×
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

Bareshaft horsepower

Bareshaft horsepower

Bareshaft horsepower

(OP)
Can someone please explain the term 'Bareshaft Horsepower' to me. Thanks

RE: Bareshaft horsepower

The terminology I know is BHP, Brake Horsepower. It is the Horsepower made available for driving machinery other than itself, as it could be measured by a dynamometer.

RE: Bareshaft horsepower

Also I have seen the term "shaft horsepower" used to describe the same thing as brake horsepower mentioned by aolalde.

I have never heared bareshaft horsepower.  Sounds like two possibilities:
1 - They meant brake or shaft horsepower.
2 - Maybe they were trying to refer to electric power which must be supplied to keep a motor running at no load (bare shaft = no load?) ?  In that case it is only a small amount a few percent of full load necessary to supply internal motor losses.

I would ask them for clarification.

=====================================
Eng-tips forums: The best place on the web for engineering discussions.

RE: Bareshaft horsepower

(OP)
This is a reply I got from Artesi in the pump engineering forum

Bare-shaft horse power is, in the case of a pump unit - the power input to the pump shaft (which already includes the pump losses and ineficiencies),it does not include any losses for the coupling or the drive unit.

To put it another way: if the pump at the point of best efficieny requires 100kW and the loss through the coupling is 0.5kW and the inefficiencies of the electric motor driver are 3.5kW,then the energy input to operate the pump at BEP would be 104kW, calculated from voltage, amps,power factor, efficiency etc.
This becomes the input power to the pump unit as compared to the input power at the pump shaft, ie., 100/104 Kw .

If it was a engine driven unit, you would need to measure the fuel input and convert that to total energy input - this is not so easy to do but can be calculated by the engine manufacturer.   
Naresuan University
Phitsanulok
Thailand
 

RE: Bareshaft horsepower

That is a new one on me. That iswhat Ithought was BHP, but sounds as though they break it down a little further.
So would it be abbreviated as BS-HP?

Got my new info for the day, thanks.
I'm taking the rest of the day off now.

RE: Bareshaft horsepower

Sparkyman.

The second part of your post contradicts the first paragraph.

“Bare-shaft horse power is, in the case of a pump unit - the power input to the pump shaft (which already includes the pump losses and inefficiencies),it does not include any losses for the coupling or the drive unit.”  -- THIS DEFINES EXACTLY BREAKE HORSEPOWER  BHP.

I wonder, how did you messed with the motor if “it does not include any losses for the coupling or the driven unit”?

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