The principle of metal tube rotor flowmeter is consistent with that of glass rotor flowmeter, with variable area measurement principle. It has stable performance, complete functions, easy operation, and is safer to use than glass rotor flowmeter. It is mainly used to measure liquids and gases. The quality of the metal tube rotor flowmeter is determined by the manufacturer, but the quality of its use depends on installation, correct use, and normal maintenance.
In order to ensure the normal operation of the metal tube rotor flowmeter and achieve the required measurement accuracy, the following points should generally be noted:
1. The outlet should have a 250mm straight pipe section, and the inlet of the metal tube rotor flowmeter should have a straight pipe section of at least 5 times the diameter of the pipe. To ensure the accuracy of instrument measurement;
2. When the fluid flows from bottom to top of the flowmeter, the metal tube rotor flowmeter must be installed vertically. And the verticality should be better than 2 °, and the horizontal angle should be better than 2 ° when installed horizontally, so as not to affect production during troubleshooting or blowing; The metal tube rotor flowmeter installed on the process pipeline should be equipped with a bypass.
3. If the medium contains solid impurities and ferromagnetic substances, it should be considered to install a filter between the valve and the straight pipe section;
4. When insulation protection measures need to be taken, if the temperature of the measured medium is higher than 220 ℃ or the fluid temperature is too low, crystallization may occur. A jacket type should be selected for cooling or insulation purposes;
5. The instrument for measuring gas should ensure that the pipeline pressure is not less than 5 times the pressure loss of the flowmeter to ensure stable operation of the float. Calibrated under a certain pressure, if the gas is directly discharged into the atmosphere at the outlet of the instrument,. It will generate a pressure drop at the float and cause data distortion. If such working conditions are met, a valve should be installed at the outlet of the instrument.
6. Metal tube rotor flow meters generally do not require maintenance after normal operation of the device. Malfunctions often occur when the device is just started, and due to poor pipeline cleaning, the float is stuck by solid particles, causing the indicator pointer to stop at the same position. At this point, first close the valves on both sides of the flowmeter, then remove the upper flange, take out the float for cleaning, and reinstall it. Pay attention to tightening the flange nuts evenly and place washers on them.