The venturi tube consists of a gradually decreasing convergent inlet followed by a cylindrical throat and a gradually expanding conical section called the “divergent”. The conical section allows the fluid to nearly regain its original pressure.
Due to the fact that a major part of the output pressure is regained, the venturi tube is particularly suited for the measurement of flow rates in systems where a low pressure differential is needed.
The venturi tube is a robust, reliable device. It can measure a wide range of clean liquids and gases. It ensures the lowest pressure loss in the family of primary flow elements as well as the lowest upstream and downstream straight lengths requirements.
Deltafluid offers different types of venturi tubes :
- Smaller sized units are machined from a unique bar stock.
- Larger sized units are manufactured from rolled and welded sheets.
- Cast venturi tubes can be manufactured as well; they can be made by casting in a sand mould or by other methods which leave a finish on the surface of the convergent section similar to that produced by sand casting. The throat is machined and the junctions between the cylinders and cones are rounded (rounded angles according to standards) for optimised flow.