SCREW,CAP,SOCKET HEAD-
UNDRILLED AND DRILLED,PLAIN AND SELF-LOCKING, ALLOY STEEL AND CORROSION-RESISTING STEEL,UNF-3A THREAD.
| NOMINAL SIZE DASH NO. | THREAD SIZE | D BODY DIAMETER | A HEAD DIAMETER | H HEAD HEIGHT | S HEAD SIDE HEIGHT MIN | J SOCKET SIZE | T KEY ENGAGEMENT MIN | G WALL THICKNESS MIN | R RADIUS OF FILLET UNDER HEAD | K CHAMFER OF RADIUS MAX | |||||
| MAX | MIN | MAX | MIN | MAX | MIN | MAX | MIN | MAX | MIN | ||||||
| 00 | NO. 0-80 UNF-3A | .060 | .0568 | .096 | .091 | .060 | .057 | .054 | .0510 | .0500 | .025 | .019 | .007 | .003 | .003 |
| 01 | NO. 1-72 UNF-3A | .073 | .0695 | .118 | .112 | .073 | .070 | .066 | .0635 | .0625 | .031 | .023 | |||
| 02 | NO. 2-64 UNF-3A | .086 | .0822 | .140 | .134 | .086 | .083 | .077 | .0791 | .0731 | .039 | .028 | .008 | .004 | |
| 03 | NO. 3-56 UNF-3A | .099 | .0949 | .161 | .154 | .099 | .095 | .089 | .044 | .032 | |||||
| 04 | NO. 4-48 UNF-3A | .112 | .1075 | .183 | .176 | .112 | .108 | .101 | .0952 | .0937 | .051 | .036 | .009 | .005 | .005 |
| 06 | NO. 6-40 UNF-3A | .138 | .1329 | .226 | .218 | .138 | .134 | .124 | .1111 | .1094 | .064 | .044 | .010 | .006 | |
| 08 | NO. 8-36 UNF-3A | .164 | .1585 | .270 | .262 | .164 | .159 | .148 | .1426 | .1406 | .077 | .052 | .012 | .007 | |
| 3 | NO. 10-32 UNF-3A | .190 | .1840 | .312 | .303 | .190 | .185 | .171 | .1587 | .1562 | .090 | .061 | .014 | .009 | |
| 4 | 1/4-28 UNF-3A | .250 | .2435 | .375 | .365 | .250 | .244 | .225 | .1900 | .1875 | .120 | .080 | .008 | ||
| 5 | 5/16-24UNF-3A | .3125 | .3053 | .469 | .457 | .312 | .306 | .281 | .2530 | .2500 | .151 | .100 | .017 | .012 | |
| 6 | 3/8-24UNF-3A | .375 | .3678 | .562 | .550 | .375 | .368 | .337 | .3160 | .3125 | .182 | .120 | .020 | .015 | |
| 7 | 7/16-20UNF-3A | .4375 | .4294 | .656 | .642 | .437 | .430 | .394 | .3790 | .3750 | .213 | .140 | .023 .026 | .018 .020 | .010 |
| 8 | 1/2-20UNF-3A | .500 | .4919 | .750 | .735 | .500 | .492 | .450 | .245 | .160 | |||||
| 10 | 5/8-18UNF-3A | .625 | .6163 | .937 | .921 | .625 | .616 | .562 | .5050 | .5000 | .307 | .200 | .032 | .024 | |
| 12 | 3/4-16UNF-3A | .750 | .7406 | 1.125 | 1.107 | .750 | .740 | .675 | .6310 | .6250 | .370 | .240 | .039 | .030 | |
| 14 | 7/8-14UNF-3A | .875 | .8647 | 1.312 | 1.293 | .875 | .864 | .787 | .7570 | .7500 | .432 | .280 | .044 .050 | .034 .040 | .015 |
| 16 | 1 -12UNF-3A | 1.000 | .9886 | 1.500 | 1.479 | 1.000 | .988 | .900 | .495 | .320 | |||||
NOTES:
(a) THESE THREAD SIZES ARE PREFERPED PER SPEC MIL-S-7742.
(b) “M” MIN (5 THREAD PITCHES)-REGION OF MINIMUM ENGAGEMENT WITH FULL FEMALE THREAD REQUIRED TO MEET SPEC MIL-F-18240
REQUIREMENTS.
LOCKING ELEMENT WITHIN “M” REGION MUST DEVELOP REQUIRED TORQUE WHEN TESTED IN ACCORDANCE WITH SPEC MIL-F-18240.
LENGTH OR DIAMETER OF LOCKING ELEMENT MAY BE MORE OR LESS THEN “M” PROVIDING ALL OTHERS REQUIREMENTS ARE MET.
(c) “N” – ONE (1) COMPLETE THREAD PLUS UNTHREADED PORTION OF END.FOR EASE IN STARTING.LOCKING ELEMENT SHALL NOT BE
EFFECTIVE WITHIN THIS AREA.
(d) SCREWS WITCH HAVE A LENGTH LESS THEN THE MINIMUM BASIC THREAD LENGTH,SHALL BE THREADED AS CLOSE TO HEAD AS
PRACTICABLE.
(e) DRILLED HOLE DATA IN ACCORDANCE WITH PROCUREMENT SPEC FF-S-86.
SCREW SIZES NO. 4 AND NO. 6 SHALL HAVE TWO (2) DRILLED HOLES SPACED 180°.
SCREW SIZES NO. 8 THRU 1 INCH SHALL HAVE SIX (6) DRILLED HOLES SPACED 60°.
(DRILLED HOLES NOT APPLICABLE TO SCREW SIZES BELOW NO. 4).
THREADS: THREADS IN ACCORDANCE WITH SPEC MIL-S-7742.
MATERIAL : ALLOY STEEL IN ACCORDANCE WITH PROCUREMENT SPEC FF-S-86.
CORROSION-RESISTING STEEL IN ACCORDANCE WITHPROCUREMENT SPEC FF-S-86.
FINISH : ALLOT STEEL-CADMIUM PLATE IN ACCORDANCEWITH SPEC QQ-P-416,TYPE II,CLASS 3.
– BLACK OXIDE IN ACCORDANCE WITH SPEC MIL-C-13924,CLASS 1.
CORROSION-RESISTING STEEL – CADMIUM PLATE IN ACCORDANCE WITH SPEC QQ-P-416,TYPE I,CLASS 3.
-PASSIVATE IN ACCORDANCE WITH PROCUREMENT SPEC FF-S-86.
CODE : METERIAL CODE,”-“= ALLOY STEEL.
“C” = CORROSION-RESISTING STEEL.
FIRST CODE DASH NUNBER DESIGNATES SCREW THREAD SIZE AS TABULATED.
TYPE CODE,”-” = UNDRILLED HEAD.
“H”= DRILLED HEAD.
“LE” = SELF -LOCKING MALE THREADED FASTENER.
(OPTIONAL TYPE LOCKING ELEMENT IN ACCORDANCE WITH NAS1283).
“LL” = SELF LOCKING MALE THREADED FASTENER.
(LONGITUDINAL STRIP LOCKING ELEMENT IN ACCORDANCE WITH NAS1283,TYPE L).
“LN” = SELF LOCKING MALE THREADED FASTENER.
(PELLET LOCKING ELEMENT IN ACCORDANCE WITH NAS1283,TYPE N).
SECOND DASH NUMBER DESIGNATES NOMINAL LENGTH IN SIXTEENTHS OF AN INCH AS TABULATED.
TABULATED CODING INDICATES PREFERRED LENGTHS.
ADDITIONAL LENGHTS AVAILABLE ON SPECIAL PRDER ,MINIMUM RUN BASIS.
FOR SUCH LENGTHS ADDITIONAL CODING MAY BE ASSIGNED TO LENGTHS IN 1/4 INCH INCREMENTS UP TO 3-1/2 INCHES,
AND IN 1/2 INCH INCREMENTS FROM 3-1/2 INCHES UP TO AND INCLUDING 6 INCHES.
FINISH CODE,ALLOY STEEL “P” = CADMIUM PLATE.
NO SUFFIX CODE FOR BLACK OXIDE.
CORROSION -RESISTING STEEL ,”P” = CADMIUM PLATE.
NO SUFFIX CODE FOR PASSIVATE.