Dear All,
for liquid thermal expansion of liquid full piping which can be blocked in with more than 95% and where presence of noncondensable vapors is not envisaged to preclude liquid expansion as explained in section 4.4.12 in API 521 7th edition. Section 4.4.12.4.2 is also discussing the role of the trapped volume in determining the requirement for the TERV, appreciate your views on the following:
- typically any liquid system which can be blocked in with liquid full section at 95% and above required TERV.
- what is the volume criteria dictating the thermal expansion, I think this can't be generalized, some guidelines calling for 500 L of LPG and volatile/toxic liquids where the leak is quite of a concern.
- Do you agree that the lower the initial operating temperature in comparison with the maximum expected solar Black body temperature, the greater is the concern of thermal expansion associated pressure rise?
- do you agree that for water full system, the concern is higher than other high API crude oil since the cubical thermal expansion is relatively higher with associated higher density contributing to faster pressurization rate for the same incremental increase in the temperature.
I am explicitly addressing liquid thermal expansion and NOT thermal vapor relief considering that the liquid will not reach its boiling point at the relieving pressure nor have a vapor pressure exceeding the design pressure.
regards,
for liquid thermal expansion of liquid full piping which can be blocked in with more than 95% and where presence of noncondensable vapors is not envisaged to preclude liquid expansion as explained in section 4.4.12 in API 521 7th edition. Section 4.4.12.4.2 is also discussing the role of the trapped volume in determining the requirement for the TERV, appreciate your views on the following:
- typically any liquid system which can be blocked in with liquid full section at 95% and above required TERV.
- what is the volume criteria dictating the thermal expansion, I think this can't be generalized, some guidelines calling for 500 L of LPG and volatile/toxic liquids where the leak is quite of a concern.
- Do you agree that the lower the initial operating temperature in comparison with the maximum expected solar Black body temperature, the greater is the concern of thermal expansion associated pressure rise?
- do you agree that for water full system, the concern is higher than other high API crude oil since the cubical thermal expansion is relatively higher with associated higher density contributing to faster pressurization rate for the same incremental increase in the temperature.
I am explicitly addressing liquid thermal expansion and NOT thermal vapor relief considering that the liquid will not reach its boiling point at the relieving pressure nor have a vapor pressure exceeding the design pressure.
regards,