5
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Accepted
Transfer pump suitable for air, water and their mixture
The terms you are looking for are "self priming pump" and/or "run dry pump".
Centrifugal self priming pumps require some water to be in them to start, but can pull a vacuum including air.
Diaphragm ...
- 8,226
4
votes
Accepted
deep vacuum in the 19th century
Geissler invented the so-called "liquid piston" pump using mercury for the piston. The basic idea of the design is to entrap some of the air between two volumes of mercury in a pipe, and then force ...
- 12.5k
3
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Are vacuum actuated artificial muscles as hard to control as the pneumatic ones?
With a vacuum you are limited to the pressure differential between zero and atmospheric (~100kPa or ~15PSI). With pneumatic you are limited to the pressure differential between atmospheric and ...
- 5,621
3
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Inlet/outlet of a fridge compressor
The small tube I believe is for the freezer coil, or it could be a capillary tube (thank you Swift). Regardless, simply solder it shut and use the two larger lines for pumping.
I would like to note, ...
- 716
3
votes
How to regulate a vacuum pump?
The device you're looking for is called a vacuum regulator and sits between the vacuum source and the process. This page from Equilibar shows some examples and provides links that explain how they ...
- 2,145
2
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What kind of solenoid valve should I use for vacuum?
A pilot operated valve (often unfortunately generalized as a "solenoid valve") uses a small control solenoid valve and the pressure differential across the valve to open a diaphragm that ...
- 8,226
2
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Vacuum Pump Specs
Evacuating 10 psi of pressure from a 500 cu ft chamber in under a second is pretty insane. This is a good calculator, as you will probably need to change your parameters (most likely time) in order to ...
- 2,347
2
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How do vacuum sealers work on a glass jar?
What they are doing in the video is heating up the liquid inside the vessel, (with an open lid).
Then they take it out and immediately (i.e. before it cools down), they pack the lid.
What happens is ...
- 24.2k
2
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How do vacuum sealers work on a glass jar?
Not checked out the video, but if you put a jar with a liftable lid in a vacuum sealer then as the pressure outside the jar is reduced air in the jar will push past the seal to equalize the pressure.
...
- 15.9k
2
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What is the maximum vacuum level achievable from heating up a metal in a vacuum chamber full of oxygen?
(The device concept you're describing is called a getter.)
The thermodynamic aspect is addressed in Ellingham diagrams:
You place a straightedge on point "O" (for oxygen) and on the ...
- 1,610
2
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Vacuum vessel at 10mbar with a diaphragm pump: do I need a venting valve?
I am not a vacuum expert, but if you look at the technical data for your pump, you'll find this "Leak rate 6x10-3 Pa m³/s". I take this to mean that your 10 liter = 0.01 m$^3$ vessel will leak at a ...
- 2,656
1
vote
Accepted
Can I use a standard HVAC rotary vane vacuum pump to draw a vacuum on a sealed chamber?
I have the same pump and I use it to hold (no flow) vacuum without any problems (my use case is to hold vacuum while in epoxy mixture so that all bubbles can be extracted before pouring it into the ...
1
vote
How do vacuum sealers work on a glass jar?
They heat the jars and take them out of the oven open the lid to let the pressure out and then close it.
Once the jar gets cooler the pressure inside that was occupied with hot expanded air settles ...
- 22.6k
1
vote
Is there a good way to passively dry air in the input of a vacuum pump?
The standard is a cold trap. Use anything from ice to liquid nitrogen depending on how dry you want it to be. Dry ice ( CO2) and acetone is very cold and fairly easy to get.
- 6,172
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Is there a good way to passively dry air in the input of a vacuum pump?
You can heat the air. As long as the temperature of the air remains above the dew point at all time, no condensation will occur in the compressor. The dew point is a function of absolute vapor ...
- 4,781
1
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Balancing suction air flow at different areas on pipe
I would suggest separate channels to each set of holes with orifice plates to limit the flow to / from each.
That way you can control each set individually.
The other solution will be to over-specify ...
- 15.9k
1
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Balancing suction air flow at different areas on pipe
It will be a next to impossible task to try and analytically predict the number/position/size of the holes in order to have exactly the same flow.
Even if you do for a temperature and a set humidity, ...
- 24.2k
1
vote
How can I make a vacuum pump to move rocks from one place to another?
What you are seeing in the video is a vacuum generator/vacuum ejector/aspirator.
Figure 1: Venturi effect (source: wikipedia)
It uses the principle of the Venturi effect. I.e. that for steady, ...
- 24.2k
1
vote
Accepted
How do I increase negative air pressure without inhibiting airflow?
I'm not sure what the first paragraph was about (pickup tool?), but if the vacuum reserve is installed like you have drawn it, there will be no appreciable loss of airflow when the solenoid is open. ...
- 7,013
1
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Vacuum Pump Issues
eatscrayons suggestion for leak detection is great. However, instead of acetone, I would use isopropyl alcohol (or even better, a helium gas source since He is such a small molecule).
It is ...
- 140
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Vacuum Pump Issues
6 Torr isn't too bad really and that vacuum pump looks a bit small and I am guessing is not a high quality unit? Also, as said in the comments, that water valve may be leaking as well as it isn't ...
- 716
1
vote
Accepted
What is the formula to work out time to remove water from an open vessel with vacuum?
So if your fan doesn't produce a minimum of 1m of water (which is about 2.9 inHg), there would be no flow. Afterwards, it depends upon your fan curve. You would find that the system curve would ...
- 5,333
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Arduino CNC - which vacuum pump?
I would recommend a slightly less technical approach and use double sided sticky tape. It's wonderful stuff, and you can get what's called removable tape. Probably makes it a bit easier, but you ...
- 916
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Vacuum vessel at 10mbar with a diaphragm pump: do I need a venting valve?
You will likely want more than just a vent valve - to avoid contamination of a vacuum chamber, typically you re-pressurize with an inert gas like nitrogen to avoid sucking condensates and water vapor ...
- 407
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