Max. flow rate?

[ginsoakedboy]

Is there a practical limit to the flow rate I can get through a 1"OD x 0.156"Wall tubing?

This tubing is intended to circulate coolant at 20 to 60 psi. The tubing length is proposed to be ~50 ft.

 

[Latexman]

One practical limit is the economic optimum. With increasing flow, at some point the long term cost of ownership (combines total installed cost, utilities, maintenance, etc.) becomes less if you use the next larger size tubing.

Good luck,
Latexman

 

[ginsoakedboy]

Thanks for the reply, Latexman. I agree with you on the economics. Even my process can use a larger size of tubing. However, I am constrained due to collapse pressure concerns.

What would a safe limit for flow rate in this situation may be considering the pump sizing etc.?

 

[vpl]

What is your fluid? If it's water, 10 gpm is frequently considered to be a maximum, with preferable being below that.



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[ginsoakedboy]

30% glycol solution in water ...

 

[ginsoakedboy]

Can I flow between 30-60 GPM? What is the downside to high flow rates like these?

Is there is a formula that will help me compute max flow rate through a given size of tubing?

Thanks

 

[mjpetrag]

waterhammer, accelerated erosion around pipe, fittings and valves, etc. etc.

with a flow of 60 GPM you might see velocities of around 50 ft/s, which is around 8x what it should normally stay around.

-Mike

 

[mjpetrag]

theoretically i dont believe there is a limit on maximum flow through a given pipe diameter, but you also have to take into account the increased pressure drop through the system as the diameter becomes smaller. You will need an exponentially bigger and more expensive pump to overcome friction losses.

the only other limit i can see is the sonic velocity of the fluid.

i dont understand your constraint on collapse pressure though...



-Mike

 

[ginsoakedboy]

I am proposing to route the tubing into a pressure vessel for heat transfer. The vessel will be pressurized to around 8000 psi. Therefore, any tubing I consider needs to withstand this collapse pressure.

 

[mjpetrag]

If your constraints are dependent on each other (flow rate & pressure), I would manifold off multiple 1" pipes from a larger pipe outside of the tank. That way you could keep your 1" pipe(s), maintain pressure through a header, and get a lower velocity of fluid.

The other option would be to use a cooling jacket around the vessel although that can get expensive depending on the vessel size.

-Mike

 

[quark]

30gpm with your tube size would create a pressure drop of 7.7 bar (113 psi) for 50ft length of pipe(ignoring all accessories). So, coolant inlet pressure should be more than this for circulation to happen. 30 and 60 psi are out of question.

 

[Artisi]

Think quark meant 30 and 60 gpm in above post - but to finish off the comment, 60 gpm will require in excess of 452 psi for flow to take place.

 

[quark]

Artisi,

OP indicated, in the first post, that he intends to circulate coolant at 20 to 60 psi.

 

[ginsoakedboy]

Assuming that there are hoses say 10 ft long connecting the inlet and outlet of the tubing to the pump and reservoir, does this mean that the pump has to put out around 500 psi to sustain flow at max flow rate (~10gpm)?

 

[ginsoakedboy]

Ack ... Please excuse the earlier post.

The pump output pressure should be more like 130 psi for 10 gpm.

 

[Artisi]

Quark, sorry for the mis-understanding, I was thinking about the OP's 3rd post - 30 -60 GPM

 

[ginsoakedboy]

Thank you to everyone who responded. By the way, I found these links that list the recommended max flow rates through different pipe sizes (don't know the credibility of the source):

http://www.dsginc.biz/documents/maxflow_chart.pdf

http://www.urbanfarmerstore.com/library/pdf/sprinklers/pipesize.pdf

 

[VikingUK]

Artisi, you state that 60 gpm will require in excess of 452 psi for flow to take place.
Can you tell me how you calculated this please ?