×
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

Time Taken to stop a pump?

Time Taken to stop a pump?

Time Taken to stop a pump?

(OP)
I want to ask if there is an ESD interlock action to stop a pump due to any circumstances like very low level switch in a separator how much does it takes to stop the pump after the signal reached??

RE: Time Taken to stop a pump?

That depends mostly on the type and size (rotating inertia) of the pump, the pump's driver and to a somewhat lesser extent the momentum of the fluid about to through.  In general, electric drives can stop rather quickly, where internal combustion engine drivers may have slower shutdown procedures.  

What type of pump, size and driver type do you have?

Only put off until tomorrow what you are willing to die having left undone. - Pablo Picasso

RE: Time Taken to stop a pump?

(OP)

Thank you for your quick reply
The pump is centrifugal. it delivers about 300 m3/hr of contaminated water- electric motor driven.
I want to know only is that occur instantly or it takes seconds or it takes minutes?

RE: Time Taken to stop a pump?

Seconds.

Johnny Pellin

RE: Time Taken to stop a pump?

(OP)
May I ask u to give me a range??

RE: Time Taken to stop a pump?

You can kill the electric motor immediately, and depending on the pump configuration, "spin-down" will take typically 10-30 seconds before it actually comes to a stop.

RE: Time Taken to stop a pump?

300 m^3/hr is about 1321 USGPM; it "feels" like 1gibson's range of 10-30 seconds for spindown is reasonable.

Regards,

SNORGY.

RE: Time Taken to stop a pump?

depends quite a bit on the rotational speed of the pump

RE: Time Taken to stop a pump?

You need to do a transient analysis to determine the time taken. It all depends on the rotational speed of the assembly, system hydraulics, friction in the pump and moment of inertia of the pump/motor/coupling/entrained fluid.

Depending upon the system the pump could be driven by the fluid in turbine mode.

You cannot guess it.

If it is critical fit a VFD with dynamic braking. Make sure  you have safety devices for that time you lose power and the pump trips but the VFD isnt working.

SOme major installations have flywheel generators in place so that on loss of power they keep power on critical equipment to allow controlled stop. An electro mechanical UPS if you like.

"Sharing knowledge is the way to immortality"
His Holiness the Dalai Lama.

http://waterhammer.hopout.com.au/

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