SS Round Head Machine Screw (INCH)
Stainless steel round head machine screws (inch series) per ANSI/ASME B18.6.3 feature a narrow cylindrical head with slotted drive and UNC imperial threads from #4 to 3/8". Available in 18-8 (304) and 316 stainless steel grades with Class 2A thread per ASME B1.1.
Specification
#
Standard
ANSI/ASME B18.6.3
Thread
Coarse (standard)
Material
Stainless Steel 304 (A2)
Grade
A2-70
Stock
In stock (304). Grade 316 available against bulk order
Head Type
Round head
Drive Type
Slotted
Thread Class
Class 2A per ASME B1.1
Finish
Plain/Passivated (stainless steel)
Dimension
#
Size (inch)
Thread Dia (min-max inch)
Pitch (TPI)
Length (inch)
Thread Length (inch)
#6
0.138-0.138
32
0.50
0.50
#8
0.164-0.164
32
0.625
0.625
#10
0.190-0.190
24
0.75
0.75
1/4"
0.250-0.250
20
1.00
1.00
5/16"
0.3125-0.3125
18
1.25
1.25
- All dimensions in inches, tolerance +/- 0.001 inch. Additional dimensions available on request.
Benefits
#
Inch-series round head machine screws address fastener space constraints in legacy equipment and imperial-designed electrical assemblies. The narrow cylindrical head fits between closely spaced components in crowded switchgear and terminal panels where wider head types cannot be installed or accessed. Slotted drive compatibility with standard flat-blade screwdrivers simplifies field maintenance without requiring specialized tooling, an advantage in repair and retrofit operations. Stainless steel construction provides corrosion resistance in environments where humidity, condensation, or chemical exposure would degrade plated carbon steel fasteners. Imperial thread sizing ensures direct replacement in existing North American equipment without re-tapping holes or modifying mounting hardware. The simple design and slotted drive keep unit costs competitive for high-volume applications where installation torque requirements remain within the capacity of hand-tightened slotted connections.
Common Applications
#
Inch-series round head machine screws serve legacy equipment and imperial-designed assemblies requiring narrow-profile fasteners.
- Legacy equipment maintenance and repair
- North American market product assembly
- Electrical panels and switchgear
- Light-duty machinery and instrumentation
- Vintage equipment restoration projects
- Lighting fixture mounting and assembly
- Low-torque fastening in confined spaces
Read Me
| Standard | ANSI/ASME B18.6.3 |
| Thread | Coarse (standard) |
| Material | Stainless Steel 304 (A2) |
| Grade | A2-70 |
| Stock | In stock (304). Grade 316 available against bulk order |
| Head Type | Round head |
| Drive Type | Slotted |
| Thread Class | Class 2A per ASME B1.1 |
| Finish | Plain/Passivated (stainless steel) |
| Size (inch) | Thread Dia (min-max inch) | Pitch (TPI) | Length (inch) | Thread Length (inch) |
|---|---|---|---|---|
| #6 | 0.138-0.138 | 32 | 0.50 | 0.50 |
| #8 | 0.164-0.164 | 32 | 0.625 | 0.625 |
| #10 | 0.190-0.190 | 24 | 0.75 | 0.75 |
| 1/4" | 0.250-0.250 | 20 | 1.00 | 1.00 |
| 5/16" | 0.3125-0.3125 | 18 | 1.25 | 1.25 |
