Venturi Differential Pressure Flow-Meter Tek-DP 1640A. A perfect flow measurement solution. Venturi Flow-Meters are used for a wide range of clean liquids and gases. Our Venturi Flow-Meters are low-pressure metering devices with a superior design. As a result, one can expect constant accuracy and greater capacity. In addition, one can also expect high-pressure recovery, and minimal permanent pressure loss. The Venturi tube can be installed in any position. Therefore, feel free to install horizontally, vertically, or any angle in between. The Tek-DP 1640A is available in two different models. One model is for normal liquid applications. Another model is for wet gas applications. Venturi Differential Pressure Flow-Meter.