×
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

HP steam conveying

HP steam conveying

HP steam conveying

(OP)
We are trying to determine whether it is possible to convey HP steam (500 Celcius and 60 bar) for a distance of 400 mt.
I would appreciate if any-body give a tip out of experience or calculation, related to pipe material quality,condensate amount and pressure losses?

RE: HP steam conveying

heatcycle,
          The answer is yes. We have HP steam which is conveyed further htan 400mtrs. The conditions at the other end will depend on the extent of the insulation you apply (i.e. thickness and type), the ambient conditions(heat transfer/loss), the size of the line(pressure drop). The amount of condensate again is dependant upon the physical attributes of the system.

RE: HP steam conveying

pipe material would be 1.25 Cr-1 Mo or 2.25 Cr - 1Mo ( P11 or P22) for a  500 C design temperature. Just be certain the design temperature truly represents the max temp expected for the steam.

pressure drop allowable is dependent ont he process requirements. For a power producig station, a typical HP main steam line loss at max flow is 2.5% of inlet pressure, including valves, bends, and straight portion. For other processes there is an economic tradeoff between pipig friction loss, pump power at upstream system, and desing pressure of upstream system.


Condensate piping and valves should be designed to handle the cold startup case if the steam is to go to a turbine, so one must calcualte the energy absorbed by the piping during this scenario . For an 60 bar system I would guess the drain valves and piping would be 40 mm nominal.

RE: HP steam conveying

As others have said, it is quite possible.  The pipe would be sized for a velocity likely in the range of 100 to 125 ft/sec (30 to 40 m/sec) depending on what you want to allow for pressure losses.  If you want to minimize pressure losses, go to the next larger size.  What is your intended flow rate?

For condensate losses, you'll need to do a heat transfer calculation based on your ambient conditions and what amount of insulation and type your specs call for.  If this is a fairly large flow, you typically don't lose enough heat to remove all of the superheat from the steam so calculated steam losses for operation are zero.  However, on startup you can have significant amounts of condensate as you heat the piping up to operating temperature, the duty being supplied by condensing some of the steam in the system.

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