Is the selection of a metal rotor flowmeter related to pressure?
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Hello everyone, I purchased several sets of metal rotameters with DN80 sizes and PTFE lining, intended for measuring gases. The specifications were set based on a density of 3 KG per cubic meter, a pressure of 0.5 kilograms, and a maximum flow rate of 600 cubic meters per hour (the manufacturer stated that this is the maximum flow rate possible for this diameter under such conditions). In fact, the pressure at the location where we install the flow meter is 1 kilogram. The manufacturer stated that with a pressure of 1 kilogram, the maximum flow rate that the flow meter can handle is 500 cubic meters per hour (the actual flow rate in our production is a little over 500 cubic meters per hour). To avoid the need for a diameter reduction so as to match the pipe diameter, we decided to use a DN80 diameter anyway. Also, to make the range usable, it was set at a pressure of 0.5 kilograms. So, I would like to ask everyone: in such a situation where the actual pressure is higher than the pressure specified at the time of manufacturing, with the flow rate and density remaining unchanged, how will the float or pointer change? Will it be positioned higher or lower compared to when the pressure is lower? We don’t need precision; just a trend indication will do. Will that work? The float won’t reach the very top, right?
The density of a gas is related to pressure; at different pressures, the maximum flow rate that can be measured varies.
The manufacturer’s specifications for Jinzhuan are based on a pressure of 0.5 KG; your actual pressure is 1 KG, and as the pressure increases, so does the density. If the flow rate remains unchanged and the gold transducer shows full scale, the actual flow rate should be lower. If it’s just a matter of looking at trends, there’s no problem as long as it doesn’t exceed the maximum value.
The measurement range of rotameters is closely related to density, and gas density is highly dependent on pressure. As pressure increases, density increases, and the range decreases.