Central Dust Collector System Build

[cnc-me]

I'm not one to be using a screaming loud Shop Vac, so here is my
shop built Dust Collector .
Its a 5 H.P. 2 stage blower, mostly used for combustion air on large boilers
but works for pulling air as well.
Below is the main skid for the entire unit, made from 1/4 thick 2x2 square tube.
The tube was salvaged from another machine I tore apart.




My stick welds are looking better. (Not all of them are this nice )




Shot of the cast aluminum North American blower with 5HP 3 phase Westinghouse motor.


The framework on top is for a roof and will be covered with pole barn steel.
This unit will set outside on a concrete pad, with a 55 gal. drum as the main container for metal shavings & dust.


Bolts holding the filter cabinet in place.
Black circle is were the inlet air will be located.


The filter cabinet used to be an electrical cabinet.
Its a NEMA 12, so its air tight, and strong enough to resist the pull inwards
that the blower will develop.


Support bar for 3 cartridge air filters.


The dust deflector is the one-half of a Simplicity tractor blade.
You can see what I made out of the other half here.
http://www.garagejournal.com/forum/showthread.php?t=64925


More to come later...
-John

 

[A_Pmech]

I was just thinking about building a dust collector "barn" this evening.

Good timing!

 

[cnc-me]

I was just thinking about building a dust collector "barn" this evening.

Good timing!

This project is done and installed,
just don't feel like posting anymore of it tonight.

Can't believe I never took any pictures of it installed.
I will take some tomorrow...

 

[NUTTSGT]

This thing definetely heavy duty, did you move it with a fork lift ?

 

[kbs2244]

I will be intrested in how well you can vacum metal chips.
I see systems in wood shops all the time, but cannot recall one in a metal shop.

 

[cnc-me]

This thing definetely heavy duty, did you move it with a fork lift ?

It sits just outside the shop which is cement so I used a 3000# Hyster.
I would guess that it only weighs 700-800 pounds as the blower is all
cast aluminum.

 

[cnc-me]

The progress so far....
11

Here is the filter mount plate that goes inside the cabinet.
The 3 cartridge type air filters will set over the rings to help hold them in place.
Stainless steel bolts will be used to attach the plate to the cabinet, through the small flange around the perimeter.
Silicone will be used around the flange to seal it off, so the blower can only **** through the filters and no place else.
12

Another shot of the filter mount rings.
13

Air tank mount
14

Both tank mounts are complete, and await welding to the tank.
15

Checking tank alignment before welding on the mounts.
16

17

18

Aligning the 3 homemade fittings before welding.
3/4" pipe will screw into these fittings, to bring air to the top of each filter, to act as a back-purge or cleaner .
The filters are special units made to be cleaned, with compressed air in this fashion.
As you use this collector the filters will start to resist airflow as they fill up with all sorts of crud.
You put about 45 to 50 pounds of air in the tank, and expell the whole tank, to clean each filter one at a time.
Commercial units have all sorts of timers and electric valves for this to happen automatically.
I decided that I didn't need any of that, and went with 3 ball valves instead.
When my airflow starts to drop, I shut down the unit, turn on the main valve to the tank and let it fill, then
go outside and open each of the 3 filter valves one at a time, pausing to let the tank refill after each.
19

The "Never Weld On a Pressure Vessel Boys", will have a field day with this.
Shown here is one of the fittings welded to the old portable air tank.
Had one heck of time welding these things onto the tank, because my home made fittings
ended up being free machining or leaded steel.
No wonder why the turning and tapping jobs went so fast on the lathe.
Leaded steel is made for turning, not for welding!!!!
That will teach me to use an unmarked piece of steel from the junkbox.
Leaded steel is only available in round or hex stock, so you don't have to worry about any flat stock being leaded.
20

Tank, deflector plate and other small parts waiting to be sand blasted.
21

Door latch made from a single piece of 16 ga. x 1-1/2 square tube
The end was closed off, by cutting a V out of tube then folding it over, and welding
22

Here is the purge tank aloft on its new mounts.
23

Nordfab piping welded on to a custom adapter for the North American blower.
Nordfab piping is great stuff to work with, everything just clamps together .
Its quite expensive, but worth the extra cost if you want a first-rate system
thats easy to work on, and change in the future when needed.
24

Blower shown here with the outlet on top, I later turned it so that the outlet is out the other side and on the bottom.
Having the outlet on the bottom, will direct the exhaust air away from the side of the shop where the unit is mounted outside.
25

Purge tank all plumbed in with the 3 ball valves.
26

At the bottom of the cabinet, is a clean-out that I welded on, to remove all the dust inside the filter cabinet.
A 5 gallon bucket will fit right under the clean-out.
On the left side is the inlet.
Air passes through a 55 gallon drum to get rid of the bigger stuff first,
then on to the inlet through the filters and finally through the blower outlet.
27

Here you can see the "Perch" for the air tank to mount on.
Rubber machine mounts are used under the main framework,
to get the unit up out of any water that may be present.
All of the 1-1/2 square tube used in this project is made from Yamaha ATV crates.


Top of cabinet showing air piping, used to clean the filters.
Shown in the center is the outlet from the filters, before it heads to the blower.
Those pipe flanges are made from hole-saw slugs.
Each one has a rubber gasket under it to seal the air in and any rain water out.


30

At the extreme top you can see the holes for the steel roof frame to bolt on.


Inside of filter cabinet, with the purge pipes sticking through their flanges


Shown here is the filter mount plate.
You can see how the pipes are mounted a few inches away from the filters to let the
purge air "fan" out a bit before entering the filters, making a kind of air piston effect instead
of a sharp stream which would shorten the life of the filters.



Push bolt that holds the filters in place.
Through bolts like are used on car and truck filters are not used because
the bolt would interfere with the back purge cleaning of these filters.
Also shown is the air inlet that resides in back of the "Simplicity" deflector plate.
The purpose of the deflector plate is to shield the filters from being struck by high
velocity air, filled with bits of metal, as this would quickly blow the filters full of holes.


Each filter will handle 500 CFM, the blower is rated at 700 CFM so should have
some extra capacity even when they start to clog up.
700 CFM is not a lot of air for 5 H.P. the reason is this is a high pressure/velocity blower
which is just the ticket when you want to move metal shavings and dust.
Thats why I only need 4" pipe for this as well.
I have seen some commercial units with 15 HP and only 4" pipe.
A sawdust blower in the same horsepower would need a 12-14" pipe.


Pusher bolts holding filters in position.
The two holes are for the deflector plate mounts.


More to come....
-John

 

[cnc-me]

I will be intrested in how well you can vacum metal chips.
I see systems in wood shops all the time, but cannot recall one in a metal shop.

Not a problem unless the shavings are like a bird's nest.
Just don't try it with a sawdust blower.
This rig is closer to a low pressure vacuum pump than a blower, I have
heard them referred to as Ring Compressors before.
This one has 2 impellers instead of just one, kind of like a
2 stage air compressor.
The pipe must be perfectly smooth on the inside so nothing can get
hung up and start a clog. The Nordfab pipe is laser welded and is
much smoother than the spiral type.

 

[cdent]

Looks like a large impeller and good hp to turn it. It'll probably flow a bit more without the reducer, and running full diameter pipe as close to the pick up points as you can. Just a thought, really nice work.

 

[cnc-me]

Looks like a large impeller and good hp to turn it. It'll probably flow a bit more without the reducer, and running full diameter pipe as close to the pick up points as you can. Just a thought, really nice work.

Thanks

It might flow just a little more, but it will also overload the motor.
I'm 3-4 amps overloaded right now but once all the piping and the
filters start to clog, should be right at the maximum for
the ol' Westinghouse.

Without any pipes hooked on at all, I was reading 36-38 amps,
right in the neighborhood of what a 15 HP would take to run.
Needless to say I didn't run it for very long like that.

Also bigger pipes are not always the answer especially for
metal dust & chips. If you get to big with the pipes your velocity
goes down and all the material you are moving drops to the bottom
of the pipe and stays there, making for a smaller pipe

 

[NASTYZEN]

Cnc me, awesome work as per your usual.
Now that is one hell of a dust collector.Why do you need such a beast?

 

[bchee]

grader blade

 

[Grinder Bill]

The "Never Weld On a Pressure Vessel Boys", will have a field day with this.

I used to care but now I leave it to Darwin.

 

[cdent]

....Without any pipes hooked on at all, I was reading 36-38 amps,
right in the neighborhood of what a 15 HP would take to run.
Needless to say I didn't run it for very long like that.

Also bigger pipes are not always the answer especially for
metal dust & chips. If you get to big with the pipes your velocity
goes down and all the material you are moving drops to the bottom
of the pipe and stays there, making for a smaller pipe

It may not seem like it, but if you block half the intake and read the amps again, I bet it goes down. A motor draws the most amperage when it's doing the most work or in this case moving the most air.

The more you choke it off and the less air it moves, the lower amps it will draw, up to a point. It was probably sized for it's previous application.

Except for birdnests getting stuck, it generally takes cfm's for a dust collector to move debris and not velocity by itself. The only way to bump up the cfm's is with larger diameter piping. This is assuming your blower can handle it which it looks like it can easily.

If you found a bigger blower with the same setup, it couldn't **** up the grit any better. Only so much air will flow through at a time. Just thoughts, I still think you do great work.

 

[cnc-me]

It may not seem like it, but if you block half the intake and read the amps again, I bet it goes down. A motor draws the most amperage when it's doing the most work or in this case moving the most air.

Absolutely, I agree 100%
One more reason to keep those blast gates closed,
when they are not being used.

You have to realize that at 700 CFM a 4" pipe is big enough at the
pressure this unit runs at.
This unit is a baby, compared to the one in our woodshop.
Its a 48" Aerovent blower with a 30 horse motor with 22" main pipes, and
thats a baby, compared to the ones at a furniture plant.
Lots of times, the biggest motor in the plant, will be on the dust collector blower. 100-125 HP is not un-common at all.

 

[cnc-me]

I saw the grader blade thread. I wish I could do stuff like this. Awesome

Thanks,

 

[cnc-me]

Cnc me, awesome work as per your usual.
Now that is one hell of a dust collector.Why do you need such a beast?

Just redid the whole metal shop area with new paint and some new
drywall in places.
Just want to keep it looking nice....
At least for a while anyway.

 

[cnc-me]

Here is another update, while I round up some more pictures for the
final update.....

Shown here is the Westinghouse 5 horse motor 3450 RPM 3-Phase.
It is a special motor with the extended shaft. Someone took the wiring box off this motor,
the one in the picture is from another junk motor that was close to right size, so I used it.
The end bells were sandblasted and the main frame was sanded down with a DA and
primed with epoxy paint and urethane top-coat.
New bearings were also installed. I only wish it were totally enclosed motor
instead of an open design as it will be outside, but at least its under a roof.
The controls for the motor and air purge will be inside the shop.


Blower housing with motor installed awaiting the 2 impellers.


These are the impellers 16" in diameter made from sheet aluminum.
I really watched how these were oriented when I removed these to as to not disturb the balancing and spacing.
There is no keyway on the shaft, the hubs are cast aluminum split part of the way through, and held with allen bolts.
The North American Company still makes blowers like this in Cleavland, Ohio.
I can only imagine what this one would cost to replace.
It was from a junked machine that deburred printed circuit boards, it supplied high pressure
air to blow all the solder blobs off after the wire brushes broke them loose.
The machine was owned by the Military.


All assembled and ready for a test run


A piece of hardware cloth will go over the outlet, to keep any critters out of the blower (bigger ones anyway).

 

[cnc-me]

I'm back with the final pictures...

Control box that houses the magnetic motor starter, and the air regulator for the purge tank


Electrics are all Allen-Bradley (of course).
Good overload protection is essential on this motor because its a special design.


Pushbutton wiring


Brass Rego regulator


Completed unit sitting outside.


Have some pipes that need to be hooked up yet.