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5 votes

What is this plumbing apparatus?

it has to be water for fire because its red. its on the out side so they can control the water without going into the building. the open pipe is to drain the water for maintenance. it does not have a ...
joe's user avatar
  • 51
4 votes
Accepted

Divide Flow and Maintain Pressure

Short answer: I suspect that so long as your pump is a positive displacement pump (ex: the "vibratory pump" or "rotary vane pump" as described in this webpage about espresso pumps) and is sized to ...
baltakatei's user avatar
3 votes

Decoding pump- valve analogy for medical instrument

My first guess for any medical pump is a peristaltic pump, as they can pump one fluid then another without contamination (by swapping lines). Couple this with the fact that they can also be multi-...
Chuck's user avatar
  • 3,565
3 votes

Valve first,then heat exchanger OR heat exchanger first then valve

I think the key information is that the liquid is saturated. This means any reduction in pressure will lead to partial vaporization and two phase flow. For heat tranfer best overall heat transfer ...
Ohio ChemE's user avatar
3 votes
Accepted

Can PWM be used to control the flow of a solenoid valve?

It is possible to modulate the drive of some types of solenoid fluid valves to ultimately regulate the pressure of the fluid at their output port. I have designed a product that does excatly that. ...
Olin Lathrop's user avatar
  • 11.4k
3 votes
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Is there a (sort of inverse security) valve which opens if one connected side has a pressure below a certain value?

You're looking for a pressure regulator (and this is indeed what you need in your use case, but that is another question.) The regulator works so that over a range of flows, the pressure on the outlet ...
mart's user avatar
  • 4,791
3 votes

Check valve with precise cracking pressure

Check Valves are available with adjustable cracking pressures, using a preload spring to control the poppet force, for example: http://www.my-ssp-usa.com/products/valves/check-valves/adjustable-cpa ...
Jonathan R Swift's user avatar
3 votes
Accepted

How to inflate or deflate a bouncy ball that lacks a standard valve?

Yes, normally you can pull those plugs out - takes a strong grip or « folding » the ball to be able to push on the inner end of the plug... Here is a photo with such a plug taken out:
Solar Mike's user avatar
  • 15.9k
3 votes
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Improving O-Ring/flapper valve injection mold ->non-engineer

This community is not dead, but it is assuredly populated by people (like me) who make a living by being paid to solve problems exactly like yours. Now, it is common for small design and manufacturing ...
niels nielsen's user avatar
3 votes

What does 12CC refer to when talking about voltage?

Italian "corrente continua" is Direct Current.
elchambro's user avatar
  • 131
2 votes

Is there and easy way to go from 1000 psi to 45 psi without a complicated pressure regulator

As far as engineering systems go, it doesn't get much simpler that a pressure regulator; single or double. The mechanical feedback is solid solution. Wiki link for pressure regulator operation (for ...
ericnutsch's user avatar
  • 8,181
2 votes

Which components to use for a CO2 gas storage?

Your option 1, done "according to specs": Two check valves and a pressure regulator with separate output and regulation input (these are usually joint; output pressure being the regulating/feedback ...
SF.'s user avatar
  • 6,105
2 votes
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Liquid vs. gas check valves

No, liquid check valves function on density, viscosity or velocity or a combination and the mass is taken into account - gas check valves are designed to deal with a fluid 700 or more times less dense ...
Solar Mike's user avatar
  • 15.9k
2 votes

Automatic siphon above max height

I think you can create a self-starting siphon if you are able to add pipe to both ends of the "drain pipe." You'd extend the output end downwards until the exit of the pipe is below the bottom level ...
Carl Witthoft's user avatar
2 votes

Deflection of a stack of disks under applied force/pressure

Between disc 1 & 2, there is a reaction force on disc 1 which is not going to act on the edge rather at the distance of 2nd disc edges. This means you need to have the model of 1st disc bending ...
Nagarajan's user avatar
2 votes
Accepted

Is there a male and female valve that is closed until connected together?

There are many, many different commercially-available designs of fluid connectors that shut off automatically when disconnected and open up when connected. They are available in plastic and metal, ...
niels nielsen's user avatar
2 votes

How to periodically shut down a recirculating hot water solar thermal system

I would not mess around like this at all. I would make a secondary heat dump (old radiator in the garden, swimming pool...) and divert excess heat there.
Solar Mike's user avatar
  • 15.9k
2 votes

Is there a type of check valve that allows gas to flow in both direction but stops liquid from flowing back?

If the flow rate is low for the gas then a ball that floats on the liquid will work - similar to how most wet vacs stop liquid getting into the motor...
Solar Mike's user avatar
  • 15.9k
2 votes

Does it make sense to have a pressure and flow controller on a single closed line?

In addition to NMech's answer, the pressure regulator sets the maximum pressure that the system will see while the flow control limits the maximum flow that the downstream system will receive. This ...
Transistor's user avatar
  • 10.9k
2 votes

Can air flow occur in both directions in a 2 way solenoid valve?

A typical 2 way solenoid valve would not restrict airflow towards one direction. So in your case is perfectly valid, since you will be removing the pressure from the inlet. What you would normally do ...
NMech's user avatar
  • 24.4k
2 votes
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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 ...
ericnutsch's user avatar
  • 8,181
2 votes
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ELI5: How does this water (solenoid) valve work?

A fairly clear video explaining the operation of the valve is provided by Rain Bird Irrigation™. It shows how the inlet water is providing pressure against the diaphragm, sealing the exit opening. ...
fred_dot_u's user avatar
  • 7,227
2 votes

Confusing terminology for "normally closed/open" - It means the opposite in electronics (relays) versus fluids (valves)

It may help to think of the switch in terms of contact gap. A "closed" contact has no gap and conducts. An "open" contact has a gap and doesn't conduct. In the case of valves it ...
Transistor's user avatar
  • 10.9k
2 votes

Volume multiplying hydraulic pressure reduction unit?

You can use a motor / pump combination. There are motors and pumps that use the swash plate design and can vary pressure and flow from zero to max.
Solar Mike's user avatar
  • 15.9k
2 votes

Volume multiplying hydraulic pressure reduction unit?

Something to look into is hydraulic intensifiers, combining this with a pump would theoretically give what you desire.
Jack's user avatar
  • 21
2 votes

Volume multiplying hydraulic pressure reduction unit?

Most pressure reduction is adiabatic, no work is done. Expansion cools the fluid and ambient heat is absorbed. Certainly you can use high pressure fluid to do work to generate power, operate a shaft, ...
Tiger Guy's user avatar
  • 6,969
1 vote

Valve first,then heat exchanger OR heat exchanger first then valve

Lower pressure heat exchanger is going to be easier to build, but will also need a larger surface area because the heat transfer coefficient is higher for compressed fluids. I suggest trying to ...
Gunchars's user avatar
  • 151
1 vote

Can PWM be used to control the flow of a solenoid valve?

Yes, you can control flow/pressure with an on/off solenoid, using electronic PWM. EPRs such as these from SMC do exactly that. The lifetime of the valves in # of cycles needs to be considered, as well ...
River Weiss's user avatar
1 vote

How to find the balance position of valve downstream a tank?

This post is a little dated but thought someone might benefit from another angle. @Solar Mike is correct. The reason you overflow frequently is because your exit valve is undersized for in inlet ...
FredG's user avatar
  • 11
1 vote
Accepted

Can I make check valve in simple workshop?

Figure 1. A sprung check-valve using a ball and a taper. Source: Cross Controls I'm no machinist but it seems to me that a purchased ball (a bearing, for example) should make a good fit into a well ...
Transistor's user avatar
  • 10.9k

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