Does anyone know what spec defines a Temperature range of 68°-72° for dimensional measurement? Every spec Ive looked at thus far defines the temp as 68° period. If you deviate from that temp you must compensate for thermal effects. The reason Im asking is because we are manufacturing a magnesium housing that has a 23.501" +/-.001 dia. If we check it in the shop (71°) it checks 23.501, check it in the lab (68°) it checks 23.499 which obviously is undersize..
68° is considered room temperature, the idea temperature for checking parts. A long, long time ago in a far away galaxy 72° used to be considered room temperature. I'm guessing 1973 version. Somewhere along the line someone came up with the 68°-72° range. When actually it is just 68° If we are talking about ASME of course. I believe it was the 82 version that first started 68°
Ok
2013_junkie I can probably email you the standard
DAN_M is correct with the 50% RH but the +/- thing is incorrect. It's 68° in that standard too. If it's anything other than that temperature then there are formulas you use to calculate from your results. If you want to get into it that deep I will gladly send you a copy. and I was wrong this actually relates to the 73 version. So the 72° thing not sure of where that came from.
Here is just an example. This $hit goes on and on.
I have all these specs so no need to send me anything. I've studied these specs a lot over the last year for Boeing and NapCap audits and never could find a range. I just got in a heated argument this morning between Engineering/Mill about what temp the housing can be inspected at. They were swearing up and down the wall that it was allowed to be measured anywhere in that range. In the end they lost and I won Thanks for your help guys.
