1、 Over range operation: damage to float and sensor
Incorrect operation:
Actual traffic exceeds
float flow meterMaximum range (if using a DN15 flowmeter to measure the flow rate of a DN50 pipeline).
Long term operation below the minimum range (such as flow rate below 20% of the range).
consequence:
Over range: The float impacts the top of the cone tube, causing deformation of the float or rupture of the cone tube; The magnetic coupling sensor is damaged due to overload.
Low flow rate: The float cannot rise steadily, and the reading error increases (significant nonlinear error).
The correct approach:
When selecting, ensure that the normal flow rate is within the range of 50% -70% of the measuring range.
If the flow fluctuates greatly, choose a wide range model with a range ratio of ≥ 10:1.
2、 Neglecting temperature/pressure compensation: errors caused by density changes
Incorrect operation:
Temperature/pressure compensation was not performed when measuring gas (gas density varies significantly with temperature and pressure).
The lack of a condensing device during steam measurement resulted in deformation of the float due to high temperature.
consequence:
Gas: The deviation between the actual flow rate and the displayed value can reach ± 20% or more (if the temperature increases by 10 ℃, the density decreases by about 3.5%).
Steam: Float softening and sticking, scaling on the inner wall of the cone tube, measurement failure.
The correct approach:
Gas measurement: Choose an intelligent float flowmeter with temperature and pressure compensation, or manually adjust the density parameters.
Steam measurement: Install a condenser tank to condense the steam into a liquid state and measure it (or use a steam specific flow meter).