TABLE 9.4 PREFERRED SCREW LENGTHS AND HEADS FOR MACHINE SCREWS | ||||||||
---|---|---|---|---|---|---|---|---|
NOMINAL SIZE OF SCREW - NUMBERS AND FRACTIONAL SIZES | ||||||||
Machine | 2 | 4 | 6 | 8 | 10 | 1/4 | 5/16 | 3/8 |
Screw | Threads | Per Inch | ||||||
Lengths | 56 | 40 | 32 | 32 | 24 | 20 | 18 | 16 |
Inches | 32 | |||||||
1/8 | FRPS | FRPS | RPS | RPS | ||||
3/16 | FRP | FRP | ||||||
1/4 | FRPS | FRPS | FRPS | FRPS | FRPS | |||
5/16 | FRP | FRP | ||||||
3/8 | FRPS | FRPS | FRPS | FRSP | FRPS | HFRPS | HFRPS | |
1/2 | FRPS | FRPS | FRPS | FRPS | FRPS | HFRPS | HFRPS | |
3/4 | FRPS | FRPS | FRPS | FRPS | FRPS | HFRPS | HFRPS | FRHS |
1 | FRPS | FRPS | FRPS | FRPS | FRPS | HFRPS | HFRPS | FRHS |
1 1/4 | FRPS | FRPS | FRPS | FRPS | HFRPS | FRHS | ||
1 1/2 | FRPS | FRPS | FRPS | HFRPS | HFRPS | FRHS | ||
1 3/4 | FRPS | FRPS | FRPS | HFRPS | FHS | |||
2 | FRPS | FRPS | FRPS | HFRPS | HFRPS | FRHS | ||
2 1/2 | HFRPS | FR | FRHS | |||||
3 | HFRPS | FR | FHS | |||||
3 1/2 | H | |||||||
4 | H |
H - HEX HEAD
F - FLAT HEAD 82 DEGREES COUNTERSINK
R - ROUND HEAD
P - FILLISTER HEAD
S - SOC HEAD