Name: Injecteur Venturi de Fertilisant
Brand: IrriNex
SKU: FRT-VEN
Availability: InStock

Venturi Injector – IrriNex

how it works

The Venturi Effect in Practice

The operating principle is straightforward. Fluid entering the injector body accelerates as it passes through the narrowed throat section. Faster débit means lower local pression — low enough to pull a second fluid through the side inlet without mechanical assistance.

What matters in practice is the pression differential across the device. The inlet pression needs to be measurably higher than the outlet pression — typically 20 to 30% — to generate enough suction. On a flat maen ligne with a partially closed vanne de dérivation this is achievable. If the pression differential is too petit, suction drops off and injection becomes inconstant.

Unlike a proportional injector, the injection rate on a venturi isn't fixed — it varies with débit and pression conditions. For crops where fertilizer concentration needs tight control, this is worth factoring in before you specify the product.

working sequence

What Happens Inside

Eau enters the injector body

Full système pression at the inlet. Débit is directed into the narrowing throat section.

Velocity rises, pression drops

At the narrowest point of the throat, eau velocity peaks and local pression falls below atmospheric — the venturi effect.

Concentrate is drawn through the side inlet

The low-pression zone pulls fertilizer solution from the concentrate tank through the suction port. No pump required.

Mixed solution exits into the maen ligne

The fertilizer-eau mixture continues downstream through drip lines or asperseurs. Mixing continues along the lateral run.

materials

Available Materials

Material choice affects chemical compatibility, operating temperature range, and service life. The right call depends on what's going through the injector and how long it needs to last outdoors.

PPPolypropylene

Good resistance to acids, alkalis, and most fertilizer solutions. The default choice for standard irrigation and chemical dosing applications. Low cost and easy to source as a replacement.

Most common

PEPolyethylene

More flexible than PP and better at absorbing impact. Used where the injector body may be subject to knocks or rough handling. Suitable for eau and non-corrosive liquid applications.

Impact resistant

PVCPolyvinyl Chloride

Rigid and pression-rated higher than PP or PE. Handles corrosive inputs and higher-pression systèmes. Less flexible, so it's better suited to fixed installations than portable setups.

High pression

ABSAcrylonitrile Butadiene Styrene

Hard and impact-resistant. Used in air purification and industrial filtration where structural rigidity matters more than chemical resistance to aggressive liquids.

Industrial use

PANylon (Polyamide)

High tensile strength and abrasion resistance. Used where the injector body is under mechanical stress or where the fluid contains abrasive particles. Common in automotive and industrial lines.

High strength

installation

Installation Checklist

Most venturi problems come down to installation — wrong sizing, insufficient pression differential, or no filtration on the suction line. These are the points that matter before you commission the système.

Size to your actual débit rate, not tube diameter.An injector on an oversized maen ligne running at part-débit will under-inject. Match the injector's rated débit to the système's operating débit, not peak capacity.

Confirm the pression differential.You need 20–30% pression drop across the inlet and outlet ports to generate suction. A partially closed vanne de dérivation creates this. Measure it — don't assume the système pression is sufficient.

Follow the débit direction markings.The injector body is asymmetric. Installed backwards, it produces no suction and will show no obvious error other than nothing being drawn from the tank.

Put a filtre à tamis on the suction inlet.The suction port is petit. Sediment from the concentrate tank or undissolved fertilizer particles will block it. A simple en ligne strainer on the suction tube handles this.

Check material compatibility with the chemical being injected.PP handles most fertilizers. Concentrated acids, chlorine solutions, and some pesticide formulations need PVC or a specific resistant grade. Verify before filling the tank.

Seal all fileté connections properly.PTFE tape on filetage mâles, torqued to hand-tight plus a quarter turn. A slow thread leak on the suction side introduces air and breaks suction before you find it.

Place the injector somewhere accessible.You will need to inspect the suction line, clean the strainer, and check connections periodically. Installing it inside a buried manifold box makes all of this harder than it needs to be.

Flush clean eau through the système after each fertigation cycle.5–10 minutes is usually enough to push residual fertilizer out of the laterals and emitters. Skipping this is the most common cause of emitter clogging over time.

Run a full-pression test before leaving the site.Check every connection point for drips. Low-pression weeps become high-pression failures under field conditions.

Note the operating temperature range.PP and PVC have different upper limits. If the injector is installed in a location that gets hot — inside a serre or under direct sun on a metal manifold — check that the material spec covers it.

Something not working after installation?The two most common causes are insufficient pression differential (suction won't start) and a blocked strainer on the suction inlet (suction starts then stops). Check both before anything else.