Looking for a Pump Curve

[meDave2]

I was given a part number by my field personnel and it is a bogus number. They did pull a pump operation point stamped on the pump, 1105 gpm at 130 ft of head. The electric motor is 50 hp running at 1775 rpm. Can I construct a pump curve from this data or select a similar pump curve? The system is pumping chilled water through a building and my analysis says that the piping system needs to be redesigned.

 

[BigInch]

If you don't have a pump curve, how could you do an analysis?

Maybe you could get a rough idea of a pump curve, BUT

Can you tell us the Manufacturer, model number ...
type of pump, inlet diameter, outlet diameter, IMPELLER size?
or at least post a picture?

Heck give us something to go on! We're really good, but definitely not magicians.



**********************
"Being GREEN isn't easy" ..Kermit

http://www.youtube.com/watch?v=hpiIWMWWVco

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

 

[meDave2]

To do a building piping analysis for the chilled water system I am given the minimum flow demand and pressure drop for each chiller. The field personnel gave me sketches of the piping runs and dimeters inside the building. With this information I put it into a piping analysis program and it computed a pressure requirement for the flow demand. I didn't write the program. It is a comercially avilable program. Like many systems I think it was just built or added on to and not designed. I didn't design this system.

The piping in the mechanical room is 8" diameter. The pressure drop across the pump is 40 psig. All of the pumps and flanges are covered with insulation. I can't take a camera into this building.

 

[BigInch]

So you want a default pump curve?

Start at (Q,H)= 1.25 * 130 and sketch a parabolic curve kinda flat at Q=0 then curving down from from there through your (1105,130) point.

Now face east, pray a lot and keep your fingers crossed.

**********************
"Being GREEN isn't easy" ..Kermit

http://www.youtube.com/watch?v=hpiIWMWWVco

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

 

[meDave2]

Thanks

 

[BigInch]

Amen.

**********************
"Being GREEN isn't easy" ..Kermit

http://www.youtube.com/watch?v=hpiIWMWWVco

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

 

[Artisi]

What makes you think that the pipework needs redesigning?

 

[MJCronin]

Lets see....

1150 gpm at 130....I get 36.3 liquid hp

Allowing for 0.7 efficency (and a little bit for the seal etc) I get about 53-55 bhp required.

The 75 hp motor seems about right.

Can you identify the pump vendor from the casing ?

Find the local pump vendor rep ask him questions (he probably knows all about this particular pump)

Otherwise get a pump curve from the equivalent configuration from a competitor and use that. You cant be too far off....

-MJC

 

[dabluffrat]

Was the pump operating point stamped on a nameplate?? possibly listing the manufacture... if that pump were to go down today and someone in your plant needed to order parts... where/who would they order them from? Then go to that company's website and start looking for curves.

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

 

[QualityTime]

Did you check if the building have a shop drawing or record of the pump? Who was the engineer who put the pump in? They might have records of the pump and/or specfications still in their files

 

[BigInch]

OP seems to have logged off.

"We have a leadership style that is too directive and doesn't listen sufficiently well. The top of the organisation doesn't listen sufficiently to what the bottom is saying." Tony Hayward CEO, BP

**********************
"Being GREEN isn't easy" ..Kermit

http://www.youtube.com/watch?v=hpiIWMWWVco

http://vir