How to improve the measurement accuracy of mass flow meters?
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If we need to measure 500 KG of material, the electric valve located in the pipeline before the flow meter closes off when the amount measured reaches 500 KG. However, due to inertia and the pipe’s internal diameter, a certain amount of material still passes through the pipeline at the moment the electric valve closes, which results in errors in the measurement accuracy. I would like to ask those with experience: what good strategies are there for improving the measurement accuracy of mass flow meters? Please share your insights. Thank you! !
Hehehe. This has absolutely nothing to do with the accuracy of the flow meter. The issue here is shutting the valve in advance when the value is less than 500, and determining the optimal point at which to do so. Try it dozens or even hundreds of times – congratulations, you’ve managed to do it to your satisfaction! Go, monkeys, give it your all! {:2_36:} {:2_32:} {:2_34:} {:2_43:} {:2_42:}
It’s not gold that’s being measured; why need such precision? Besides, when the valve is closed, there is little flow of the medium anyway; if such high standards are required, then cut off both the supply and the return at the same time ； If one isn’t giving up, the flow meter can keep running for a while – but how big of a wave can that create? Flowmeters also don’t have such high precision.
Choose a smaller pipe diameter, and use a ton barrel to accurately measure how much more time passes at the moment of shutdown When setting the shutdown time, simply subtract this amount; in other words, shut it down earlier. For example, add 1.5 kg each time, so you can set the shutdown time at 500 – 1.5 = 498.5.
This post was last edited by qugd on 2019-9-1 21:29. Isn’t this kind of problem just about batch control? Why not use a flow integrator with batch control for regulation? Additionally, when measuring 500 kg, it is very important to choose a mass flow meter with an appropriate range. If your pipeline diameter is large and the flow measurement range is wide, it’s basically unreliable to measure 500 kg. With such a small amount, a low-range pipeline is needed to achieve good results. It’s just like using a scale to weigh things: a large scale is needed for heavier amounts, while a small scale is suitable for lighter amounts. If it’s just process metering, using a mass flow meter is completely unnecessary.
The electric valve is replaced with a multi-stage valve or a control valve, which gradually closes as the weight approaches 500 kg; this improves accuracy and also helps to prevent water hammer, thus protecting the equipment.
If extremely high precision is required, temperature compensation can be attempted
Therefore, it is common to install a zero-leakage valve at the outlet of the flow meter to prevent any possibility of non-metering under low flow rates of the medium.
Your requirement is too high; try a few more times to find a balance point – for example, close the valve at 499.5
I’m not sure; I can check the relevant information. Back-and-forth spraying machine, spraying robot, automatic painting machine, painting production line, tunnel oven, UV curing machine, UV lamp tubes, UV equipment, UVLED curing device, photocuring machine, franchise for whole-brain education, franchise for memory training, children’s whole-brain development, franchise for whole-brain development, franchise for right-brain development, UV curing machine, industrial oven
I’ve heard that when flow measurement is approaching, reducing the flow rate can help minimize errors. I wonder if anyone has experienced this?