Design for Full Rating condition

[Mateus_R]

Dear All,

Could some one clarify me what the meaning of having a design (Temperature/Pressure) of a valve/pipe according to the full rating condition?

Another point that I saw in one datasheet and is confusing me: For a piping class, the customer inform: Temperature/Pressure Limits: FULL RATING #300 per ASME B16.5... from 0°C to 400°C.

From my understanding, for each value in between 0°C and 400°C I have a different value of pressure according to B16.5, so i'm a little confused about the one I need to use.

Thank you.

Best Regards.

 

[XL83NL]

I suspect, and this is also how I define our company pipe specs, is that you have to check that each such condition (0, 50, 100 .... 400 °C), the flange is the limiting factor, i.e. the weakest component. Another way of putting is that you dedign a flange rated pipe spec.

 

[LittleInch]

Mateus,

You simply take the pressure rating which is relevant to your design temperature for the particular material as per the charts in B16.5, or am I missing something here?

If your design temperature is between the steps in 16.5, then you are allowed to iterate between the steps in a linear manner.

Remember - More details = better answers
Also: If you get a response it's polite to respond to it.

 

[Mateus_R]

XL83NL, yes I also have the idea that what the spec. is asking is to confirm that the flange is not the weakest component in the whole range of Temperature.

LittleInch, i just would like to understand how to proceed facing this kind of Temperature/Pressure conditions, since in my opinion from specification this could be ambiguous. I mean, if someone gives you the Design Temperature and Pressure, why they need to specify that you need to design according to full rating condition.

Kind Regards.

 

[mk3223]

If understood correctly, as the piping spec developed with the full P-T rating based on the B16.5, the pipe, fitting, and valve on each piping class can be designed with the same P-T conditions as defined.
For applying to the specific component such as valve or fitting, the process may be presented with P-T valves per Min/Nor/Max conditions. And then, select one piping class which may cover the all the P-T ratings as specified by this process conditions.