Field Testing of Pumps and Blowers onsite

[extremechanical]

Dear Learned professionals,

Excuse me for my ignorance and help me!!

Please let me know a simple and reliable ( I dont intend to repeat Factory/ PTC tests) procedure how to test a centrifugal pump for capacity and Head at site ( as installed) .
Also please let me know how to test Lobe and Centrifugal Blower on site as installed.

Just to tell you, I have already FAT ( factory acceptance test reports) for all pumps and Blowers.

IN this regard, if you have a template/ format made for recording the reading that will be of great help...!

By the way we dont have flow trasmitters for all pumps. Is it ok to use power formula to arrive at capacity, taking efficiency into consideration?

Thanks a lot.

 

[BigInch]

You could estimate flow based on power, or power based on flow. Your problem will be how to get pump and motor efficiencies without flow data. Is that how you really want to do field performance testing. Speaking of that, do you just want to estimate performance, or is it an actual proof of performance for contractual reasons. If its proof you're looking for, I doubt an estimate will suffice. Why not at least try to get hold of a portable ultrasonic flowmeter and try to do this with some degree of certainty.

"The top of the organisation doesn't listen sufficiently to what the bottom is saying." Tony Hayward X-CEO BP
"Being GREEN isn't easy." Kermit

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

http://virtualpipeline.spaces.live.com

 

[extremechanical]

Biginch,

Thanks a lot for the useful reply.. thanks ..takecare

 

[stanier]

Suggest you rnt a clamp on ultrasonic meter and obtain yourflow versus pressure data.

“In physical science the first essential step in the direction of learning any subject is to find principles of numerical reckoning and practicable methods for measuring some quality connected with it. I often say that when you can measure what you are speaking about, and express it in numbers, you know something about it; but when you cannot measure it, when you cannot express it in numbers, your knowledge is of a meagre and unsatisfactory kind; it may be the beginning of knowledge, but you have scarcely in your thoughts advanced to the state of Science, whatever the matter may be."

Lord Kelvin [PLA, 1883-05-03]

 

[dabluffrat]

Portable ultrasonic flow meters are useful, but you have to know how to configure the settings to really trust the readings you'll get.

You should be able to calculate the pump head based on suction and disch pressures. If it's a low head pump don't forget to add back in velocity head and gauge elevation. And you should be able to estimate the power based on motor amps or KW readings (input KW / motor effy / 0.746 x Sp Gr = bhp). Some are going to argue a nominal motor efficiency isn't accurate and you need to know where you're running on the motor's power curve, but for an approximation it's close enough.

Both of these should give a pretty indication of the expected flow rate. Then compare that flow to the output on the ultrasonic flow meter.

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

 

[ccfowler]

extremechanical,

You will want to be sure of the exact shaft speed of the pump during your performance tests. Small variations of shaft speed can easily result in misleading data or interpretation of actual performance.

Valuable advice from a professor many years ago: First, design for graceful failure. Everything we build will eventually fail, so we must strive to avoid injuries or secondary damage when that failure occurs. Only then can practicality and economics be properly considered.

 

[extremechanical]

Stanier, dabluffrat and ccfowler... thanks a lot