What flow meter is used for measuring LPG, liquefied petroleum gas?
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What flow meter is used for measuring LPG, liquefied petroleum gas? Medium pressure: 10 KPa; temperature: around 26.5°C; flow rate: 45–450 Nm3/h; pipe diameter: 150 mm. The orifice plate cannot be used for measurement as it is not suitable for low flow rates. I wonder if any of my colleagues have encountered this situation? Use a turbine flowmeter? Are there any others?
It depends on your requirements for traffic accuracy. For flow measurement in online streams, orifice plates are commonly used; for example, they are employed for flow regulation and control in production processes. For measuring the flow rate at the inlet and outlet of a device, domestic mass flow meters can be used. If quality mass flow meters of foreign brands are selected for foreign trade calculations, weight measurement using a scale is still required in the end. If the flow rate is measured in standard cubic units, it is better to use a mass flow meter; otherwise, the flow meter will need additional instruments for temperature and pressure compensation, and investment in installation, maintenance, and calibration all become problematic.
Stopping by to learn a bit. At this pressure and temperature, LPG should be in a gaseous state, right? If the nominal size is changed to the operating condition value, does the pipe diameter become too large?
“If the nominal size is changed to the operating condition value, does the pipe diameter become too large? ”This one won’t. Because when converting between standard conditions and operating conditions, pressure is calculated based on absolute pressure; that is, the coefficient reflecting the effect of pressure is determined using the formula (local atmospheric pressure + gauge pressure of the medium) / standard atmospheric pressure. With a gauge pressure of 10 KPa, the calculated coefficient should be close to 1 ； The coefficient affected by temperature is calculated based on Kelvin temperature, that is, (273.15 + medium temperature) / standard temperature; with a medium temperature of 26.5, the calculated coefficient should also be close to 1. Therefore, the conversion of the standard-condition flow rate of 45–450 Nm3/h to the operating-condition flow rate results in little change.
This post was last edited by atkyb.com on 2018-4-27 08:15 :D. When converting between standard conditions and actual operating conditions, the calculation is done using standard atmospheric pressure divided by (local atmospheric pressure + gauge pressure of the medium); this results in a coefficient of around 1, with temperature having almost no impact in this case. But for 45–450 m3/h, with a diameter of 150, the flow velocity is 0.7–7 m/s; in that case, turbine vortex flow meters won’t work
You can try gas ultrasonic or thermal mass
The conditions given aren’t quite right, are they? Please check again – how is it possible for liquefied petroleum gas to remain in a liquid state under these pressure and temperature conditions?
Under this pressure, it should be in gaseous state; give a try with a thermal mass flow meter, maybe one from E+H
The units are all Nm3/h, so it must be in gaseous state. If it’s in liquid form, just indicate the mass flow rate directly. And with this temperature and pressure, there can’t be a liquid state, right?
Choose a temperature and pressure integrated gas ultrasonic flow meter of class 1.0 or an insert-type gas mass flow meter of class 1.0
Based on experience, a range of this kind (45–450 Nm3/h) is generally suited for rotameters.