What flow rate does the VFC hold?

The standard Venturi tube corresponds to 1.13 m3/min (40 CFM) when it is used in the matching blower motor housing of a PM10 or PM2.5 high volume air sampler.

Does the controller need electrical power?

No. It is a passive machined Venturi tube with differential pressure ports, so it needs no power, no calibration electronics and no periodic sensor replacement.

Which samplers does it fit?

It fits the volumetric flow blower motor housing used across the T4 high volume air sampler range. If you are fitting it to another brand, send the housing drawing and we will confirm the dimensions.

Is a manometer included?

The pressure ports are ready for a differential manometer, but the manometer itself is optional. Many customers already have one on their sampling station.

Is the part available from stock?

Yes, standard VFC tubes ship from stock in a 21x21x30cm carton. Custom Venturi tubes for other flow rates are machined to order.

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Volumetric Flow Controller (Venturi Tube) for Air Sampler

Volumetric Flow Controller (Venturi Tube) for Air Sampler VFC

Volumetric Flow Controller (Venturi Tube) for Air Sampler

Model VFC. This is a volumetric flow controller built as a machined Venturi tube with differential pressure ports. Fitted in the blower motor housing of a PM10 or PM2.5 high volume air sampler, it holds a volumetric flow of 1.13 m3/min (40 CFM) and has no moving parts and no electronics. It is ordered both as a component for new sampler builds and as a spare part for stations already in service.

Model Number:	VFC
Product name:	volumetric flow controller
Type:	Venturi tube with differential pressure ports
Main Material:	Aluminum, black color painted
Measure:	diameter 107 mm x diameter 190 mm x 300 mm
Weight:	2.2 KGS
Packing meas.:	21x21x30cm
Shipment:	from stock
Warranty:	3 years

What Is a Volumetric Flow Controller?

A volumetric flow controller maintains a constant volumetric flow rate through a sampling train, independent of short-term changes in the aerodynamics of the sampler. The VFC model is a machined Venturi tube with two differential pressure ports, sized for high volume air samplers where the specified flow is 1.13 m3/min (40 CFM). It is a drop-in part rather than a complete instrument, which is why it is ordered for new sampler builds and as a spare for stations already in service.

How a Venturi Tube Regulates Flow

The tube narrows to a throat and then expands. As air passes the throat its velocity rises and its static pressure falls, and the pressure difference between the upstream and the throat port is related to the flow rate. The operator reads that differential on a manometer and adjusts the blower motor voltage until the specified reading is reached. Because the geometry is fixed and there are no moving parts, the relationship between differential pressure and flow does not drift.

Fitting It to a High Volume Sampler

The controller mounts inside the blower motor housing of a PM10 or PM2.5 high volume air sampler. The black painted aluminum body measures diameter 107 mm x diameter 190 mm x 300 mm and weighs 2.2 kgs, and it can be removed for cleaning with ordinary hand tools. It is a direct fit for the volumetric flow motor housing used across the T4 high volume platform, so no adapters or cutting are needed.

Applications, Packing and Availability

Volumetric flow controllers are used by air quality monitoring networks, environmental laboratories and integrators who assemble or service high volume samplers, and by OEM partners buying the part for their own products. Custom Venturi tubes machined for other nominal flow rates can be produced to order when a programme uses a non-standard reference flow. Standard units ship from stock in a 21x21x30cm carton and carry a three-year warranty.

No Moving Parts, No Electronic Drift

The volumetric flow controller is a machined Venturi tube with differential pressure ports. There is no electronics board, no sensor to recalibrate and nothing to wear out, so the flow reference stays stable through long unattended campaigns and behaves the same in hot, cold or humid weather.

Holds 1.13 m3/min in High Volume Samplers

Fitted inside the blower motor housing of a PM10 or PM2.5 high volume air sampler, the Venturi tube produces a pressure differential proportional to flow. The operator reads that differential on a manometer and adjusts the motor voltage until the specified value is reached; the fixed tube geometry then corresponds to a volumetric flow of 1.13 m3/min (40 CFM).

Black Painted Aluminum, 2.2 kgs

The tube is machined from aluminum and finished in black paint, measuring diameter 107 mm x diameter 190 mm x 300 mm and weighing 2.2 kgs. It drops into the matching motor housing without modification and can be removed for cleaning with ordinary hand tools.

Available from Stock

Standard VFC tubes are held in stock and packed in a 21x21x30cm carton for immediate shipment, which suits buyers who need spare flow controllers or who are assembling samplers in the field. Custom Venturi tubes for other nominal flow rates can be machined to order.

Spare Parts Backed by the Factory

As a manufacturer of air sampling hardware since 2002, T4 AIR SAMPLER supplies spare and replacement parts for the whole high volume platform, with OEM marking and export packing available. The volumetric flow controller carries a three-year warranty.