target plate 1

[wickdana]

When we start-up the new Boiler (Press. 40 Kg/cm2), we blow off the steam product and we install target plate at the end of main steam pipe. The pitting of the target plate during the blowing off give an indication of solid particles in boiler and pipe. The boiler steam will be used for power turbine.
Are there standard for acceptance criteria of solid particles in the boiler which identify at the target plate?
What material of the target plate on standards (if any)?
Thank you for your help.

 

[MJCronin]

wick,

This is a good question..... I investigated this specific issue a couple of years ago for HRSG steam-blow and startup.

The short answer to the question is no..... there are no objective criteria for target plate cleanliness. Most typically the steam turbine rep is on-site and reviews the plate and says either "OK" or not.

I have heard of much discussion on this topic. GE has written a couple of technical guidlines on this subject and proceedures for steam-blow. The GER series of guidlines address this....

The target plate material is polished mild steel. I cannot recall the typical polish.

Make sure that you provide enough anchors and guides in any temporary steam blow piping. There will be considerable reaction forces.

Many firms offer chemical flushing and steam-blow services

See

http://www.steamblow.com

and

http://www.hydrochem-csu.com

MJC