Throttling flowmeter

The throttling flowmeter is an early and widely used measuring device for measuring flow, with the longest history and the largest usage. The commonly used types now are circular orifice plate and conical inlet plate. Their working principle is to add an orifice plate throttling element in the fluid pipeline, and introduce a pressure difference transmitter through a pressure guiding pipe to measure the pressure difference upstream and downstream of the throttling element. Based on the measured pressure difference, the instantaneous value of the flow rate is calculated.

When the water in the pressure pipe is not flowing, in colder regions, the orifice plate pressure pipe installed outdoors in winter is prone to freezing and cracking (freezing), which makes the differential pressure instrument unable to work properly. When measuring dirty sewage, the orifice plate needs to be cleaned regularly. If not cleaned in a timely manner, the measurement accuracy will decrease, the pressure tube will often be blocked by dirt, and the instrument cannot be used. When measuring flow using orifice plates, there are disadvantages such as high pressure loss and large maintenance requirements.

Therefore, changing the pressure measurement method, such as using the radial distance pressure measurement method, can reduce the impact of orifice plate contaminants.