What is the minimal pressure to use a safety relief valve
What is the minimal pressure to use a safety relief valve
(OP)
I have actually instaled a HF vaporizer operating at 24 Psig @ 150 ºF and actually we don´t use a safety relief valve, in a future the pressure to be 35 psig. The cuestion is what is the minimal pressure required to install a safety valve.





RE: What is the minimal pressure to use a safety relief valve
This is a question that should be asked of the juridiction in which the equipment is to be used. The ASME Code excludes equipment that contains less than a certain volume, but this does not necessarily exclude the equipment from the LAWS of the jurisdiction.
Regards, John.
RE: What is the minimal pressure to use a safety relief valve
The more you learn, the less you are certain of.
RE: What is the minimal pressure to use a safety relief valve
vj
RE: What is the minimal pressure to use a safety relief valve
What are you trying to say? ANY enclosed vessel or tank MAY require a relief device (vent, relief valve, rupture disk, etc). There is nothing magical about 5 bar in the USA! If a VESSEL is over 15 psig a relief valve is usually required UNLESS it cannot be overpressured from an outside source (so long as state law permits application of the ASME Code Case). Below 15 psig a vent is usually used to limit maximum pressure. So 15 psig is a bit magical - but not 5 bar.
The more you learn, the less you are certain of.
RE: What is the minimal pressure to use a safety relief valve
RE: What is the minimal pressure to use a safety relief valve
In the case of HF, its toxic effects on persons probably imply special rules, such as using a bursting disc upstream of the relief valve . A seeping relief valve is not going to be accepted by the local authority. Tremendous damage was caused in 1945 in southwestern New Jersey by a Dupont HF facility leaking HF.
This is something that cannot be designed over the internet by amateurs. I would suggest finding someone that has experience with the chemical process .
RE: What is the minimal pressure to use a safety relief valve
J. Alton Cox
President
DeLuca Test Equipment
www.delucatest,com
RE: What is the minimal pressure to use a safety relief valve
A relief device is required whenever there are credible scenarios that could cause the vessel pressure to exceed 110% of the design pressure.
A relief device is required to protect the vessel during an external fire if an external fire scenario is credible. In this case the device must be sized to prevent the pressure from increasing beyond 121% of the design pressure.
API 620 tanks(less than 15 psig design pressure):
Requirements are similar to ASME Section VIII.
API 650 tanks (less than 2.5 psig design pressure):
Relief device is required to prevent the pressure from exceeding the design pressure during normal and emergency situations.
Note: A relief device could be a relief valve, safety relief valve, conservation vent, rupture disk, etc.
RE: What is the minimal pressure to use a safety relief valve
JBO:
Does your vaporizer carry an ASME stamp and nameplate?
RE: What is the minimal pressure to use a safety relief valve
RE: What is the minimal pressure to use a safety relief valve
J. Alton Cox
President
DeLuca Test Equipment
www.delucatest,com