At the oil dispensing station, before the oil flows out through the dip pipe, does it flow through the electro-hydraulic valve first, or through the flow meter first? Please ask those with experience for guidance
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At the oil dispensing station, before the oil flows out through the dip pipe, does it flow through the electro-hydraulic valve first, or through the flow meter first? I would appreciate advice from those with experience. When I look at the diagrams, I’ve seen both scenarios – which one is better? Why?
It is best to pass through the flow meter first, as this ensures a more stable flow rate, which contributes to greater accuracy in measurement； Furthermore, if possible, it is best to add a straight pipe section with a diameter at least 10 times that of the flow meter in front of it. If a solenoid valve is placed in front of the flow meter, changing laminar flow to turbulent flow will increase the region of instability in the flow meter! ! ! For reference only! ! ! ! :handshake :victory: Last edited by aymzj on 2009-3-4 09:35 in this post ]
My designs are all like this; the factors taken into consideration are the same as those for the second floor. Flow meters require straight pipe sections
I would like to ask, what kind of pump is generally used for applying hair serum? Is it a centrifugal pump? Is it available with a positive displacement pump? Is this straight pipe section still needed if a positive displacement pump is used? Also, the 10-times straight pipe section is quite long; what should be done if there isn’t enough space at the oil distribution point? Please give some advice!
It is not necessary to place the pump under the fuel dispensing station; as for the selection of the pump used for fuel dispensing, it is determined primarily based on the properties of the medium. To supplement what was said on the second floor, the requirements for the straight pipe sections ahead of and behind a flow meter are highly dependent on the type of flow meter; certain types require five straight pipe sections in front and three behind them.
Since the valve needs to be shut off in multiple stages, it is generally placed after the flow meter.
It’s best to go through the flow meter first, I agree! However, whether a straight pipe section with a diameter 10 times larger is necessary can be determined based on your conveying system. The installation location of the flow meter can be moved.
If it passes through the valve first, it makes it difficult to measure for the next operation. Moreover, opening and closing the valve has a certain impact on the flow meter (when a pump is present).
10 times is a bit too long; it’s difficult to arrange space for it.
It is best to pass through the flow meter first and then the solenoid valve; this makes it easier to control and improves the accuracy of measurement.
Personally, I think the solenoid valve should be placed first; since flow meters often need to be serviced and calibrated, it is easier to remove them after the valve for handling, mainly with regard to dealing with liquid accumulation inside the pipes. In engineering, isolation valves are generally installed before and after the flow meter.
Generally, the flow meter comes first, followed by the automatic valve. This can effectively prevent the impact of turbulence caused during the opening and closing of the valve on the accuracy of the flow meter. As for whether a 10-fold straight pipe section is required, it depends on the specific type of flow meter. The flow meters I have in the company don’t have such long straight sections, but their accuracy is still good.
Let the flow pass through the flow meter first; this ensures a more stable flow rate, which is beneficial for accurate measurement. It is advisable to install another ball valve behind the electro-hydraulic valve as well, as this facilitates operation.
The requirements for straight pipe sections depend on the specifications of the flow meter itself. Mass flow meters do not require any straight pipe sections, but volumetric flow meters do; however, these requirements are related to changes in the diameter of the process pipeline before the flow meter is installed. Changes from larger to smaller diameters, or from smaller to larger diameters, all result in different requirements for straight pipe sections.
From the perspective of accurate measurement, it first passes through a flow meter. Under normal conditions, the valves in the loading area, except for solenoid valves, are normally open and can be considered as straight pipe sections.
A straight section with a diameter 5 times that of the pipe is sufficient. The electro-hydraulic valve should be placed after the flow meter; I agree with the view from the second floor – this prevents the installation of the electro-hydraulic valve from altering the flow pattern of the fluid, thereby affecting the accuracy of flow measurement.
The electro-hydraulic valve is at the back, so the flow meter can give accurate readings
I agree with what the brother on floor 11 said; we cannot ignore the issue of maintenance. As for the requirements for straight sections, they depend on the installation requirements of the flow meter you choose – there is no one-size-fits-all solution!!