Dismantling of Rosemount vortex flowmeter
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There’s a problem: with my 8800 vortex flowmeter, the flow rate doesn’t increase. The settings are correct, so I suspect the flow rate is too low； Is it due to the sensor? When is it necessary to change the K coefficient? Change the table header, table body, or sensor? Please explain. I encountered an issue where the flow measurement was too low; the settings seemed fine, but after replacing the sensor with a new one, everything worked properly, without any changes to the K coefficient!
It’s best not to change the K coefficient, and it’s also advisable not to replace the sensor by yourself, as that requires a torque wrench. To determine whether the sensor head is damaged, you can first check the trigger level ratio; if that doesn’t work, turn to the seller for assistance.
The k coefficients are all calibrated by the manufacturer at the time of production, so it’s not possible to change them arbitrarily. Replacing the sensor is relatively simple; the torque required is only slightly more than that needed by an adult. Once a new sensor is installed, the k coefficient actually changes, but by a small amount that is not noticeable.
What I mean is, is the K coefficient for sensing compatible with the gauge transmitter? If only the sensor head is changed and not the gauge, does the K coefficient need to be adjusted? Is there anything else that needs to be modified?
The k coefficient has no relation to the meter header; our company does not take the meter header into account during calibration. The k coefficient is only related to the elements located below the meter header. Even if you change the meter header, all that is needed is to re-enter the calibrated coefficient
Then, if I replace the sensor in this watch with a new one, what parameters need to be modified? Eventually, it reached a situation where there was actual traffic; the meter was working fine before but then no traffic was detected, and the parameters seemed to be okay. After I replaced the meter’s sensor, traffic was detected again. What parameters need to be changed?
It is determined through calibration whether each flow meter meets the accuracy requirements for measurement; this calibration yields a flow coefficient k, which remains consistent with the internal measuring components of the flow meter (with the flow meter sensor being the key component) throughout its valid service life. After this period expires, that is, once the calibration cycle is over, factors such as scaling on the walls of the measuring components and the sensor surface, increased wall roughness, and a decline in the long-term stability of the electronic components containing the sensor can all lead to measurement inaccuracies. In such cases, re-calibration is necessary to establish a new coefficient k that meets the required standards. This is why regular calibration is essential. It is incorrect to replace the flow meter sensor without authorization or to modify the coefficient k without permission; if a replacement of the sensor is indeed necessary, re-calibration must be carried out to set a new coefficient k that satisfies the requirements.
The answer is very comprehensive. To add, the transmitter has nothing to do with the K coefficient; it’s not required during calibration.
Is anyone working on vortex flowmeters upstairs? Emerson’s?
No, I’m just a user of flow meters; these are just common knowledge regarding their use.
It does not refer to a transmitter; it is a sensor (in this case, a flow sensor), and the two should not be confused.