4 replies to this topic

[curious_cat]

Thermodynamic Steam Trap Spec. Sheets come with a max allowable back pressure & a corresponding capacity de-rating chart. 

 

Suppose during operation this back pressure is inadvertently exceeded what is the failure mode of the trap? i.e. Will it fail close (stop relieving condensate) or fail open (blow live steam)? 

 

[breizh]

Curious_cat .

Consider the document attached .

Hope this helps.

 

Breizh

[curious_cat]

@breizh

 

Thanks for that very useful resource. But I didn't find the answer to my specific question in there. Perhaps I missed it. 

 

Do you know? i.e. If the back-pressure increases on a thermodynamic trap does it fail open or fail closed? My logic / intuition says fails close. i.e. As the back pressure rises the trap ought to find it harder to relieve against that back pressure. 

 

But I'm reading an articles that seems to say the failure mode is the exact opposite. i.e. fails open & continuously blows steam. 

[breizh]

Hi ,

Fails open ! more difficult to increase the temperature thus to close the trap .

 

http://www.tlv.com/g...-trap-l21s.html

 

Breizh

Edited by breizh, 27 September 2015 - 01:01 AM.

[Lucian Gomoescu]

Hello,

The type of stream trap mentioned above would fail open in case of a back pressure which exceeds the max. allowable limit. This is because the back pressure tends to lift the disc (see attached drawing).

Attached Thumbnails

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