4 replies to this topic

[Arezoo]

Hi,

I should fill up a PSV data sheet and I'm wondering anyone can answer my question:
To fill up the process information such as Density and Viscosity of process fluid, are these property in operating temperature and pressure of fluid during normal condition or in relieve temperature and set pressure of PSV?
And if I want to size a PSV which Density and Viscosity I should consider in the software? At the operating P & T or at Set pressure and relieve temperature?

Thanks

[fallah]

Do you perform the sizing by software or hand calculation? Anyway, the most important parameter among fluid properties would be Molecular Weight and compressibility factor of the fluid to be released.

Of course,normally the physical properties of the fluid at operating conditions could be submitted, but usually there is no need to specifying the density, viscosity,... in PSV data sheet.

[Arezoo]

Hi,

Thanks for your answer, but if you look at the ISA standard data sheet for Pressure relief valve, latent heate of vaporization, ratio of specific heat and operating viscosity is requested.
i use Farris software to size the PSVs and I am not sure the data I filled in the software should be at operating T and P or relief T and Set P. specially compressibility factor is very sensitive to pressure and it is a important parameter in PSV sizing.

Arezoo

[fallah]

Hi Arezoo,

At first all available operating conditions/phisical and chemical properties such as temperature,pressure,operating viscosity,MW,...along with set pressure,allowable overpressure,required relief load and back pressure should be provided for in use software.

The software using its own data base and received operating conditions and set pressure/allowable overpressure/back pressure values would calculate relieving temperature,compressibility foctor and other parameters at relieving conditions.

Thus required/selected flow area calculated by the software would be based on relieving fluid at relieving conditions.

Regards
Fallah

[ruibernardes]

Hello,
Could you inform some references for learning how to prepare and fill diferent equipment datasheets (pumps, heat exchangers, process vessel,...)?
Some good book?

thanks,
RB