuff followed by a cartridge-type DC. Obviously the fan should be sized for all equipment operating at once. However, instead of a mega-sized constant speed blower, are variable-speed devices used?
I'm envisioning a flow or pressure measuring device linked to a variable speed drive on the fan. Airflow would vary based on demand. Automatic blast gates on individual equipment would open when the equipment is started and vice versa.
Does anybody have experience with similar systems or is it easier just to keep the basic CV system?
I would also expect that the DC equipment would be located outside and fresh air make-up would be required to cover the exhaust stream(independent of the conditioned air). Is this right?
TIA.
Apparently this will be a basic woodworking shop. No finishing, just multiple BS, DP, TS(3), RAS, and a surface planer.
My basic idea is a cyclone separator for the big stuff followed by a cartridge-type DC. Obviously the fan should be sized for all equipment operating at once. However, instead of a mega-sized constant speed blower, are variable-speed devices used?
I'm envisioning a flow or pressure measuring device linked to a variable speed drive on the fan. Airflow would vary based on demand. Automatic blast gates on individual equipment would open when the equipment is started and vice versa.
Does anybody have experience with similar systems or is it easier just to keep the basic CV system?
I would also expect that the DC equipment would be located outside and fresh air make-up would be required to cover the exhaust stream(independent of the conditioned air). Is this right?
TIA.





RE: industrial wood shop DC
use the industrial hygenists handbook
you have to keep the air velocity high enough so you convey it into the collector
4000 fpm seems to ring a bell (dry dust)
you should be at 12" on the fan
i use torit mfr in the past, with "sock" after-filters and silencer, check codes for recirc restrictions due to combustible wood dust, its been some time since i eng one
there are mfr's for high pressure flex hose used where needed at the equipment, i dont have the url handy
RE: industrial wood shop DC
Thanks for the help.
RE: industrial wood shop DC
RE: industrial wood shop DC
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Intalling multiple DCs is a better idea than going for vfd control. I strongly opine that a switch is a better energy saving device.
As wood dust is in the infinite list of carcinogens, you may rethink about your option of recirculation. Anyhow, you can use enthalpy wheels or runaround loops to tap the energy.
Regards,
RE: industrial wood shop DC
I have a technical handbook from N.R.Murphy, which gives recommended extraction numbers for equipment as well as recommended duct velocities for conveying sawdust, chips, wet or dry.
I recommend checking out there website and ordering the manual (it was free).
http://nrmurphy.com/
My two cents is that constant volume systems are easiest to control, and maintaining duct velocity (3800-4200 fpm for sawdust) is almost impossible with a VFD.
We tend to specify the combination cyclone/filtration unit. With a terylene filter.
Other concerns are fire protection related. Check your local codes if a sprinkler protection of the unit is required. Fan should be AMCA class A.
RE: industrial wood shop DC
You can probably size the unit for some diversity. 70% of the machines operating then isolating the additional extraction runs with blast gates.
RE: industrial wood shop DC
RE: industrial wood shop DC
RE: industrial wood shop DC
RE: industrial wood shop DC
I doubt you could cavitate duct at pressures seen in a typical woodworking system since the duct will have to be strong enough to take the occasional wood-block careening through the system anyway. Blocking off all the inlets is probably undesirable jsut form the noise standpoint but it does get pretty efficient that way with lower motor amps pulled.
Oneida seems to know what they are talking about and appear to have reasonable prices.
A varibale-pitch drive might be nice to allow a balancing of the system without multiple sheave and belt changes. This limits you to lower HP systems.
An initial flow measurement is handly to ensure you're at a minimum conveying velocity. Too high jsut wastes energy, too low... well. This can be done with a $50 Grainger magnehelic and a pitot tube. Reuse the magnehelic on your afterfilter to indicate when it needs to be cleaned.
RE: industrial wood shop DC