Hi,
I'm confused about acceptence criteria for forming elliptical head. We prepared a control template from inside for ID 4700 diameter. Due to UG-81 we must measure knuckle radius so what is tolerance for gap with use control template? 1.25 x ID 4700 or 0.625 x ID 4700 which one?
"The inner surface of a torispherical, toriconical,
hemispherical, or ellipsoidal head shall not deviate outside
of the specified shape by more than 11/4% of D nor
inside the specified shape by more than 5/8% of D, where
D is the nominal inside diameter of the vessel shell at
point of attachment. Such deviations shall be measured
perpendicular to the specified shape and shall not be
abrupt. The knuckle radius shall not be less than that
specified."
I'm confused about acceptence criteria for forming elliptical head. We prepared a control template from inside for ID 4700 diameter. Due to UG-81 we must measure knuckle radius so what is tolerance for gap with use control template? 1.25 x ID 4700 or 0.625 x ID 4700 which one?
"The inner surface of a torispherical, toriconical,
hemispherical, or ellipsoidal head shall not deviate outside
of the specified shape by more than 11/4% of D nor
inside the specified shape by more than 5/8% of D, where
D is the nominal inside diameter of the vessel shell at
point of attachment. Such deviations shall be measured
perpendicular to the specified shape and shall not be
abrupt. The knuckle radius shall not be less than that
specified."
