Hi all, i have tried to refer API 521 5.14.4.1 for the calculating the required TRV for my case study below.
Case Study: Currently in our terminal we have an issue with the Fire water line where the line is packed with fresh water of line pressure maintained at 12 barg. Added to this, we have 3 TRV set at 14.5 barg pressure for releasing pressure added to the line by thermal expansion. Later, we have expanded our fire water line when the terminal is developed further and since then, line pressure in the fire water line suddenly increases to 15 barg even though all TRV is functioning (Note: it is happening only whenever the outside temperature is high).
To identify the cause, we may need to check the following:
1. is the current TRV size id sufficient ?
2. Additional TRV to the line?
Can i use API 521 5.14.4.1 for the above calculation? Can someone assist me how i can identify the TRV size which i use is correct and additional TRV requirement ?