Donaldson Torit UMA250 or Felder RL250?

[Albert Lee]

I have given up on upgrading my existing dust extractor, I will sell it and upgrade to a new dusty.

I can not decide if I should go for a Donald Torit UMA 250 or a Felder RL250.

They are both 5.5kw, UMA 250 has filter area of 244 sqft, Felder has filter area of 538 sqft.

For a UMA250, there is no need for a compressor, it has its own auto shaker motor to shake off the dust when switched off, has its own explosion relief panel (no need to hook up sprinkler), can place outside the shed in the weather, placing the extractor outside is my ultimate goal and its probably the best practice... my neighbour wont mind as I am in a semi rural area, I like the auto shaker and no need to hook up sprinkler.

Here is the fan curve of the UMA 250, G8 fan is 5.5kw.

289672

For a Felder RL250, it needs to hookup to a compressor (not a big deal I've got a 7.5kw hydrovane compressor but then I will need a dryer which is another cost), the Felder is designed to be used in door - occupy valuable shop space, my workshop is only 600 sqft.

The price for a RL250 here is $16k USD after tax. and a UMA 250 is $14k USD.

What does my fellow SMcreekers recommend?

[Jeff Duncan]

So if I'm reading correctly one system will do everything you want and cost $2k less than the other system which will not do everything you want? Soooooo what's the question again?

JeffD

[Albert Lee]

Hi Jeff I guess the question is that does the Felders extra filter area worth the 2k?

Also the Unimaster has an explosion relief panel, Donaldson Torit strongly recommends the unit to be placed outside, because if there is an explosion, the positive pressure may cause damage to my workshop. Probably a good thing but it just meant extra funding required for all the wiring, ducting and builder work to the house.

[Rick Fisher]

I live in Canada and would probably buy an ALKO 250 as a first choice. The big advantage for a Canadian to an indoor unit is heating. How cold is it in your area ? Or hot ?

Paying to heat or cool a shop and then removing 3000 cubic feet of air per minute is frustrating for someone in a 600sf shop.

http://tfzje.zqejf.servertrust.com/ProductDetails.asp?ProductCode=AL-KO-Power-Unit-250-P

Bit more money, bit bigger motor. 250mm intake. Quieter and hepa.. Runs inside ..

[Albert Lee]

I live in Canada and would probably buy an ALKO 250 as a first choice. The big advantage for a Canadian to an indoor unit is heating. How cold is it in your area ? Or hot ?

Paying to heat or cool a shop and then removing 3000 cubic feet of air per minute is frustrating for someone in a 600sf shop.

http://tfzje.zqejf.servertrust.com/ProductDetails.asp?ProductCode=AL-KO-Power-Unit-250-P

Bit more money, bit bigger motor. 250mm intake. Quieter and hepa.. Runs inside ..

hi Rick, thanks for that, I have come across al-ko while searching the dust extractor, but they are not available in New Zealand, big money there are, probably the best on the market...

temperature wise , annual average is 64 Fahrenheit, 32 would be very cold days probably 2-3 days a year at its coldest time of the day(during daytime it will be 40), hottest would not be over 80.

[Justin Ludwig]

I"m curious as to what application either of these units would be used for in such a small space? At first glance, by an ignorant eye (mine), it seems overkill.

[Albert Lee]

hi Justin, I have a 37 wide belt sander, a combination machine that comes with 16" planer, a chisel mortiser that cuts long rectangular mortise (doesnt need a lot of suck) I am running a small production from my small workshop.

wanted the upgrade because I am frustrated with my existing extractor, its a high volume low pressure baghouse unit, when the pressure loss is high, ie restrictions, the volumn drops significantly.

[Jeff Duncan]

Hi Jeff I guess the question is that does the Felders extra filter area worth the 2k?

Also the Unimaster has an explosion relief panel, Donaldson Torit strongly recommends the unit to be placed outside, because if there is an explosion, the positive pressure may cause damage to my workshop. Probably a good thing but it just meant extra funding required for all the wiring, ducting and builder work to the house.

Well you mention having it outside as your "ultimate goal", so I would't count those extra costs against the Torit as they've be the same for either unit. And if that's your goal, which by the way I agree with, then those costs are a moot point. Now if your collector is outside and your climate allows for it I would leave the filters outside as well. If you can do that then you don't have to worry about the extra filter area of the Felder. Though if we're going to look at it practically, if you could leave it outside you wouldn't need to spend anywhere that kind of money for either of these units! A much simpler unit would do just as well. If however you do need the air to return, then maybe the filter area becomes an issue. However, I would be more concerned with which unit filters better, than which filters more. IOW which will provide the cleanest air return. Then you can decide if there is a real difference and how much that difference is worth monetarily.

good luck,
JeffD

[David Kumm]

Albert, in that mild climate is exhausting outside a possibility? You are talking about commercial size units for commercial sized shops that must recirculate the air. A cyclone located outside would exhaust almost clean air directly and could be bypassed back into the shop with cartridges in extreme weather. The WB wouldn't rely much on the cartridges and the whole thing would be way less than half the cost. Dave

[Albert Lee]

hi David, I am reluctant to exhaust outside, Donaldson Torit local rep commented the fine dust generated by timber is not permitted by council, and to comply I may need to submit a resource consent which will cost thousands of dollars.

thats why I am inclined to the filter bag unit.

I probably endup where I started, an indoor Dantherm/Nederman S series unit, 2nd hand cost about half of new.

[Michael W. Clark]

Albert, is replacing the fan on your existing unit an option?

[Albert Lee]

Well you mention having it outside as your "ultimate goal", so I would't count those extra costs against the Torit as they've be the same for either unit. And if that's your goal, which by the way I agree with, then those costs are a moot point. Now if your collector is outside and your climate allows for it I would leave the filters outside as well. If you can do that then you don't have to worry about the extra filter area of the Felder. Though if we're going to look at it practically, if you could leave it outside you wouldn't need to spend anywhere that kind of money for either of these units! A much simpler unit would do just as well. If however you do need the air to return, then maybe the filter area becomes an issue. However, I would be more concerned with which unit filters better, than which filters more. IOW which will provide the cleanest air return. Then you can decide if there is a real difference and how much that difference is worth monetarily.

good luck,
JeffD

Well Jeff Although it's ultimate goal one of the aim is they need to be quiet, not sure if the cheaper units are quieter? Need to research on this. If they are louder outdoor which may upset he neighbour then I may still have to place it inside.

[Albert Lee]

Albert, is replacing the fan on your existing unit an option?

am researching this too, it seems the setup is adequate just the impeller needs to be replaced to a reverse inclined impeller rather than the existing radial impeller.

[David Kumm]

am researching this too, it seems the setup is adequate just the impeller needs to be replaced to a reverse inclined impeller rather than the existing radial impeller.

Albert, are you talking about the unit with the slow rpm motor? The radial fan will deliver more cfm at pressure than a curved but not at that speed. Neither will unless run faster. The system you showed us before with a 2800 rpm motor will work well. Dave

[Albert Lee]

Hi David yes thats the one I am talking about.
We are not very industrious here, I have a few options

1. Replace the motor, use existing impeller.
a local motor specialist commented to have that impeller moving at close to 3000RPM I need a much bigger motor, everything on a bigger motor is different to a 4kw, therefore modification is required to the motor and the mount, which all cost $$$, it will quickly spiral into thousands of dollars, I dont mind to spend the money but what if it doesnt work at the end of it?

2. Use existing motor, replace the impeller
will have to import a reverse inclined impeller, possibly from US, Australia may have them, again, it may not work.

3. leave as is, onsell it.
There is nothing wrong with my extractor just not suitable for my application.
I've bought my extractor + 40' of 6" + 20' 8" spiral ducting + bends for under $1000 USD, knowing the market here it is likely I can sell them for a profit

[Michael W. Clark]

You may be money and time ahead to replace the motor and fan, then sell or 're-purpose the one that is on there now.

[Tim Campbell]

Albert,

A few things you could consider before you set off spending some big $$'s which may not even solve your problem.

With a 20" fan sucking through 10" ducting, I'd guess that the restriction in your system is the ports on your machines. Can these be upgraded to let your extractor reach its potential?

For about $150 you can hire a hot wire anemometer for the weekend from Tech Rentals in Penrose and carry out some meaningful measurements. You could measure cfm of your fan only, fan plus ducting and fan plus ducting plus machine and find out what's really going on.

Regarding the comments from the rep about council rules. He's trying to sell you his machine and may be selective with the truth. A good cyclone venting directly outside will release no more dust into the environment than any other weekend warrior using a traditional bagged dust extractor. Also when you drive around any industrial area in town you will see dozens of cyclones on the outside of factories. My understanding is that industrial H&S regulations ban extractors from inside the work environment.

If you do get a new motor to get the fan running at 2850 RPM, it would not necessarily need to be larger than your current 4 kW. Remember power consumption is primarily a function of the amount of air moved. If you are doing testing, a cheap clamp ammeter will tell you the current draw at various airflows which will enable you to get an understanding to whether the motor needs upgrading in size.

Hope that this al makes sense.

[David Kumm]

Albert, I don't remember if the fan has a taper lock bushing or just attaches to the motor shaft with a set screw? If taper lock you can swap that out with the motor. Once you know what cfm you want at a certain SP you can size the motor appropriately. There are no unique impeller designs. Going to a curved blade will quiet things down and may deliver more cfm at lower pressure than your radial but the radial will outperform under pressure if you have the kw. The pipe must be sized correctly- smaller diameter than 10" for sure. I don't know the prices of your alternatives but I'd put a 7.5 ( or 10 hp if you are nervous )motor on that impeller if it can accept the shaft. Really depends on the numbers of new vs rehab. Dave

PS I found the other thread and see I said this all before. Couldn't tell from the picture how the impeller is attached but if you can match the motor and speed you will have a top notch system. That is a nice unit.

[Albert Lee]

Hi David.

I am researching what other manufacture spec for their motor if its a 20" radial impeller.

I know I can modify it to make it work and it will probably outperform others if I have the KW right, but I worry it wont work and then its wasted time and money.

I maybe worrying too much... have this tendency all my life.

[Albert Lee]

Albert,

A few things you could consider before you set off spending some big $$'s which may not even solve your problem.

With a 20" fan sucking through 10" ducting, I'd guess that the restriction in your system is the ports on your machines. Can these be upgraded to let your extractor reach its potential?

For about $150 you can hire a hot wire anemometer for the weekend from Tech Rentals in Penrose and carry out some meaningful measurements. You could measure cfm of your fan only, fan plus ducting and fan plus ducting plus machine and find out what's really going on.

Regarding the comments from the rep about council rules. He's trying to sell you his machine and may be selective with the truth. A good cyclone venting directly outside will release no more dust into the environment than any other weekend warrior using a traditional bagged dust extractor. Also when you drive around any industrial area in town you will see dozens of cyclones on the outside of factories. My understanding is that industrial H&S regulations ban extractors from inside the work environment.

If you do get a new motor to get the fan running at 2850 RPM, it would not necessarily need to be larger than your current 4 kW. Remember power consumption is primarily a function of the amount of air moved. If you are doing testing, a cheap clamp ammeter will tell you the current draw at various airflows which will enable you to get an understanding to whether the motor needs upgrading in size.

Hope that this al makes sense.


Hi Tim

Thanks for all of this, exactly what I needed. will go to tech rental at Penrose to get some real measurement, hope they open on the weekend, I have a feeling the air speed at the end of the 3x4" is only 10m/s

[Chris Parks]

Albert, here is the link we discussed on the phone. They have done a very thorough job documenting the installation and the sound reduction measures they took.

http://mastslav.weebly.com

[Michael W. Clark]

I think I found the post with a picture of your existing collector. Looks like the fan housing bolts to the inlet plenum for the collector. If you change the fan, you may need to do some metal work or make a transition to the inlet plenum. You would also need to support the new fan. Even if you had this done professionally, it should cost considerably less than a 14-16K new collector.

If you want to replace the motor, David and Tim gave good advice about measuring your existing flow and SP. If you can get the flow and SP with your current setup, this relationship will help you size the new motor. If you know the flow you want, you need to determine the SP required to pull it through the existing duct system. The SP increases with the square of the flow change.

Motor brake HP can then be calculated as follows:
BHP = CFM x SP x df / 6356 / fan eff. The df (density factor) will be approximately 1.0 and the fan effiiciency will be close to 0.5 for a radial blade fan. You can convert BHP to kW and round up. You may have to install an inlet blast gate to choke off some flow to keep the motor from tripping out if you go from 1400 to 2850 RPM.

Theoretically, if you double the motor speed (and therefore fan speed), you double the flow and the power requirement would go up by 8X (the cube) accordign to the fan laws. This is why you would want to use a gate at the inlet (or throttle with gates at the hoods). This would cause you to move up the curve and draw less HP. You run the rist of being on an unstable part of the curve (causing fan surge) but really can't comment on that until you take a few measurements.

Mike

[Albert Lee]

Ok the Alko dealer in Australia has responded to my email, they can do the PU250 with 4 machines automatic detection accessories for about $17k USD delivered, this is cheaper thank I expected. I will use my existing setup as is and upgrade either next year or the year after that.

[Albert Lee]

hi Mike. this is what the motor specialist told me as well, I may go down this path just to play with the existing fan setup if I have time.

I had a look at my building and realised I cant reallly put in an outdoor unit because the wall is a plaster wall and we have all sorts of issues with making an opening on a plaster exterior wall here, apparently the building sector here doesnt know how to build a plaster house properly back then and government didnt realise this is a problem at the time...

anyhow this is why I may still endup with an internal unit. so its either Alko PU250 or Felder RL250, will be doing the researching in the coming months.

[Rick Fisher]

Albert. Your at the top of the food chain with those two machines. In a small shop, I would be most concerned with the design of the ducting. I run a much smaller RL-160 in a much smaller shop and suffer from the machine running over current. I think its a combination of machine design and also having such short runs of pipe.

There is a sticker on my RL-160 that says not to run the machine with no ducting installed. One of my machines is basically 10 feet of 6" PVC with an elbow away from the machine. With the gate fully open I run 5% - 8% over the FLA on the motor.

The airflow however at that machine is outstanding. :)

I can only assume that even bigger Dust collectors are even more sensitive to this sort of thing. I doubt the RL-160 is the only machine with a problem, and doubt the AL-KO is any different..

Just food for thought ..


Having said that .. An RL-160 eliminates the need for an Air cleaner in the shop. The Hepa filter system is amazing..

[Chris Parks]

Rick, you are inferring that a single 6" duct is overloading the machine? If it were starving the machine your current draw would not exceed the manufacturers specs.