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Starting Member


Thursday, November 5th 2015, 8:18pm

Venturi Injectors

Does anyone know anything abut venturi injectors?

I've been working on a project for some time, which involves using a
venturi injector to dose a small amount of chemical into a flow of
water. During the pilot stage, everything was linear, and worked fine,
but I had to fit into into a smaller space, so folded it through 2
elbows and the venturi refused to pull a vacuum. Checked online, and
found that a pressure drop between the inlet and outlet of the venturi
is required (so why did it EVER work?). So I revised the layout
(see here) to put a pressure regulator and filter across the ends of the
venturi, which should create just such a pressure drop, but still no

I'd really like some help! :huh:


Supreme Member

Posts: 5,248

Location: Metro NYC


Friday, November 6th 2015, 7:51am

Go back to your pilot device that worked, and proceed from there. Your "need to fit" appears to have been vetoed by the physics of turbulent water.

By the way, most venturi injector assemblies have the entire flow passing through the venturi, in order to generate the needed suction force. Your pictured assembly is anything but that.

This post has been edited 1 times, last edit by "Wet_Boots" (Nov 6th 2015, 8:16am)

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