10 replies to this topic

[Rahimzadeh]

Dears::
I would be so pleased if someone tell me exact definition and application of thermal safety valve?
best for all of you

[Absolute Zero]

Refer to the following link, it will explain

http://infoweb.esbe....100_GB_A_LR.pdf

[Art Montemayor]

Note the difference between this type of valve and a Thermal Expansion Valve - which is also a "safety valve", but one that relieves built-up hydraulic pressure due to temperature increases in a shut-in liquid fluid.

[Afshin445]

Mr. rahimzadeh,

Art's explanation was perfect. I just want to add that the most popular application for TSV is protection of liquid pipe between two isolation valves. In the case where the isolation valves are closed, liquid thermal expansion - due to solar radation or fire - can create a very high pressure and damage the pipe.

Edited by Art Montemayor, 18 February 2012 - 12:00 PM.

[Rahimzadeh]

Mr. Afshin:
i want to know the difference between this device and pressure safety device?
we can use pressurel safety valve instead thermal safety valve?
thank you

[fallah]

Mr Rahimzadeh,

Seems you mean relief valve....if so:

Actually thermal relief valve and pressure relief valve both are relief valves....and normally are used with an incompressible fluid...
A thermal relief valve, normally with small size, would be actuated by the static pressure at its upstream to relieve the overpressure due to thermal expansion of an incompressible fluid...
A common relief valve with liquid trim, would be actuated by the static pressure other than thermal expansion could be used as TRV provided that all requirements such as required capacity, material type, set pressure, blowdown,..., are to be met.

Fallah

Edited by fallah, 18 February 2012 - 03:57 AM.

[Rahimzadeh]

Dear Fallah:
Thank you for clear response.
It must be calibrated with thermometer or pressure gauge?

[fallah]

Mr Rahimzadeh,

Your question isn't clear to me, but actually the pressure gauge using in PSV testing (PSV set pressure and tightness) should be calibrated.

Fallah

[Rahimzadeh]

Dear fallah:
My mean is that TSV must activated in excess temperature (for example in 95 degree centigrade this valve will be openned or for example at 12 barg this valve will be opened)
Thank you

[fallah]

Mr Rahimzadeh,

As i mentioned TSV would be actuated by the static pressure at its upstream to relieve the overpressure due to thermal expansion of an incompressible fluid...means it opens at its set pressure...

Obviously, relieving temperature would be higher than normal fluid temperature and thermal expansion has been occured due to temperature rising from normal operating temperature to relieving temperature...

Fallah

[Rahimzadeh]

Mr Fallah:

your last response cleared every thing for me.
Thank you
M.R.Rahimzadeh