Pump Curves

[hanksmith]

Can anyone tell me if there are curves that show the starting of a pump?

I would like to know how long it is going to take for a certian pump to start based on being connected to a motor, so far the manufacturer has just given me motor information which has nothing to do with how long it is going to take for this pump to get up to running speed and I don't know if I should keep bugging them for this information if it does not exist.

Thanks

 

[dabluffrat]

For an induction motor it should not take more then 3-4 seconds at most, synchronous motors will depend on the power factor setting in the filed current exciter. Ask the pump mfg for a torque speed curve for the pump and analyze your starting conditions; starting against closed valve (torque at shut-off) or starting with empty pipe (starting at run-out)

Did you know that 76.4% of all statistics are made up...

 

[hanksmith]

Thanks Dabluffrat

It will be an induction motor,

The pump in question is a vacuum pump so I would assume it's considered starting at run-out.

I am currently contacting the sales rep to see if he can get me a speed-torque curve.

May have more questions if I ever get this curve.

 

[dabluffrat]

the motor mfg should tell you the starting torque available in the motor, then make sure the starting conditions of the pump (pump torque at start) do not exceed the motor's rating.

Did you know that 76.4% of all statistics are made up...

 

[BigInch]

I've been dying to ask for a long time now. Is that statistic one of them?

**********************
"Pumping accounts for 20% of the world’s energy used by electric motors and 25-50% of the total electrical energy usage in certain industrial facilities."-DOE statistic (Note: Make that 99% for pipeline companies)

http://virtualpipeline.spaces.live.com/

 

[dabluffrat]

Big,

Using the online gospel, AKA Google Search, on "76.4% of all statistics are made up" proves this stat is spot on =)

Did you know that 76.4% of all statistics are made up...

 

[BigInch]

do you think my byline statistic is made up?

**********************
"Pumping accounts for 20% of the world’s energy used by electric motors and 25-50% of the total electrical energy usage in certain industrial facilities."-DOE statistic (Note: Make that 99% for pipeline companies)

http://virtualpipeline.spaces.live.com/

 

[BigInch]

hank,

What motor size is this. Is it a NEMA standard frame size?


**********************
"Pumping accounts for 20% of the world’s energy used by electric motors and 25-50% of the total electrical energy usage in certain industrial facilities."-DOE statistic (Note: Make that 99% for pipeline companies)

http://virtualpipeline.spaces.live.com/

 

[Artisi]

Is your vacuum pump a rotary unit? have attached a centrifugal pump speed curve, I would assume it is the same for a rotary vacuum pump.

 

[dabluffrat]

No, it sounds about right, but then again most stats do w/o research... i do know that pumps are the 2nd most mfg product in the world behind electric motors, so a stat linking them together makes sense.

Did you know that 76.4% of all statistics are made up...