The rotor flowmeter consists of two components, one of which is a conical tube that gradually expands from bottom to top; The other component of the rotor flowmeter is a rotor that is placed in a conical tube and can move freely along the centerline of the tube. When measuring the flow rate of a fluid with a rotor flowmeter, the measured fluid flows in from the lower end of the conical tube, and the flow of the fluid impacts the rotor, generating a force on it (the magnitude of this force varies with the flow rate); When the flow rate is large enough, the force generated lifts the rotor and raises it. At the same time, the measured fluid flows through the annular section between the rotor and the conical tube wall, and exits from the upper end. When the force acting on the rotor during the flow of the measured fluid is exactly equal to the weight of the rotor in the fluid (known as the displayed weight), the force on the rotor is in equilibrium and stays at a certain height. Analysis shows that; The position and height of the rotor in the conical tube correspond to the flow rate it passes through. Therefore, by observing the position and height of the rotor in the conical tube, the corresponding flow rate value can be obtained.

In order to prevent the rotor from touching the pipe wall when moving up and down on the centerline of the conical tube, two methods are usually used: one is to install a guide core rod at the center of the rotor to keep the rotor moving up and down on the centerline of the conical tube, and the other is to open inclined slots at the edge of the rotor disk. When the fluid flows through the rotor from bottom to top, it bypasses the rotor while passing through the inclined slots to generate reverse thrust, causing the rotor to continuously rotate around the centerline, thus keeping the rotor from touching the pipe wall during operation. The rotor material of the rotor flowmeter can be made of stainless steel, aluminum, bronze, etc.

Working principle of float flowmeter

When the measured medium flows through the measuring tube from bottom to top, a differential pressure is generated at the upper and lower ends of the float to form an upward force. When the upward force acting on the float is greater than the weight of the float immersed in the fluid, the float rises, and the annular gap area increases accordingly. The fluid velocity at the annular gap rapidly decreases, and the pressure drop between the upper and lower ends of the float is low. The upward force acting on the float decreases until the upward force is balanced with the weight of the float immersed in the fluid. The float stabilizes at the * position, and the height of the float position corresponds to the flow rate of the measured medium. The float is equipped with magnetic steel, and when the float moves up and down with the medium, the magnetic field changes with the movement of the float. By using a magnetic sensor to convert magnetic field changes into electrical signals, the instantaneous flow rate and cumulative flow rate are displayed and controlled through analog-to-digital conversion, digital filtering, temperature compensation, microprocessor processing, digital to analog conversion, liquid crystal display, and switch control output.

From the above, in essence, the working principle of the rotor flowmeter and the float flowmeter are the same, belonging to the same product, but with different names.