I have never seen that before. My guess whoever made the dwg meant the thickness is constant throughout the part. Without "constant" means the same thing.
That notation has no meaning as per any ASME Y14.5 I have. I have everything here from ANSI[ ]Y14.5M[‑]1082, to ASME[ ]Y14.5[‑]2018.
IMO - "Constant" is this individuals' way of indicating that the dimension should be a constant value, without variation (except as is allowable per the stated tolerances), throughout the entirety of the feature. This idea however, is already implied based on the basic rules of the ASME drafting standards I believe... Paraphrasing: "Yada yada... Dimensions apply to the full length, width, etc., of the feature to which they belong, unless otherwise specified... yada." I forget the specific subsection and paragraph / rule number, but that's the basic deal.
Unless it's a term defined within an in-house drafting standard, as someone above me mentioned, I'd consider ditching it.
I'm not a vegetarian because I dislike meat... I'm a vegetarian because I HATE PLANTS!!
Perhaps the intent was to do something along the lines of a controlled radius (CR), where a tolerance is given but on any one part they don't want you to jump all over the place within that tolerance. You must pick a value within the allowable range and stick with it.
Of course, that still leaves lots of ambiguity, but that would be my guess as to the original intent.
THE DRAWING(S) CONTAIN COMMON ABBREVIATIONS. IT IS THE CONTRACTORS' RESPONSIBILITY TO CORRECTLY DETERMINE THE MEANING OF THE ABBREVIATION USED (CLARIFY WITH [OWNER | CONSULTANT | ENGINEER] AS REQ'D). WHERE MULTIPLE DEFINITIONS ARE GIVEN THE MEANING OF THE ABBREVIATION SHALL BE DETERMINED FROM THE CONTEXT OF THE USAGE[. THE FOLLOWING ARE COMMON ABBREVIATIONS THAT MAY BE USED IN THE DOCUMENTS]
and then I have several hundred abbreviations that I normally don't include, but can if I have to... The last line 'strikes them out'.
Rather than think climate change and the corona virus as science, think of it as the wrath of God. Feel any better?
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