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How bad is the water vapor in the gas mass flow controller?

A water treatment plant in a certain area neutralizes chlorine by precisely injecting ammonia gas into its water system, thereby guaranteeing an average of 60 million gallons (approximately 227 million liters) of drinking water per day. However, the thermal principle of the mass flow controller (non-Ericart products) originally used in the factory caused damage to the thermal sensor due to the infiltration of liquid ammonia. The sensor in the conventional thermal mass flow controller is set to increase the gas temperature to a specified range when the gas passes through. Because the liquid has a higher thermal conductivity than the gas, even a momentary, trace amount of liquid appears in the gas path. It will quickly cool internal components. When a drop in temperature is detected, the temperature regulator consumes more power to heat it to the prescribed temperature, causing the electronic component to burn out quickly.
There are many reasons for inadvertent liquid infiltration in the mass flow controller. For example, environmental monitoring stations need to monitor the air quality under various weather conditions. It is possible that rain, frost, and snow melting can cause water vapor to enter the mass flow controller. Fuel cell applications generate water by mixing oxygen and hydrogen. Easily introduce water vapor in the middle; or the liquid tank used for gas injection has returned.
Solution
If the inside of the Erikat Mass Flow Controller seeps into water vapor, the situation is not that bad. Different from the thermal principle, the Airicat mass flowmeter and mass flow controller use laminar flow differential pressure technology, relying on the patented laminar flow structure to convert gas from turbulent flow to laminar flow, by measuring the gas pressure at both ends of the laminar flow sheet. Poor way to measure flow.
The above-mentioned water treatment plant could not bear to purchase a batch of new mass flow controllers after each infiltration of water vapor, and Zui finally replaced all the thermal principle instruments with Eric Carter. Now when the liquid ammonia enters into the mass flow meter or the mass flow controller again, simply rinsing the line with high-pressure ammonia gas can be followed by disinfection.
Discharge liquid
If your Erikat mass flow meter or mass flow controller is infiltrated with liquid substances, do not ignore it. If the liquid stays in the gas path for too long, it may cause different metals to react with each other. If possible, place the equipment under vacuum conditions. High vacuum (0.25 psi or less) plus micro-heat (50 to 60 °C) will allow the liquid to evaporate from the tiny air channels inside the equipment.
If the liquid contains suspended particulates, the dehumidification process may leave solid particles, resulting in residues in the mass flow meter or mass flow controller. The residue is too heavy to interfere with the laminar motion of the gas and there is little chance of affecting the measurement accuracy. However, if so, isopropyl alcohol must be used to clean the equipment. Erickart's after-sales service engineers will disassemble, clean, and recalibrate the device.
If your mass flow controller is a corrosion resistant series of 316L stainless steel, you can sit back and relax, because the structure of the corrosion resistant series is basically the same as the liquid flow meter and the liquid flow controller, allowing the liquid to infiltrate to a large extent. [At this point you may ask: Does Eric Carter also have liquid flow meters and liquid flow controllers? ]
Some customers, such as the above-mentioned water treatment plants and ambient air monitoring stations, abandoned the common thermal principle equipment and switched to Erica’s laminar differential pressure mass flowmeters and mass flow. The controller thus personally learned one of the many little-known advantages of Eric Carter equipment. If you happen to be dealing with tricky, challenging flow or pressure related projects, then this is definitely a good reason to choose the Ericcat mass flow meter, mass flow controller.

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