Hello Dears,

How can we determine trunnion temperature?

Thanks,

There are some methods that are used.

- Kellogg method for vessel skirt
- MSS SP 58 indication of a gradient of 2.2 deg per mm for metal parts that do not participate to flow (para 4.11)
- 1/3 hot, 2/3 cold

and maybe there are other (FEA...)

important is always that your calculation is not sensitive to this factor.

Regards,

Thank you Danb

But
- what is the Kellogg method?
- And about second method, I think it's not reasonable. Because for a trunnion with 500 mm length, temperature will be decreased to 500*2.2=1100 deg. I think it is big.

Does anyone kindly know where it is possible to buy or find the Kellogg Design Manual? It is precious reference text. I know it's not a published book....
Thank you.

Well typically it should be your ambient temperature.

- Kellogg method is a method to determine the vessel skirt expansion using the average temperature of the skirt. It depend on the skirt thickness, insulation type, skirt length, vessel temperature.
- 2.2 deg C/mm drop mean that for example for a line with 240 deg Ctemperature and 20 deg C instalation temperature, in 100 mm the trunnion will have ambient temperature and will drop no more (by the way, have you noticed that usually the trunnions are not insulated? If the temperature of the trunnion would be as for the line, personal protection insulation should be installed)

Regards,

Ya mean this Kellogg Book? http://www.amazon.com/Design-Piping-Syst...03217258&sr=8-2

No, the other one, the '88 Design manual.

Regards,