Item # DHSHCS03125XXX, Drilled Hexagon Socket Head Cap Screw, 0.3125" Nominal Dia. On Sales Systems Ltd.

Nominal Size. Where specifying nominal size in decimals, zeros preceding decimal and in the fourth decimal place shall be omitted.
Screws. Drilled hexagon socket head cap screws shall conform to the respective dimensions and requirements set forth.
Number of Holes. Screws shall have 2, 4, or 6 holes drilled in the head as designated by the purchaser. For sizes 6 (0.138 in.) and smaller, the use of only 2 holes is recommended.
Holes. Hole size and location from the top of the head shall conform to the specifications given in this table. For sizes 8 (0.164 in.) and larger, the drilled hole shall lie within the flats of the hexagon socket and not break through the socket corners. Positioning of holes on opposite sides of the socket shall be such that the hole alignment check plug will pass completely through the head on all screw sizes.
For commercial quality screws, the edge of the holes on the outside of the head may be chamfered or broken. The edge of the holes within the socket may contain burrs to the extent that the socket will accept a key having the standard minimum width across the flats and the holes must allow the Type I drill check plug to pass from the outside of the head into the socket.
For aircraft quality screws, the edge of the holes on the outside of the head shall be chamfered and there shall be no burr chips or slivers that might become dislodged during usage. The socket shall accept a key having the standard.

Unit of Measure

Manufacturer | Specifications | Codes and Standards

N/A Industrial Fasteners Institute

Product	N/A Socket Screws
Unit of Measure	N/A English
Nominal Size or Basic Screw Dia.	N/A 5/16 in
Nominal Size or Basic Screw Dia. (Decimal)	N/A 0.3125 in
Drilled Hole Dia. Number (U)	N/A 56
Basic Drilled Hole Dia. (U)	N/A 0.0465 in
Max. Head to Center of Hole (V)	N/A 0.104 in
Min. Head to Center of Hole (V)	N/A 0.084 in
Basic Type I Drill Check Plug Dia.	N/A 0.035 in
Basic Type II Drill Check Plug Dia.	N/A 0.044 in
Hole Alignment Check Plug Dia.	N/A 0.030 in

N/A ASME B18.3 2002

Manufacturer