I am trying to put a local flow gauge (unpowered) across a Venturi. I have a range of 0-500 m3/hr and vendors are all leading me to install a powered transmitter for that purpose.

Is it possible to get a differential pressure gauge that measures in terms of flow in m3/hr or are only ones with a span of sqrt(0-10) commonly used?

sshad at engro. com

 

Yes, It is possible to have an unpowered dp gauge across your Venturi, but it would be a differential pressure gauge with a custom scale.

Custom scales are possible but are expensive because they are made to order and the cost of redrawing the scale manually is often more expensive than buying a powered unit.

Powered indicators are normally standard (off the shelf) items that can be configured to the flow.

It is not easy to recommend a manufacturer of a gauge, because you did not give us the static line pressure. This will change the recommendation.

I trust this helps.

Malvern
www.coulton.com

 

You could also make your own manometer style gauge with a scale marked off in engineering units. Depending on the process fluid and pressure this could be as simple as a length of plastic tubing.

The advantage of using a DP cell is you can get the square root function and a digital display. You don't need anything else but a power supply (12-24 VDC) and indicating DP cell. You will likely find that a DP cell is cheaper than a quality DP gauge with special scale.

Roy