×
INTELLIGENT WORK FORUMS
FOR ENGINEERING PROFESSIONALS

Log In

Come Join Us!

Are you an
Engineering professional?
Join Eng-Tips Forums!
  • Talk With Other Members
  • Be Notified Of Responses
    To Your Posts
  • Keyword Search
  • One-Click Access To Your
    Favorite Forums
  • Automated Signatures
    On Your Posts
  • Best Of All, It's Free!
  • Students Click Here

*Eng-Tips's functionality depends on members receiving e-mail. By joining you are opting in to receive e-mail.

Posting Guidelines

Promoting, selling, recruiting, coursework and thesis posting is forbidden.

Students Click Here

Jobs

Pump shop performance test

Pump shop performance test

Pump shop performance test

(OP)
I have a question on a suppliers shop test performed. The order called for a electric driven firewater pump with a 125 HP/1765 RPM motor to meet the design conditions. The supplier states that he used a 200HP/3500 RPM motor to test the pump in the shop and that it passed the performance test without giving any further information other than the pump curves. Is it possible to perform such a test with an overdesigned motor rating? how good is the pump after this testing?

RE: Pump shop performance test

If the pump was tested at twice rated speed then I can't imagine that the test is meaningful, and it's surprising that the 200 HP motor was big enough to drive the pump at twice normal speed unless the 125 HP motor is ludicrously over-sized. While it would be possible to use a VSD to lower the speed of the 200 HP motor to 1765 rpm, the motor won't deliver 125 HP at that speed (or it won't for long, ha-ha) - it will de-rated to 100 HP at 1750 rpm.

The information reported to you is at best incomplete. At worst, well... wink

RE: Pump shop performance test

A pump that takes 125 HP at 1765 RPM will require 500 HP at 3530 RPM.

Bill
--------------------
"Why not the best?"
Jimmy Carter

RE: Pump shop performance test

It isn't possible that he ran the pump to 3500rpm using a 200hp, 3500rpm motor. So, his 200hp motor was either capable of running it at 1765rpm or he ran it up to the limit of the motor (some speed below 1765rpm) and extrapolated the curve to the rated pump speed. So, ask him what he did exactly.

RE: Pump shop performance test

(OP)
Thanks ScottyUK, Waross & LionelHutz. The supplier was questioned on more details on the test performed and came back with a correction that the lab report provided by his sub was incorrect and that a 200HP motor was not used as stated before. The motor used during performance test was 500 hp, 3/60/460V, 1782 RPM. The hp was controlled by a variable frequency drive during the test. This is just confusing.

Red Flag This Post

Please let us know here why this post is inappropriate. Reasons such as off-topic, duplicates, flames, illegal, vulgar, or students posting their homework.

Red Flag Submitted

Thank you for helping keep Eng-Tips Forums free from inappropriate posts.
The Eng-Tips staff will check this out and take appropriate action.

Reply To This Thread

Posting in the Eng-Tips forums is a member-only feature.

Click Here to join Eng-Tips and talk with other members!


Resources