Spec Break after Steam Trap - Why?

[sheiko]

Hi,

I have a steam heater with a steam trap at the outlet of the HP steam side.

1/ I have noticed there is a spec break after the steam trap (at outlet flange of a manual valve just downstream the steam trap) and that the ratings upstream and downstream the steam trap are significantly different.

It is not the first time i see such a thing but i can't explain why. Do you have an idea?

2/ Also, may the fluid at the steam trap inlet be "saturated condensate"? or "liquid/vapor"?

3/ And, may the fluid at the steam trap outlet be "liquid/vapor"?, "saturated steam"?

"We don't believe things because they are true, things are true because we believe them."

 

[chemjock]

Condensate return systems can run at a significantly lower pressure than the steam supply. Be careful about overpressuring the condensate system with the steam if the return system has a lower pressure rating.

The trap inlet fluid should be saturated condensate and the oulet vapor liquid.

 

[ione]

Please consider:

1. Steam line and condensate line usually experience different pressures.
2. Steam traps act as automatic valves which open to release condensate and close in presence of steam (this is virtually true as some steam could escape from the trap with variable amounts depending on trap type)
3. Released condensate is a saturated liquid which can flash again to steam. Equilibrium conditions cease as pressure changes (decreases). The amount of flash steam depends on upstream and downstream conditions

 

[rmw]

Released condensate is a saturated liquid (or possibly subcooled depending on trap type) "a portion of which" can flash again to steam.

rmw