Sincerity, excellence in Coriolis flow meter production, since 1987  | 

Home  >  RESOURCE  >  News  > 

What should pay attention to the installation of mass flow meter

What should pay attention to the installation of mass flow meter

2022-07-12

Notes and summary of mass flow meter installation:


1. Since the mass flow meter relies on the Coriolis principle of vibration when the fluid flows through the pipeline to achieve the measurement purpose, the installation state of the gas mass flow meter should be a stress-free state, and the installation of the flowmeter should be on the same axis as the pipeline. Moreover, it should be supported near the mass flow meter sensor, and the sensor cannot be used to support the pipeline, which can eliminate vibration and reduce errors.


2. The selected installation site should be far away from large transformers or motors, because the cable connected between the sensor and the transmitter is covered or close to the electromagnetic field emitted by the motor, etc., which will cause interference, inaccurate readings and errors. In addition, different installation orientations should be selected according to the different properties of the fluid during installation, that is, the fluid in the sensor tube should always be kept in a full state.


3. Entrained air bubbles. When used for liquid flow measurement, when the content of mist gas exceeds 1% to 5% of the volume content, the mass flow meter will stop working. These bubbles damp the vibration of the flow tube used to generate the Coriolis force and should dissipate the gas before the sensor. If this is difficult to achieve, minimize the gas content (increase the pressure within the sensor as much as possible) to ensure that the bubbles are evenly dispersed into smaller bubbles (maintain a high liquid flow rate). Bubbles are created when the pressure of a liquid is lower than its vapor pressure. The pressure drop across the sensor caused by the geometry of the flow tube and the flow of the liquid can reduce the effective pressure of the liquid below its vapor pressure, and gas in the liquid in the pipe can have the same effect on the sensor as a fog bubble. Once the sensor is sized, the back pressure required to maintain the liquid state can be calculated. Install the sensor in a location that can meet the required back pressure.


4. Sediment and suspended matter. Thermal gas mass flow meters can calculate the mass content of one component in a solution or slurry of two components. Accurate density measurement needs to be avoided: sediments adhering to the measuring tube wall or solid particles settling out of the suspension (flow rate too low).


5. Vibration. The introduction of the double-pipe design greatly reduces but does not completely eliminate the effect of common mode vibration on the coriolis mass flow meter. External vibrations introduced by the pipeline system can cause undesired vibration patterns of the sensor. If the external vibration frequency is equal to or close to the frequency of the sensor drive system, it will interfere with the drive control system of the instrument, causing the flow tube to vibrate unstable or stop vibrating.

6. Hazardous location installations. If you want to install the instrument in an explosive place, you must first pay attention to whether the instrument is an intrinsically safe instrument, and determine whether it is allowed to be installed according to the on-site explosion-proof level requirements and the instrument's immediate certification documents. In the process of installation, the influence of ambient temperature on related components such as sensors, transmitters, and cables should also be considered. Consider waterproofing when installing outdoors, and consider the length of the special cable for the split-type mass flow meter (refer to the corresponding product manual for details).


7. The flow field is based on the principle of step by step. In principle, the Coriolis flow meter is not affected by the flow field distribution, and does not require front and rear straight pipe sections. In actual field applications, not all types of flowmeters are not affected by the flow field distribution. Although the Coriolis force mass flowmeter does not have high requirements for the flow field distribution, for the double vibrating tube type Coriolis force mass flowmeter, when the flow field changes too drastically, it may cause inaccurate measurement.


8. Other notes.


In addition to the above points to be considered, the following principles should also be followed when choosing an installation site: when using a Coriolis mass flow meter price to measure liquid media, especially easily vaporized liquids or liquid media containing a small amount of gas, The flow sensor should be installed at the lower part of the pipeline, not at the higher part of the pipeline to prevent the inclusion of gas from accumulating in the measuring tube and causing measurement errors; when using the Coriolis mass flow meter side face For gaseous media, especially non-dry gas or gaseous media that is easy to liquefy under high pressure, the flow sensor should be installed at the higher part of the pipeline, not at the lower part of the pipeline, so as to avoid the accumulation of liquid in the measuring tube. The accuracy of image measurement.


In addition, if conditions permit, the convenience of mass flow meter installation, routine maintenance and disassembly should also be considered. For example, install the flow meter downstream of the steam purge line, and be careful not to install the sensor too high or in a place with many and complicated surrounding lines. These practices will provide convenience for the installation and routine maintenance of the flowmeter.


Chat Online
Chat Online
Chat Online inputting...
Sign in with: