Dear all friend
I have question to asking you about the deviation of ellipsoidal head as per ASME Sec VIII div.1 UG-81 (a).
That involving the outside and inside deviation of inner surface.
The deviation can be checked by fit the temporary template into the inner surface and check the gap between template and surface.
Tolerance mention below;
Outside deviation not more than 1.1/4% of I.D.
Inside deviation not more than 5/8% of I.D.
My question is what does the outside deviation mean (dent inside or dent outside)? And what does the inside deviation mean (dent inside or dent outside)?
Thank you for all your guy reply.