What Are the Precautions for Using the Turbine Flow Meter?

To make the qualified turbine flow meter run normally, some precautions need to be paid attention to.

Ⅰ. The influence of the natural gas medium on turbine flow meter

1. In the actual use process, the turbine flow meter is often dirty, which will affect the rotation of the flow meter impeller. If it is not processed, the pulse output of the flow meter will be affected.

2. If the surface roughness of the inner wall of the meter and the upstream straight pipe section changes, it will cause the flow rate distribution to change. And the change will affect the accuracy and stability of the flowmeter. Different manufacturers of turbine flowmeter sensor sensitivity vary. In general, the dirty accumulation of small-diameter turbine flowmeters has a more severe impact, while the impact on the larger diameter is less.

Ⅱ. The influence of working conditions on the turbine flow meter

Due to the turbine inertia of the turbine flow meter, it is not suitable to be used on occasions with frequent flow fluctuations because the measurement accuracy will be lowered. At the same time, it is necessary to more accurately estimate the peak and valley values of the gas consumption and the pressure of the medium, and then determine the specifications of the flow meter correctly. According to the error characteristic curve of the turbine flow meter, we can know that the working flow range should be between 20%Qmax~80%Qmax. (Qmax is the maximum flow rate of the flow meter.)

When the measured medium flow rate is less than 20% Qmax of the selected flow meter, the flow rate of the medium fluid in the pipeline is slow and in a laminar flow condition. And the measurement linearity of the flow meter becomes worse, which is not good enough to achieve the measurement accuracy required by the user. When the medium flow rate is greater than 80% Qmax of the selected flow meter, the turbine speed will change quickly, and the wear of the reduction bearing and bracket will affect the service life of the turbine flow meter.

Ⅲ. The requirements of the turbine flow meter in the installation

1. The asymmetry of the fluid velocity distribution and vortex flow are important reasons that affect the measurement accuracy of the turbine flow meter. To remove flow asymmetry and vortex flow, the front end of the turbine flow meter should have a long enough straight pipe section.

2. The installation position of the turbine flow meter should not have intense mechanical vibration and severe electromagnetic interference.

3. When the turbine flow meter is installed, the gasket shall not protrude into the pipeline, and there shall be no obvious deviation between the flow meter and the pipeline axis. And there can't be installation stress.

Ⅳ. The requirements for a turbine flow meter with mechanical readings

For turbine flow meters with mechanical readings and correctors, in addition to copying the volume value of the standard condition, please compare the base meter reading with the flow rate on the corrector on time. Under normal circumstances, the difference between the two should not be very significant.

V. Disassembly requirements for turbine flow meter

When servicing the process piping, please remove the flowmeter first, and then wrap both ends of the flowmeter with a clean cloth to prevent dirt, iron filings, etc. from falling into the flowmeter to damage the turbine blades.

Ⅵ. The daily inspection of the turbine flow meter

To ensure that the turbine flowmeter can work properly for a long time, the staff should strengthen the operation of the instrument to check and monitor the impeller rotation. If the sound is abnormal, you should promptly remove and check the internal parts of the sensor. If the turbine bearing is severely worn or damaged vane, please repair and replace, and re-calibrate.

Ⅶ. Routine maintenance of turbine flow meter

For sensors with lubricating oil or cleaning fluid injection port, please fill the oil or cleaning fluid regularly as required to ensure good operation of the impeller. If the sensor is operated continuously without lubricant for a long time, it will cause fatal wear and tear. Increased damping will lead to slower operation, negative measurement results, and affect the service life.