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What are some things to consider when pumping 5000' below sea level?

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Lovison

Mechanical
Jan 25, 2002
92
US
I'm used to pumping above sea level but I was called and asked a question what are some of the affects that would come into play at 5000' below sea level. In a mine.

Do you have to do anything special. Special pressure gauges? Motor problems to contend with or what?

Thanks
 
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Lovison

Do you mean to say you will be pumping up to the surface from 5000 feet or that you will be pumping at various elevations at the lower elevations.
More discriptive information is needed.
Fluid
rate (gpm)
pressure or head
....

pennpoint
 
can't see any problems - atmospheric pressure will only be 2 - 3 lb more than at the sea level (sorry don't have any tables to check exactly) - the pump will ok but you will need to make gauge corrections if you need any critical measurements.
If you were to submerge the pump 30 feet below water level - here the pressure on the pump would be much higher, would you be concerned ???

International College
Naresuan University
Phitsanulok
Thailand
 
My previous message regarding submerging a pump under water assumed you are talking about a Toyo submersible pump - seeing as how you email is at toyopump.com

International College
Naresuan University
Phitsanulok
Thailand
 
From what I've been told the pressure at -5000' will be about 15% higher than it would above sea level. I also found out from another source that the depth below sea level (not under water) will be the inverse of above sea level.

Also that the temperature below will increase (if not cooled) and that the bearing temperature ambient will be higher. So larger bearing clearances may be needed along with high temperature grease should be considered.

I found this out through another source.

Thanks anyway for your feedback.
 
Yes, atmospheric pressure will be higher, which helps somewhat with NPSH (available). Just as the air gets skinnier when you go up, the air gets fatter when you go to depth.

Ambient temperatures in an underground mine are dependent on a host of variables, including but not limited to: virgin rock temperature (VRT), airflows through the workings, age of the mine openings, air temperature on surface, "wetness" of the mine, cooling/refrigeration plant capacity (if used), diesel engine and electrical loads, production rates (tonnes mined per day), etc. Having said all that, I've been in plenty of mines at depths of 5000 feet (and deeper) and while it is warm, most mines are not unduly "hot". Most mining jurisdictions & mining companies maintain temperatures below about 26 Celsius (wet bulb); 80 Fahrenheit. Don't forget that people have to work in these environments.

Cheers,
CanuckMiner
 
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