×
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

Pumps replacement study
3

Pumps replacement study

Pumps replacement study

(OP)
Hello my friends, I need some guidance of how I should start an evaluation for a pumps replacemnt and installation of an used one.

The two pumps( 5 hp, 5 gpm @ 172 rpm electric motors) are for E.Glycol injection  service in order to avoid hydrates formation at a gas processing facilities( 900 psi @ -10ºF).
The main reason of this replacemnt is the old condition. They are been operating since 1984, and has many overhauls. Now both of they, are experiencing a bad performance, and the recommendations are the replacemnt of the pumps.

We have two pumps at the warehouse that had been used for the same service in another plant. The electric motors are of the same power (5 HP @ 350 rpm)

I would like to know if a I can install this pumps at the plant, and what points do I have to consider for start the evaluation.

I will appreciate your comments

Regards

RE: Pumps replacement study

Firstly, you need to establish what the design duty / requirements of the existing pump / system is and secondly, what is the rated output of the warehoused pump -if the performance is the same then it is likely you might be able to use it.
You also need to establish what the mechanical condition of this pump is, is it in any better shape than the one already installed.
    

Naresuan University
Phitsanulok
Thailand

RE: Pumps replacement study

your conditions of 5 gpm at 900 psig call for a 3HP motor, that checks.  Now the new pumps must first be able to withstand the presure and that they pump 5 gpm at the speed they are rated at.  Typically on these small PD pumps, you can get higher discharge pressures by putting in smaller plungers (there is a rodload issue normally) sometimes the fluid end with the valves can be chaned out for higher pressures if required.

For flowrate, either slow the units down by resheaving (I assume that they are)or somethimes there is a gearbox that has to be changed.  

Overall most pumps have a table showing all the variations of plunger size versus flow rate with maximum allowable pressures for each plunger/head.

The last thing to check is NPSH, most PD pumps require very little, but given the choice of multiple diameters and speed, I'd chose the lower speed to get the lowest NPSH and best chance of longivity.

Have an expert give it a once over too.

RE: Pumps replacement study

(OP)
Thanks to all !!, we will keep in touch

RE: Pumps replacement study







 Monagas, try this software for free.

 

 "ProMot, a decision support tool, is being developed within the framework of a project cofinanced by SAVE, aiming to aid end-users to explore the possibility of energy savings, in motor systems of an industrial or tertiary installation: electric motors, pumps, compressed air system and chillers.      The tool helps in auditing an installation and performing simple meaningful calculations of purchasing, replacing existing or retrofitting electric motor systems. These technical and economic calculations are based on equipment data retrieved from widely accepted and regularly updated European databases and methodologies."



 Download at this link,

 http://promot.cres.gr/promot_plone/downloads/tools





regards,

bil








RE: Pumps replacement study

(OP)
Thank You Mr. Bill

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