Print

[Roger2561]

Hi folks, Would someone be so kind to educate me on venturi fittings and in what kind of application would they work?  I'm not redoing anything, just curious as to what they are and what they do.  Thanks, Roger

[BoilerHouse]

Hi Roger

I'll give this a shot and perhaps others may add to it.  At work we use venturi's in a couple of different ways.  A short tapered nozzle (aka a venturi) is within a closed pipe.  The fluid travels through this nozzle.  At the outlet of the nozzle, the fluids velocity increases and the pressure drops.  We measure the pressure drop just upstream and just downstream of the nozzle.  The pressure drop is proportional to the flow.  So by measuring pressure drop, we can calculate flow.  We can also use venturi's to do work.  A short tapered nozzle is within a tee in a piping system.  A fluid passes through the nozzle, velocity increases and pressure drops.   If the nozzle is designed properly, the pressure drop is so much that a vacuum is created.  We often use this vacuum to draw liquid chemicals into our piping system at the tee.  A quick example around home that I can think of are paint sprayers or engine shampoo sprayers.

[mlappin]

Not exactly a fitting but both our combines and all our larger tractors have either a venturi in the muffler or in the straight pipe, the vacuum created by the venturi is used to suck dust out of the air cleaner to extend service intervals of the air filter.

WE had a stainless tank built that fits over the rear axle of one of our four wheel drive tractors and for agitation we use a venturi nozzle. A small amount of liquid from the bypass after the pump flows thru the venturi assembly which is submerged in the spray tank and in the process picks up additional fluid from ports around the nozzle thereby increasing the actual flow while decreasing the velocity. In this case volume is needed more than velocity to maintain the suspension of whatever chemical might be used at that time. Without the venturi nozzles it would require a much larger and expensive pump in order to supply enough flow for agitation and to supply the spray boom with the required volume.

[yotehunter66]

Ventures are used to creat a pressure differential for either measuring something or for delivering something.