UG34-e

Without flange moment:

With flange moment:

UG-39(d) As an alternative to (b)(1) above, the thickness of flat heads and covers with a single opening with a diameter that does not exceed one‐half the head diameter may be increased to provide the necessary reinforcement as follows:

(1) In Eq. UG-34(c)(2)(1) or UG-34(c)(3)(3), use 2C or 0.75 in place of C, whichever is the lesser; except that, for sketches (b‐1), (b‐2), (e), (f), (g), and (i) of Figure UG-34, use 2C or 0.50, whichever is the lesser.

(2) In Eq. UG-34(c)(2)(2) or UG-34(c)(3)(5), double the quantity under the square root sign.