Water Flow Measurement...

[Ace1985]

I've been at a breakdown today where a part is spraying water through a calibrated hole which then funnels into a 10mm pipe and via a very intricate measurement unit that is basically 2 x oval cam'd/geared peices in a seat which 1 of the cam's has 2 x magnets which trigger reeds for your PLC input.

Basically, the hardware isn't really suitable for purpose. They're getting repeat issues with the very fine teeth (about 0.5m pitch at a guess) clogging up with the slightest debris (on a 10 micron filtered system) plus other issues.

The limits are 40cc to 150cc for a pass with nominal flow being about 75cc for a good part.

Anyone got experience on water flow measurement devices that increment on a 1cc scale with a max of 200cc?

With it being a 2 hour drive away, i'd like to replace it with a more robust system. Any help appreciated.

Thanks.

 

[btrueblood]

One of the simplest flow measurement systems is a bucket and a stopwatch. A clever take on that concept is a piston in a cylinder, with valves on both ends of the cylinder - time the motion of the piston across an interval of distance and bingo, instant flow rate. And traceable to NIST with simple measurement tools.

 

[itsmoked]

Ace; You're in a horrible zone. I've been in it for a year, trying to measure the flow in that region is a problem.

I'm not clear on your process. If you control the time of the flow thru the orifice then you can easily and accurately measure the flow by simply weighing the water after the fixed period. In the gross form you just fill a container sitting on the appropriate scale and do some simple math. Then open a valve to drain the container - ready for the next cycle.

You can flip that around and use the supply container if your scale has sufficient resolution to measure a much larger weight.

Keith Cress
kcress -

http://www.flaminsystems.com

 

[danw2]

Siemens' pocket flask sized coriolis low flow meter has a high end flow rate of about 100g/sec (water 100cc/sec).

http://www.automation.siemens.com/w1/automation-technology-sitrans-fc300-dn-4-18648.htm

 

[Mrg1]

How deep you have to go you see the surface sometimes flows faster than the deeper water it's due to the moon and tides. If your building some type of generator thats all you need to know is the surface speed unless you are just going to use volume and speed in sec 1 g = 1 cc. Call someone at a dam.

 

[Mrg1]

If you are turning a generator or any type wind generators or building a generator heres' a good cite to have.

http://www.wikiplc.com/index.php?option=com_content&task=view&id=43&Itemid=34

 

[roydm]

Brooks make a pair of very small coreolis meters, Quantum Series