×
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

Automatic Start-up of steam turbine driven lube oil pump
2

Automatic Start-up of steam turbine driven lube oil pump

Automatic Start-up of steam turbine driven lube oil pump

(OP)
Hi All,
We have these large process gas compressors on the ongoing construction of our Ethylene Cracker Plant. One of our current issue is about the lube oil pump operation. The main lube oil pump is a steam turbine driven and an auxiliary pump that is motor driven. However, one question arise during our Hazop, that the event of maintenance of the steam turbine driven pump, the motor driven pump will be online. Then after maintenance, the steam turbine driven pump will be the standby pump. However, to have the flexibility of operation, we want these steam turbine driven pump to be on auto-start-up which would modify the lube oil accumulator sizing. The normal start-up of a motor is 4 seconds while on the turbine that we bought is 17 seconds and will have an impact on the accumulator sizing. What is your current design on your plant?

RE: Automatic Start-up of steam turbine driven lube oil pump

To avoid having to add additional control and bigger accumulator, just  switch back to steam turbine driven pump as main after maintenance. The reason to use steam turbine driven as main is because of extra steam availability and its reliability.

RE: Automatic Start-up of steam turbine driven lube oil pump

(OP)
Thanks Pumpsonly, how about the flexibility of operation?

RE: Automatic Start-up of steam turbine driven lube oil pump

We would not normally require auto-starts on both the motor and the turbine drivers. We would run the turbine and auto-start the motor.  I see very little value in setting it up for auto-start of the turbine.  And, since it would complicate the design of the accumulators, I would not bother.

Johnny Pellin

RE: Automatic Start-up of steam turbine driven lube oil pump

(OP)
Hi JJPelin, what we are considering on the auto start-up of the turbine is an operator error after the maintenance of the steam turbine driven lube oil pump. The possibility of switching from the motor to the turbine after maintenance will be a possibility and once happened a 1.5 million dollar minimum shutdown cost because of the compressor lube oil system will cost the plant...Hoping for your comments.thank you very much

RE: Automatic Start-up of steam turbine driven lube oil pump

I would still not add the auto-start on the turbine.  By complicating the design of the accumulators, you could end up causing another problem.  If you have run status for the motor driver, set up an alarm that the board operator has to acknowledge once per shift.  The board operator will make sure that they switch back to the main pump.  

If you try to make the system idiot proof, someone will just come along and invent a better idiot.

Johnny Pellin

RE: Automatic Start-up of steam turbine driven lube oil pump

(OP)
Hi JJPelin, thanks again for your suggestion. For the accumulators, what would only the change is between a 4 sec start of the motor and the 17 seconds start of the turbine. It will be a matter of additional size of the accumalator. Would there still i'm missing on the lube oil design once we adopt the auto start-up of the steam turbine?

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