huangyhg

change classifications
can someone please explain class 1 and 2 changes for drawings?
thanks!
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class i (non-interchangeable change)-
items in this category will not physically or functionally meet product specifications as a direct replacement item for all applicable applications using the previous revision. items in this category require new part numbers to be assigned.
class ii (interchangeable change)-
items in this category retain the physical and functional product specifications to act as direct replacement items for all applicable applications using the previous revision.
"art without engineering is dreaming; engineering without art is calculating."
is this an ansi definition (or some other non-private standard)?
isn't it something like mil-t-31000, i tried to find it in the asme specs a while ago and had trouble, i'd appreciated if anyone can give the ref.
one thing that occasionally gets missed on class 1 is that the changes must be both forward and backward compatible. i.e. not only must the new rev replace the old but if necessary the old rev can replace the new.
sorry, i should have noted it was non-standard, but based on a standard. i'm trying to find the mother document.
"art without engineering is dreaming; engineering without art is calculating."

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