The orifice flowmeter has a simple manufacturing process, convenient installation, and low cost. Therefore, it is widely used, but special attention should be paid when using it. Especially when measuring the flow of corrosive media and media containing dust, it is necessary to frequently observe whether the measurement results are accurate, to prevent the measurement error caused by corrosion and blockage of the pressure tap from being too large or the phenomenon that measurement cannot be conducted at all. The orifice plate should be cleaned every year for major maintenance, and a new orifice plate should be replaced immediately when serious corrosion is found.

1. The measured medium shall be filled with all pipe sections and flow continuously.

2. The flow beam (flow state) in the pipe should be stable.

3. The measured medium shall not change phase when passing through the orifice plate (for example, the liquid shall not evaporate, and the gas dissolved in the liquid shall not be released), and it shall be single-phase. For media with complex components, they can only be used if their properties are similar to those of single-component media.

4. Condensate or dust precipitated during gas (steam) flow measurement, or gas or sediment precipitated during liquid flow measurement, shall not accumulate near the orifice plate in the pipe or in the connecting pipe.

5. When measuring the medium flow that can cause the orifice plate to block, the core must be cleaned regularly.

6. On the inner surface of the pipe 2D away from the front and rear ends of the orifice plate, there is no protrusion or visible roughness and unevenness. For standard nozzles. Standard Venturi nozzle and standard Venturi tube, these conditions apply.