Explain definition please UW-16(f)(3)(a)(2)

[MikeG7]

Could anyone please give me some explanation of the wording of UW-16(f)(3)(a)(2)

which says:

"(2) the maximum size of the opening in the vessel is limited to the outside diameter of the attached pipe
plus 3⁄4 in. (19 mm), but not greater than one-half of the vessel inside diameter"

In what case would a fitting have an opening which is 19 mm greater than the outside diameter?
Thanks

 

[prex]

That limitation is just a maximum, and, for a 3" threaded insert, I guess the limit could be easily attained.

prex
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[MikeG7]

Thanks Prex