Question:

I have checked "impact tested" under materials tab for the components and mentioned the temperature but still I get an error even when the impact test temperature that I have set is less than the requested temperature, why?

Answer:

Let's explain the question first:

The impact test requested temperature is set in the Operating Conditions tab as follows eg. -45C :

In the nozzle standard flange and materials tab, the "Impact Tested" option has been checked and the impact test temperature mentioned to be -45C.

Now when the calculations are performed why is the impact test error reported as follows:

The answer is AutoPIPE Vessel calculates the minimum temperature without impact test for all components and would issue MDMT error if that is found to be above the requested MDMT, irrespective of whether or not the user has checked the "Impact Tested" field for that component or not.

In the above example, if the impact tested field is unchecked and the temperature removed from the nozzle standard flange and material tab, then the minimum calculated temperature which would not require impact test for the nozzle is calculated to be -20C which is more than the requested MDMT (-45C).

Hence the error is issued in the first case even when the user checks "Impact Tested".