Will new TD trap passes steam?

[murphymok]

Hi,

I am wondering will a new TD steam trap passes any steam during operation? I heard that a perfect condition TD trap will still passes some steam.

Thanks.

 

[TBP]

The two main problems with thermodyamic steam traps are common to all components in many (if not most) steam systems:

1/ They are routinely GROSSLY oversized.

2/ They are routinely installed on applications where they should not be.

 

[MintJulep]

A properly functioning TD steam trap should not continually pass steam.

It will of course allow some through before it closes.

 

[Joesteam]

It is very interesting the design of TD traps. Some are made with intentional sub-cooling that will always have a liquid seal on the seat so it will pass no steam. Others are 'hotter' and may loose some. The discs are etched to try to allow air through on start-up, which they are not very good at, but this may allow a bit of steam, too.

At low differential pressures the trap will fail open and pass live steam. I usually do not recommend these traps for systems under 50 psig.

 

[friartuck]

The disc is forced against the seat by high velocity steam...so by design, steam passes.

A space above the disc keeps it seated until the pressure drops.

Best speaking to spirax sarco or one of the other big ST manufacturers to ascertain which trap is suited to your application.

Incidently, what is that?

Friar Tuck of Sherwood

 

[quark]

Apart from what TBP suggested, a new TD trap passes if,

1. The ambience is very cold (insulated cap TD traps are developed to tackle this issue)
2. If there is any debris between the disc and the seat (fine welding flux etc.)


Regards,