Searching \ for '[EE] Machine Venting' in subject line. ()
Make payments with PayPal - it's fast, free and secure! Help us get a faster server
FAQ page: www.piclist.com/techref/index.htm?key=machine+venting
Search entire site for: 'Machine Venting'.

Exact match. Not showing close matches.
PICList Thread
'[EE] Machine Venting'
2008\01\24@002150 by Forrest Christian

flavicon
face
So, I'm putting in (finally) a new-to-me wave solder machine.   It has a
4" duct attachment, and the manual indicates that some sort of exhaust
fan capable of 400CFM needs to be attached.

I'm having a bit of an issue finding the source for such a beast.  I was
hoping to find something >400CFM already in a 4" duct (even though 4" is
a bit small for 400CFM), but no luck.

I know some on the list have either a wave machine or other production
equipment with similar (or more aggressive) ventilation
requirements.....  so I was wondering if anyone could provide me some
insight into how to pump this stuff outdoors...   I think I get to pump
this out through a hole in one of the garage doors in the new shop, so
smaller hole is probably better....

-forrest

2008\01\24@005650 by Bob Blick

face picon face
Any V-8 engine running at full throttle ought to be able to pull 400 CFM
through that duct. Other than that, I'm utterly useless :)

Cheerful regards,

Bob


Forrest Christian wrote:
{Quote hidden}

2008\01\24@014155 by Apptech

face
flavicon
face
> So, I'm putting in (finally) a new-to-me wave solder
> machine.   It has a
> 4" duct attachment, and the manual indicates that some
> sort of exhaust
> fan capable of 400CFM needs to be attached.


400 CFM into about 0.1 0.1 foot^2 = 4000 fpm at no
compression or about 65 fps or 45 mph. Even with some
compression that's "quite a gale".

That seems to be an immense amount of air for ventilation
alone. Is there perhaps a factor of 10 or even 60 (cfh)
involved?


           Russell




2008\01\24@014906 by Forrest W Christian

flavicon
face
Bob Blick wrote:
> Any V-8 engine running at full throttle ought to be able to pull 400 CFM
> through that duct. Other than that, I'm utterly useless :)

I know the feeling exactly....

I really should pay a HVAC engineer to do this (and the make up air as
well), but finding a HVAC engineer who will take the time to do this
small of a job in my area is not likely...  heck, I'm involved with
trying to get a quote for a HVAC redesign for a building I'm involved
with and can't get anyone to even look at the project...

I will probably end up putting some sort of way-too-large fan on a
way-too-large duct with a short piece of 4" duct to connect to the
flange on the machine... and hope that I'm in the 400cfm range when I'm
said and done.

-forrest

2008\01\24@022230 by Forrest W Christian

flavicon
face
Apptech wrote:
> 400 CFM into about 0.1 0.1 foot^2 = 4000 fpm at no
> compression or about 65 fps or 45 mph. Even with some
> compression that's "quite a gale".
> That seems to be an immense amount of air for ventilation
> alone. Is there perhaps a factor of 10 or even 60 (cfh)
> involved?

The specs for the current version of this machine spec 300CFM or
500m3/h.    The Manual says "Use a 400CFM (150m3/h) exhaust fan to
remove fumes beyond the working area" - which is obviously in error
(either the m3/h or the cfm number is off).

Knowing what I know about the amount of fumes produced by the wave
solder process (dipping a board coated with flux into hot solder wave),
3-400CFM does not seem excessive as far as the volume of air needed to
move the fumes outside.

However, the 4" hole provided seems rather small for this application.

-forrest

2008\01\24@032035 by Apptech

face
flavicon
face
> Knowing what I know about the amount of fumes produced by
> the wave
> solder process (dipping a board coated with flux into hot
> solder wave),
> 3-400CFM does not seem excessive as far as the volume of
> air needed to
> move the fumes outside.
>
> However, the 4" hole provided seems rather small for this
> application.

My friend Ken, who has a wave soldering machine for sale (in
NZ) says:

_____________________

Russell,

400 cfm sounds way too high  - maybe it should be
litres/min.

I have a Seho Compac 1018 wave soldering machine (which is
for sale in
excellent condition if anyone wants it) but sadly the
operating manual says
nothing about the rate of extraction it requires (although I
know that when
it was in use it would have been way less than 400 cfm).

Note that it's not sufficient to just have a fan of the
required rating  -
the whole extraction system must be engineered to account
for the frictional
and turbulence losses etc. in the ducts such that the
overall system
extracts at a sufficient rate.

Regards,

Ken Mardle


2008\01\24@043936 by Jinx

face picon face
> The specs for the current version of this machine spec 300CFM
> or 500m3/h.    The Manual says "Use a 400CFM (150m3/h)

300cfm = 510m3/h => 400cfm = 680m3/h

88cfm = 150m3/h

2008\01\24@044941 by Forrest W Christian

flavicon
face
Looking at the spec for the Seho Golean 1030 (a in-production machine)
which has similar capabilities to mine ( 12" single wave), says that
it's exhaust requirement is 2 x 250 m3/hr (it appears to have two vent
connectors).  500 m3/hr converts to 300CFM, which is in line with my
machine specs......

(See http://www.seho.de/files/upload/GoWave%201030.pdf )

-forrest

Apptech wrote:
{Quote hidden}

2008\01\24@050229 by Forrest W Christian

flavicon
face
Jinx wrote:
>> The specs for the current version of this machine spec 300CFM
>> or 500m3/h.    The Manual says "Use a 400CFM (150m3/h)
>
> 300cfm = 510m3/h => 400cfm = 680m3/h
>
> 88cfm = 150m3/h
>

I think I pointed that out.

I really think that someone was careless when doing the manual.  I think
the correct figure is "300CFM (510m3/hr)", which is pretty much
consistent with all similar machines that I've found, and their current
spec sheets for this model on the web site.....  I can see how someone
could typo a 4 for a 3, and transpose the 1 and the 5.....

It should be noted that modern range hoods are easily in the 3-400CFM
range, so it's not unrealistic to believe that a 12" wave solder machine
wants that much airflow.

My current theory is that I'm going to have to end up with a 12" duct
and a 12" duct fan (650CFM, Free Air) to do most of the path, and then
choke it down to the 4" right next to the machine, and hope that I end
up with sufficient airflow...

-forrest

2008\01\24@051728 by Carl Denk

flavicon
face
This is a branch of engineering in itself with application mainly in the
machine tool industry where the cutting tools generate much heat which
vaporize liquids, and also in the HVAC industry where heating/cooling at
doorways to keep the conditioned air in and unconditioned air out.
Considerations include ambient airflow (drafts) and air
velocity/direction at air inlets/outlets. Sorry can't offer more help,
probably the ASHRAE manual would offer some guidance, it's the turf of
some mechanical engineer type.

Forrest W Christian wrote:
{Quote hidden}

2008\01\24@101800 by Eoin Ross

flavicon
face
I recently measured the breeze from our 25HP air compressor.
The "intercooler" intake runs at 50 mph, with the exhaust running 25 mph - and a 10 deg F temp rise.
1800 CFM - needless to say it makes racket!

The higher the speed, the higher the friction losses and noise.
http://www.hartandcooley.com/flex/Air%20Duct%20Calculator.xls  
This recommends 900 ft/m MAX for residential - of course thats for heating/cooling not fume extraction.

http://www.elitesoft.com/web/newsroom/vent.htm
"These unique components not only require special consideration in calculating their pressure loss, they also greatly influence the design of the duct system. For example, a hood usually has slots through which particulate or gases are drawn through. For the hood to work properly, the connecting ductwork must allow sufficient velocity (typically 3,500-4,500 fpm) so that the particulate stays in suspension of the transporting air. "


>>> spam_OUTapptechTakeThisOuTspamparadise.net.nz 24 Jan 08 01:41:22 >>>
> So, I'm putting in (finally) a new-to-me wave solder
> machine.   It has a
> 4" duct attachment, and the manual indicates that some
> sort of exhaust
> fan capable of 400CFM needs to be attached.


400 CFM into about 0.1 0.1 foot^2 = 4000 fpm at no
compression or about 65 fps or 45 mph. Even with some
compression that's "quite a gale".

That seems to be an immense amount of air for ventilation
alone. Is there perhaps a factor of 10 or even 60 (cfh)
involved?


           Russell




2008\01\24@115936 by Marcel Duchamp

picon face
Forrest W Christian wrote:

http://www.mcmaster.com

2008\01\24@123903 by Carl Denk

flavicon
face
and
http://www.grainger.com/Grainger/wwg/start.shtml

They probably much more into the heating, ventilating area, but
difficult for an individual to get an account there, business is no
problem. They have very large inventory warehouses scattered around the
USA, including one in the Cleveland, Oh. area. 95% of the time my nickel
dime orders are shipped same day, and I have them next. Amazing nearly
everything in the catalog is stock. In Atlanta they have a super market
type store with large warehouse attached. I was there one morning, they
had one pressure meter in stock, I wanted 2, placed the order, figuring
3 day UPS to Cleveland, it got shipped same day from Cleveland and set
on our porch for 2 days. :)

Marcel Duchamp wrote:
> Forrest W Christian wrote:
>
> http://www.mcmaster.com
>  

2008\01\24@132342 by TGO Electronica

flavicon
face
We have an Econopak wave soldering machine and it has 3 venting holes, one
on top 6"dia. and two on the back 4"dia each. So a single 4" hole seems
really small.
Our machine already came with an external exhaust fan, so I don't know the
specs, but it is pretty strong, as when it is working you can feel air being
drawn in all around the machine, and it is quite noisy if I may add.

Gabriel
TGO Electronica

{Original Message removed}

2008\01\24@133451 by Dwayne Reid

flavicon
face
I used 8" round duct when we installed our wave-solder machine.  The
fan enclosure is mounted on the wall at the rear of our building -
right next to where the exhaust exits the building.

The fan enclosure uses a pair of 10" or so diameter fans removed from
old DEC racks.  The 2 fans are in series with each other - I seemed
to get better draw when I added the 2nd fan.  Those fans move a LOT of air.

As a point of interest, I also added a fume hood on the other wall of
the little room containing our wave-solder machine.  In other words,
the wave-solder machine is flat against the west wall of the little
room.  I extended the ducting across the room to a fume hood on the
east wall of that same room.  Dampers in the duct allow one or the
other to be selected.

The fume hood is great when we are applying conformal coating to PCBs and such.

Hope this helps.

dwayne


PS - I *think* that our machine has a similar 4" outlet.  We capped
it off - our exhaust is instead taken from the end of the machine
where the boards exit the solder wave.  We built an enclosure that
sits over the end of the conveyor rails and is sealed to the end of
the machine (its flush with the top of the machine).  The exhaust
comes from the top of that enclosure.

Both that and the fume hood work well - barely any smell of flux in
the room while wave-soldering, no smell of solvents when using the
fume hood.  No smells of any sort outside the wave-solder room.

dwayne


At 10:21 PM 1/23/2008, Forrest Christian wrote:
>So, I'm putting in (finally) a new-to-me wave solder machine.   It has a
>4" duct attachment, and the manual indicates that some sort of exhaust
>fan capable of 400CFM needs to be attached.


--
Dwayne Reid   <.....dwaynerKILLspamspam@spam@planet.eon.net>
Trinity Electronics Systems Ltd    Edmonton, AB, CANADA
(780) 489-3199 voice          (780) 487-6397 fax
http://www.trinity-electronics.com
Custom Electronics Design and Manufacturing

2008\01\24@134957 by TGO Electronica

flavicon
face
I don't know how relevant this is, but I was checking the specs for common
home range hoods and they state extraction rates from 200 to 600CFM, and
some up to 1200CFM.
I don't know if this is true, but it sure seem like a lot for such a small
device.

Gabriel
TGO


{Original Message removed}

2008\01\24@145253 by Charles Craft

picon face
Yeah but you gotta figure in pressure and distance.
A range hood going out the wall has almost no back pressure.
Putting your thumb over the end of the hose (i.e. the 4" exhaust port)
and pushing it 50' is going to make it harder.

{Original Message removed}

2008\01\28@113621 by Forrest Christian

flavicon
face
I'm going to reply to myself for list archive purposes.

I have discovered that numerous companies make such a beast.....  They
are actually typically used for dust collection purposes in a wood
shop..... or sometimes used for exhaust from laser engraving/cutting
machines...
One example is at
http://www.harborfreight.com/cpi/ctaf/displayitem.taf?Itemnumber=94029

-forrest

{Quote hidden}

More... (looser matching)
- Last day of these posts
- In 2008 , 2009 only
- Today
- New search...