5/16 Allen Grub Screw (Inch)
5/16" inch-series headless set screws with cup point per ASME B18.3 and internal hex drive in alloy steel Rc 45-53. UNC threads for shaft locking in US-specification equipment at 5/16-inch diameter.
Specification
#
Standard
ASME B18.3
Material
Alloy Steel
Thread
UNC (Coarse)
Grade
12.9
Coating
Black oxide
Head Type
Headless (no head)
Drive Type
Hexagon socket (Allen key/hex wrench)
Point Type
Cup point (concave depression)
Dimension
#
Size
Thread Dia (d)
Pitch (TPI)
Length(L)
Thread Length (b)
3/16
0.1887-0.1900
24
3/16" - 1"
Full
1/4
0.2489-0.2500
20
1/4" - 1
Full
5/16
0.3113-0.3125
18
5/16" - 1 1/2"
Full
3/8
0.3737-0.3750
16
3/8" - 1 1/2"
Full
1/2
0.4985-0.5000
13
1/2" - 1 1/2"
Full
5/8
0.6232-0.6250
11
5/8" - 1 1/2"
Full
- All dimensions in inches, tolerance +/- 0.001 in. Additional dimensions available on request.
Benefits
#
Inch-series grub screws at 5/16-inch address shaft-locking requirements in US-specification machinery and legacy equipment. The cup point produces a controlled indentation on the shaft surface, providing a mechanical lock against rotational slip and axial movement. The headless design installs entirely within the threaded bore, eliminating protrusions in tight assemblies. Alloy steel hardness Rc 45-53 ensures effective indentation across common shaft materials. ASME B18.3 provides documented seating torque values for predictable installation.
Common Applications
#
Common applications for 5/16" inch-series grub screws include:
- Small instrument shaft locking (imperial)
- Electrical terminal connections
- Light-duty US-spec coupling assembly
- Precision instrument adjustment locking
- Small knob and handle attachment
Read Me
| Standard | ASME B18.3 |
| Material | Alloy Steel |
| Thread | UNC (Coarse) |
| Grade | 12.9 |
| Coating | Black oxide |
| Head Type | Headless (no head) |
| Drive Type | Hexagon socket (Allen key/hex wrench) |
| Point Type | Cup point (concave depression) |
| Size | Thread Dia (d) | Pitch (TPI) | Length(L) | Thread Length (b) |
|---|---|---|---|---|
| 3/16 | 0.1887-0.1900 | 24 | 3/16" - 1" | Full |
| 1/4 | 0.2489-0.2500 | 20 | 1/4" - 1 | Full |
| 5/16 | 0.3113-0.3125 | 18 | 5/16" - 1 1/2" | Full |
| 3/8 | 0.3737-0.3750 | 16 | 3/8" - 1 1/2" | Full |
| 1/2 | 0.4985-0.5000 | 13 | 1/2" - 1 1/2" | Full |
| 5/8 | 0.6232-0.6250 | 11 | 5/8" - 1 1/2" | Full |
