Which steam trap is best for this application?

[ProjectEng]

I have 1250psi superheated steam as supply to a turbine. There are 400psi and 175psi saturated steam extraction lines coming off the turbine.

Which steam traps are best for the drip legs on each line? I am leaning towards sarco thermodynamic traps for all lines but the bucket trap looks appealing too.

All traps will be indoors so freezing is not an issue. I want traps I can socket-weld.

Thanks.

 

[saxon]

ProjEng., The socket weld conn. is no problem. End Conn. are an option. As for the best trap for the application, this is dependant on the condensate load and how far you are from the condensate collection header and whether or not you want to flash the condensate to supply a lower pressure stm. system.

In addition to Spirax Sarco, also check out Armstrong Int'l. in Three Rivers Mich.

Hope this helps.
saxon

 

[ProjectEng]

Condensate would go to a condensate receiver tank from where it would be fed into the condensate polishing resin beds.

Each of the 3 headers are approx 150' long. 400# header is 12". 175# header is 30". And the 1250# header is 18". Lines will be well-insulated so condensate loads should be relatively light during steady-state operation.

The manufacturers' websites seem fairly vague and even contradictory when it comes to recommending specific types of traps for certain applications.

 

[Joesteam]

Although many steam traps will work in drip service for saturated steam at 175# and 400#, I have always been partial to thermostatic traps due to the long life you get. Unlike buckets that have problems with air handling and thermodynamics that cycle all of the time and wear, thermostatics can sit closed and when they do open there is always a liquid seal. For one, look at Gestra:

http://www.gestra.com/~gestra_usa/index.html

More important than the type of trap is the design of the actual drip leg that the trap is installed on. The boot should be large enough to collect the water and the deep enough to allow seperation of liquid/gas. The trap should be off the side of the boot.

 

[rmw]

I concur with Joesteam, and add two things. With the thermostatics, there is less, but normally not a complete reduction, of the flashing of the condensate released by the trap, but the price paid is that this condensate then has to be reheated as it re-enters the condensate/feedwater cycle, putting a miniscule penalty on heat balance.

Now, I have my own question to ask; do you have provisions for start-up, and/or transient conditions when condensate loads might not be "light" or are you depending on the trap to do that for you as well?? That factor alone might well pick your trap for you.

rmw

 

[ProjectEng]

For start-up conditions where condensate loads will be relatively heavy, operators will open manual valves to quickly evacuate condensate and air.

Our driplegs are large and well-designed.