How about this Flow Meter
 

One of the members over ar XS was gracious enough to send me a Dwyer VFB-86-SSV flow meter. I was just curious about what you guys with ur amazing test rigs have to say about this flow meter. Here is a pic of it

http://www.xtremesystems.org/forums/...chmentid=26361

Interesting..
We have similar looking ones at work for adjusting gas flow. If its the same type.. then it looks like it would add quite a bit of restriction to the loop by itself?

What are those knobs for? Adjusting flow rate? If so that would be nice. Looks like a flow killer but if you have a good pump then who cares. Looks like 1/4" ftp connectors on that model. Accuracy is a little poor. Here is a PDF of that meter. http://corp.watersurplus.com/techlib...fa&vfb_cat.pdf

I am bidding on a bigger version of the same brand on ebay right now.

+/- 5% full scale, i.e. +/- 0.25 gpm.

It's a start, but when Bill sees this, he'll slam you like he did me:
http://forums.procooling.com/vbb/showthread.php?t=6377

His are the VFB model so it is +-3%.

yep.. its the +-3% model... the flow restirction is rather high. the guy who is sending it to me says they are 1/4npt.. if that is correct, then getting non flow killing fittings wont be an issue.

You modded one of those right? Got to thinking you probably just destroyed the calibration of the meter by enlarging the inlet.

Yep... 10...

EDIT: changed to correct answer

A little more detail as I found the thread. Here is his post with pics of the mod:
http://forums.procooling.com/vbb/sho...5&postcount=27

oooh
not good

yah.. well i got two of them. im gonna run some tests right now with the RBX and new maze4 danger den just sent me. ill let u know how they do on the iwaki for max flow.

its a pitty how dwyer designed these guys as they are way to restrictive. could have done it and calibrated it with bigger nozzles and such..

either way its ok since i got 2.

well i got some numbers now.. boy was that not fun.

anyway. it gets 4.2gpm with just the tubing and the flow meter
Maze4 Acetl is 3.4gpm
RBX with #1 insert is 2.6gpm.

Please note that there is rather huge restriction in the system with the flow meter as the max flow on the pump is around 8gpm without restriction. and based on the pq curve it looks like with just the flow meter the curve is at the 11ft of head mark. pretty high if u ask me.

EDIT: Bill do u know of a way to calculate what the flow rate would be without the flow meter so i can adjust all of my results to that for testing.

my first flow meter was a Brooks rotometer,
hooked it up to a Little Giant pump and read the pressure
and sold it on eBay for $10

went to a good paddle wheel (NOT Swissflow) - which pH then used
and have been on (relatively) non-invasive mag flow meters ever since

that flow meter is not suitable for your intended application

BTW, I noted your acknowledgment of receiving review items from another vendor
this will not happen from Swiftech until I am comfortable with your technical acumen
so far you have shown that you can ignore good advice,
but again:

change the flowmeter (has shit accuracy for this work anyway)
get something with a numerical readout (not the parallax error from your reading a bouncing bobbin)

why did you not get the pd info from Dwyer ?

Agree completely. I got the larger Dywer I am using now and would not submit review data with it. Pretty neet for messing around though.

Have been looking for a decent numerical flow meter but have yet to come up with something decent. Bill what spacific specs would you look for?

one has to have a plan, patience, and perseverance
(sounds too much like life)
mag flow meters can be had cheaply on eBay and LabX
learn the mfgrs, and which flowtubes can be used with different mfgrs xmitters
I prefer Danfoss (one more digit resolution), but Rosemount, Foxboro, Yokogama, Brooks, Sparling all work for me

I used to believe that a 1/4" flowtube was necessary for low flow rate accuracy, but I recently put a 1/4" and a 1/2" in series and compared the flow indicated and dp
- I was surprised to find that the difference between the 2 was a nominal 0.005% (the Rosemount 1/2" being 'high')
-> based on this I would suggest that 1/2" flowtubes be used for our type and range of testing

note (again) that the flow meter does not need to be in the system, anything (wb, rad) can be 'calibrated' by generating a dp/flow curve, and the flow then known by reading the differential pressure across that item
- note that the ASME size of the pressure tap holes is D/10

http://thermal-management-testing.co...alibration.gif

http://cgi.ebay.com/ws/eBayISAPI.dll...MEWN%3AIT&rd=1

You're bold posting auctions you're bidding upon :)

err, I hope its closed - I paid for it !

a note to flowtube purchasers: the plate with the cal # MUST be attached, w/o that # it is scrap

Man I have to get my head above water at work. I still haven't even bought the flanges for the flowmeter brucoman sent. I take it from your above graph that the 1/2" flowtube isn't a bad thing after all, which is good for me. I'll measure the hole diameters and size of the flange I need and order it tonight. It's stupid not to be using that flowmeter, esp since it's got a readout lcd on it.

Thanks for the input. I was pondering getting that little Swissflow SF800 or similar but might just keep an eye out for a magnetic. What meter have you been using pH? Swissflow?

I actually had a fair amount of trouble with the Swissflow. It works sometimes and sometimes it doesn't work at all. The output is also pretty jumpy. I can't find anything wrong with it and some days it runs just fine. I use a GPI paddlewheel type flowmeter right now (1% accuracy) and I have a magnetic flowmeter that Brucoman sent me which needs some flanges and gaskets to work properly.

1/2"NPT x 150# flange, PVC or CPVC
get a pair of full face gaskets too (easier than cutting flat rubber ones
take a knife and remove the lip at the end of the threads (on the flange face side)

you will also need 1/2"NPT copper tube adaptors x the copper tubing size of your choice with grounding straps (the flowtube must be grounded to the fluid both ends)
- I use 1/2" CTS (5/8" OD) as I run 5/8" hose generally on the bench; which is where I have pressure taps as well

Bill, the only reason i got the flowmeter I have is due to serious lacking in funds. If it was up to me I would buy the best gear available. But being a poor college student, it makes amasing large sums of money for good test equipment a tough task. But i will check out ebay to see if i can find any deals on gear. I'll show them to you to see if you aprove as you are the resident expert on test equipment.

hey pH any chance of a hand me down flow meter. the gpi im refering to.


I will contact Dwyer about hte pressure drop of the unit.

http://cgi.ebay.com/ws/eBayISAPI.dll...MEWN%3AIT&rd=1

$10 is not a lot of money
I would like to fly, but I cannot afford a plane

if you are going to bid on something, do not post it

no offense bill, but finding a mag flow meter for 10 dollars is not a common find. infact ebay doesnt even have any mag flow meters right now. Only the meter and not hte flow tube and its starting bid is 100 dollars.

Trust me i wont post it. lol.