Potential commercial DC design question

[Bill White]

I hope to begin a consulting job with a commercial WWing shop (pretty large) in the immediate future.
One main concern if duct/chip collection. There is NONE at present.
Can anyone suggest a company that will design and supply adequate systems for a commercial environment? This job would be WAY over my small shop experience.
PM if ya feel that it would be more appropriate.
Bill

[Michael W. Clark]

Bill,
I sent you a PM, and would be happy to discuss your application. If you have any specific questions you want to discuss publicly, I'll be glad to help any way I can here as well.

Mike

[Jim Andrew]

Wish I could remember the name of the company that did the shop where I worked. They put in a huge dust system, something like 15 hp, and then ran 4" to the machines. Incl the timesaver thickness sander. 37" wide. Beware, there are idiots out there!

[Rick Fisher]

http://www2.donaldson.com/torit/en-u...ollectors.aspx

http://www.belfab.net/en/index.html


If your in the south, temperature isn't probably as big a deal as Canada .. Belfab and Torit are rugged and reasonably priced.. In Canada, they need to be outside now, due to microscopic particles. There seems to be a move towards the larger Felders or AL-KO collectors which offer Hepa .. I have seen lots of Felder style ..

The AL-KO is in my opinion a sweet unit but big $$$ .. I think they are sold by Martin in the USA ..

[ian maybury]

Think the big attraction of the Felder type units Bill (and there's lots of other makers of similar style packaged dust collection and filtration units in Germany - at varying price points and with varying specs (levels of sound proofing etc) may be that for requirements of up to a certain CFM/number of machines they deliver a packaged piece of equipment that can be wheeled in and hooked up with flex hoses (no need for ducting/building mods) that guarantees to deliver return air to a defined quality standard.

Which may remove some of the risk with custom built to order systems - although it still leaves stuff like machine hooding arrangements etc very much in the mix.

One caution about these is the possible cost (surmising here as i've not used one) of keeping clean filters in them - they don't seem to have anything by way of a cyclone to drop dust out before the filters, and a filter change is quite a big job. Filters may not be cheap. They seem to suit smaller applications running one or maybe two machines at a time - where it suits to recirculate the air. As in say a location within a larger factory doing mostly something else, or a smaller shop as opposed to a large woodworking business.

It seems likely that a larger scale system requires custom design and installation, which brings into play the matter of competence and proven ability to deliver a system meeting the required air quality and other standards.

Stuff like use of high efficiency cyclone(s) and filtration, optimisation of machine hooding, provision for future expansion, and the possibility of exhausting outside/into a silo to enable easy emptying, noise, electrical/other technical standards, required services, waste handling, compaction/briquetting, integration with heating/cooling systems etc etc could be a big part of this. Also running costs and/or energy consumption, ability to perform and remain efficient with only a few or with many machines running (turndown), ease of operation and maintenance. Not to mention practicalities like system layout and space requirement. It's not just about capital cost.

This means that any serious supplier really needs to commit to meeting clearly defined set very widely differing requirements in lots of different areas, and to know their stuff.

Not sure about in the US, but over here many potential suppliers (i've spoken to a few and been disappointed - size is no indicator of sophisticated expertise) are basically sheet metal bashers/parts sellers and are very weak on technicalities and not just mech but also air engineering. They tend to be led by fairly archaic 'that's the way we always did it' and rule of thumb thinking (which has always been based on skimping - on doing the minimum at least cost necessary to get by), and to not be up to speed on the regulatory side of things.

The need to meet tough requirements set by various regulatory bodies - e.g. seriously demanding workplace air quality standards like the 1 - 5mg/m3 TLV requirement - is a pretty recent development, and quite a few of these companies don't seem yet to have come to terms with it.

The well established likes of Camfil Farr, Donaldson Torit and so on seem to have lots of expertise on high efficiency dust collection and air cleaning, and to have done quite a lot of research into the issues over many years. (their websites are worth ploughing through - they tend to publish lots of useful papers on a variety of topics) They no doubt don't come cheap, and their solutions will lock you into using their consumables - but the other end of the scale as above is unlikely to suit. Maybe there's a middle ground if the right company can be found....

Turnkey design/build/install/commission i.e. A-Z responsibility may make sense. Splitting design and build responsibilities may seem attractive, but could make accountability difficult.

My instincts would be to first spend some time working to establish the regulatory picture, the state of the art and its capability, and gaining a fairly clear view on the needs and on how they may be delivered - with a view to writing a requirements and performance specification.

Maybe talk to a number of specialists first to get some help with this. (ideally independent expert types, not suppliers - the latter will just recommend what they can supply) Then talk to potential suppliers at the level of requirements, but without specifying technicalities. (even though you may have ideas on solutions) Let them propose them. That way you maximise the input you receive, and don't dilute responsibility.

Just the thoughts that come to mind, your reality may prove to be different...

ian

[Michael W. Clark]

Ian makes some very good points. Depending on your situation, spending the money to get the system engineered may be the best way to go. However, one thing to be aware of is the increased attention from OSHA regarding NFPA. Large wood processing facilities have to take this into account with their collection equipment. Small cabinet shops are also subject to it, but it may be best to have multiple smaller systems to minimize the requirements. Regardless, all the ductwork will have to be conductive with less than 1M-ohm resistance and minimum conveying conveying velocity met at all times in branches that are being used.

It is difficult to go much beyond that without knowing the specifics. The design for a 5,000 CFM system is much different than the design of a 50,000 CFM system.

Mike

[Bill White]

Thanks all. Good info. Hope to get this going soon.
Bill