Precise Flow · Calibration · Test Equipment

H800 Classic venturi tubes

Classic venturi tubes H800 are manufactured according to standard DIN EN ISO 5167 part 4 with flange connection or for welding. They are the first choice for the flow measurement of gases, vapours and liquids, when short length and low pressure drop are required.


Compared with other differential pressure transducers according to ISO 5167 clearly shorter straight inlet/outlet sections are required. In addition, the weight of big venturi tubes completely manufactured of sheet steel is clearly lower than the weight of comparable venturi nozzles. The remaining pressure drop is approx. 15 up to 20% of the measured differential pressure.

Classic venturi tube H800
Classic venturi tube H800

Product features include:

  • Throat diameter d of 10 up to 800 mm
  • Diameters of DN 25 up to DN 1000
  • Straight inlet/outlet: min. 4 x DN / 2 x DN
  • Connection by flanges or welding
  • Vacuum or pressure operation
  • Quick response time and good accuracy
  • Very good long-term stability, no moving parts


Venturi tubes are welded structures of steel or stainless steel, mainly with round cross-section. They consist of an inlet cylinder, an inlet cone, followed by the cylindrical throat and the outlet cone. Classic venturi tubes are designed as different types according to the manufacturing method of their inner surfaces. A distinction is made between venturi tubes with treated inlet cone, inlet cylinder and throat, as well as a rough inlet cone welded of sheet steel.


Classic venturi tubes have very low remaining pressure drops according to the manufacturing of the inlet cone and the angle of the outlet cone due to good flow control. Plus and minus pressure tappings are carried out in the tube wall on the inlet and at the constricted area in the throat by one or several single bores. It is recommended to connect them by a ring line in case of larger diameters.

H800 classic venturi tubes

Low pressure drop and short length

More information and technical details can be
found in the data sheet

Data sheet:

Data sheet H800

Additional information
on this subject:


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