ASME section 8 Division 1 Units

[ayman zaki]

please I'm attempting to make a design of a hexane tank using asme section 8 division 1
I'm facing a units problem
I need to clarify this issue for me,
I'm checking on the internal and external pressure of the system
internal pressure is 0.5 bar and external negative pressure is -0.025 bar
also I need a clarification of what to do with the pressures, do I use them as they are or add or subtract any other pressures.
thanks in advance for your time.

[duazo2009]

please I'm attempting to make a design of a hexane tank using asme section 8 division 1
I'm facing a units problem
I need to clarify this issue for me,
I'm checking on the internal and external pressure of the system
internal pressure is 0.5 bar and external negative pressure is -0.025 bar
also I need a clarification of what to do with the pressures, do I use them as they are or add or subtract any other pressures.
thanks in advance for your time.

ayman,

You've never mention whether the given pressure are absolute or gauge. anyway if it is a design pressure, just consider it as a gauge pressure. Concerning external negative pressure, it does't mean that you're going to put a negative figure in your design. it indicates only that it is an external pressure. adding or subtracting of pressure from gauge pressure to absolute pressure is not applicable as you are in a practical application.

I hope it is clear.,,

Cheers,

duazo2009