(b) Socket end of screw shall be flat and chamfered. The
chamfer shall extend to the minor diameter of the thread and the edge between flat and
chamfer shall be slightly rounded.
(c) Location of effective locking area "X" shall be in accordance with
MS 15981 except as noted herein.
(d) PMax. = Maximum point plus minimum
of 1 thread pitch. For ease in starting, locking element shall not be effective within
this area.
(e) Maximum major thread diameter plus .010 = Maximum ring gage diameter that locking
region of part must pass through freely or with finger
pressure.
(f) See MS51963 and MS51964 for set screw without self-locking feature.
(g) As MIL-F-18240 doesn't establish torque requirements for items
above heavy
line, only a positive indication of torque is required.
MATERIAL:
Steel, alloy (See Procurement Specification). Hardened by quenching In
oil from the hardening
temperature and tempered to a Rockwell Hardness of C 33-40
or equivalent.
LOCKING
ELEMENT:
In accordance with Specification MIL-F-18240.
DESIGN
AND USAGE
LIMITATIONS: See MS 15981.
FINISH:
Steel: Cadmium
plate Specification QQ-P-416, Type II, Class 3. Except that paragraph 4. 4. 5 is not
applicable.
EXAMPLE
OF PART
NUMBER:
MS-18063-57 = ¼-28UNF-3A x 3/4 long
cadmium plated steel cup point self-locking set screw.
