With the vacuum material extraction method, is it possible to remove a specific section with relatively high precision?
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This post was last edited by devo on 2019-3-27 00:58. If it’s driven by pump pressure, just add a tee valve – it’s very simple! But is there a way to perform vacuum extraction? Here is a schematic of my requirements: 1. Under normal conditions, the powder material is transported from its source in the direction of A, and this is achieved through vacuum suction ； 2. Under certain special circumstances, it is necessary to switch the material in direction B at point c using a certain valve ； 3. The switching speed should be as fast as possible. I’m not an expert, but I’ve heard that it might need at least 0.2 seconds; 0.2 seconds should be sufficient for now, but we’ll leave that aside for the time being ； 4. After being transported to B, this material is stored in storage tank D and is not sent to any other location ； I don’t understand whether it’s necessary to have the same vacuuming equipment installed at both A and B simultaneously There is a very special situation here: 99.9% of the time, the materials flow toward A, and only in very rare cases is it necessary to direct the materials to B for storage. Therefore, it is not reasonable to invest in equipment for both A and B at the same time. So, can it be achieved in direction B using a vacuum tank? And once this tank drops below a certain pressure, does device A create negative pressure in it again? After all, B is used very little, so there’s almost certainly enough time! Thank you so much!
For vacuum pumping, this refers to negative pressure; it depends on the pressure in your pipelines, as well as the temperature. If these values are relatively high, then it’s necessary to use specialized vacuum ball valves, vacuum butterfly valves, vacuum diaphragm valves, etc
The negative pressure shouldn’t be high; it’s just used to draw out some powder, with a density similar to that of flour – perhaps slightly higher than that of flour! Pipes are generally made of translucent plastic pipes with metal spiral wires inside. There are mainly two issues I want to address now: 1. Is there any way to measure the flow rate of the powder inside, and it needs to be measured in real time; 5 updates per second should be sufficient ； 2. A certain type of valve is installed in the middle of the vacuum pipeline; under normal conditions, the powder is transported in a straight line. When a control signal is received under special circumstances, the valve activates, immediately changing the direction of the powder flow to a branch path, while the original path should be closed simultaneously. A response time of 0.1 seconds should be sufficient! Have you used any similar applications before? Do you have any suggestions?
Let me answer the second point for you! The second issue is easy to resolve by using a three-way valve, a T-shaped three-way valve that changes from a straight-through design to a curved one. As for the response time, it is 0.1 seconds; this depends on the diameter of the valve. For pneumatic three-way valves, this is the case. If the diameter is small, below DN50, the switching time is around 0.2–0.4 seconds. In the case of larger diameters, one can only install a quick exhaust valve to try and reduce the time, but it’s only a relative reduction!
For vacuum split conveying, a three-way ball valve will suffice.
The valve you’re referring to for changing direction is the three-way directional valve used in pneumatic conveying, also known as a Y-type directional valve; it has a small angle of incidence, resulting in low flow resistance. Conventional vertical three-way ball valves won’t work. Or, a wear-resistant ball valve can be installed on each of the two pipes that change direction, one for opening and one for closing. Which company are you from?
Speed shouldn’t be a big problem! I have added to my question. What confuses me is how to route the material through the three-way valve – is it a device that applies vacuum in both directions? Please refer to the additional notes and diagrams I’ve provided on the first floor. Thank you so much!
Please see the addition to my question on the first floor. I’m confused about what force is used to switch it over; the valve’s operation is quite simple, but after all the entire system relies on vacuum extraction. Are identical vacuum extraction devices used in both directions? But the cost is not appropriate, because the other direction only works in extremely special situations – that is, the valve operates very rarely! Thank you so much! I just registered, and the forum administrator here has already warned me not to share contact information. I’m worried that he might ban me from posting. :) This forum seems to have a bug; it crashes as soon as I upload an image. Ugh!
It is recommended to use positive pressure conveying + directional control valve, as it is easy to implement.