Regarding the weighing issue of liquid leaking out of a container
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This post was last edited by yiy on 2017-10-18 at 10:32. Dear teachers, I have a question. We have an application that releases a certain amount of liquid from a container. My idea is to use a weighing module to record the weight before discharge and the weight after discharge, and use this difference to control the opening and closing of the valve. There are two questions now: 1. Is this approach feasible? 2. For the pipeline for the flowing liquid, whether to use a hose or a rigid pipe, and how to connect it to the container so as not to affect weighing. The simple solution is shown in the picture. Thank you
That method will affect the weighing, it’s just a matter of how much the impact is
Is the flow rate constant each time? Regarding takeover, it’s obviously a soft connection; then you need to consider whether your materials are corrosive, as well as the temperature and pressure
Thank you for your reply. Will the liquid in the hose affect the weighing? What I mean is the liquid that has flowed out of the container but is still in the pipeline – will this be included in the weight reading?
The idea is feasible; it essentially involves controlling the mass flow rate. One could consider using a Coriolis flow meter – when using Coriolis technology for mass measurement, the liquid in the pipeline has no impact~~
When working with pipes, the flexible connections are installed horizontally, while the feed pipes or drip pipes are installed vertically. The material inside those pipes should still be in the weighing section; what shows as a decrease is the net weight. It’s not clear what exact error tolerance you require. When choosing a weighing system, it is recommended to use four modules: one fixed type, one fully floating type, and two semi-floating types. A three-module system seems to be of relatively lower quality
A flexible connection is better, but the weighing conditions must be the same both times; this way, the error can be relatively small.
Why must it be heavy? Is the liquid level not okay?
From your diagram, it appears to be a control valve. A simple automated solution for controlling the amount of material added is as follows: a fixed amount of X kg of material is added to the metering tank. There are several options: 1. Weighing system + control valve (fast operation due to pneumatic action); 2. Mass flow meter + control valve (fast operation due to pneumatic action); 3. Level gauge (single or double flange type, magnetic flap type, radar type, magnetic float type, etc.), but since density is affected by temperature, this method is less accurate than using mass measurement + control valve. A simple automated modification for feeding at a constant speed until the desired amount has been added: a mass flow meter + control valve (pneumatic valves are used in explosion-proof areas; the valve opening level is memoryable, which makes it easier to implement complex interlocks and achieve overall automation in design and operation); this scale plus control valve can also be used for this purpose.
It should be feasible. The degree of precision depends on what kind of liquid it is. If the price isn’t high, it can be rougher. Or use level control.