Description
Smooth Body Rivet Nut Sizes, Grip Ranges & Specifications
Compare small and large flange smooth body rivet nuts in standard inch and metric thread sizes. The charts below list part numbers, recommended mounting hole sizes, grip ranges and key dimensions for product selection and RFQ submission.
Small Flange Smooth Body Rivet Nuts
Small flange smooth body rivet nuts are ideal when a lower-profile head is preferred while still providing secure internal threads in thin materials.
THREAD SIZE(UNC) |
PART NO. |
HOLE SIZE+0.004 / -0.0 |
Body Dia. /D+0.0 / -0.004 |
Length / L±0.015 |
Head Dia. / A±0.012 |
Head Height / H+0.006 / -0.002 |
GRIP RANGE |
| UNC 4-40 | SAI3 | 0.192 | 0.188 | 0.355 | 0.228 | 0.02 | 0.02-0.08 |
| UNC 6-32 | SAI4-632 / SAI4-632K | 0.253 | 0.249 | 0.409 | 0.289 | 0.02 | 0.02-0.10 |
| UNC 8-32 | SAI4-832 / SAI4-832K | 0.253 | 0.249 | 0.409 | 0.289 | 0.02 | 0.02-0.10 |
| UNC 10-24 | SAI5-1024 / SAI5-1024K | 0.284 | 0.28 | 0.464 | 0.32 | 0.02 | 0.02-0.10 |
| UNF 10-32 | SAI5-1032 / SAI5-1032K | 0.284 | 0.28 | 0.464 | 0.32 | 0.02 | 0.02-0.10 |
| UNC 1/4-20 | SAI6 / SAI6-K | 0.378 | 0.374 | 0.575 | 0.414 | 0.02 | 0.04-0.15 |
| UNC 5/16-18 | SAI8 / SAI8-K | 0.42 | 0.414 | 0.63 | 0.456 | 0.02 | 0.04-0.15 |
| UNC 3/8-16 | SAI10 / SAI10-K | 0.504 | 0.5 | 0.708 | 0.54 | 0.02 | 0.04-0.16 |
THREAD SIZE(Metric) |
PART NO. |
HOLE SIZE+0.1/-0.0 |
Body Dia. /D +0.1/-0.0 |
Length / L±0.4 |
Head Di.a / A±0.3 |
Head Height / H+0.15 / -0.05 |
GRIP RANGE |
| M3x0.5 | SEM3 | 5.1 | 5 | 9 | 6 | 0.5 | 0.5-2.0 |
| M4x0.7 | SEM4 / SEM4-K | 6.1 | 6 | 10 | 7 | 0.5 | 0.5-2.5 |
| M5x0.8 | SEM5 / SEM5-K | 7.1 | 7 | 12 | 8 | 0.5 | 0.5-2.5 |
| M6x1.0 | SEM6 / SEM6-K | 9.1 | 9 | 15 | 10 | 0.5 | 1.0-4.0 |
| M8x1.25 | SEM8 / SEM8-K | 11.1 | 11 | 16 | 12 | 0.5 | 1.0-4.0 |
| M10x1.5 | SEM10 / SEM10-K | 13.1 | 13 | 18.6 | 14 | 0.5 | 1.0-4.0 |
| M3x0.5 | SAM3 | 4.9 | 4.8 | 9 | 5.8 | 0.5 | 0.5-2.0 |
| M4x0.7 | SAM4 / SAM4-K | 6.4 | 6.3 | 10 | 7.3 | 0.5 | 0.5-2.5 |
| M5x0.8 | SAM5 / SAM5-K | 7.2 | 7.1 | 12 | 8.1 | 0.5 | 0.5-2.5 |
| M6x1.0 | SAM6 / SAM6-K | 9.6 | 9.5 | 15 | 10.5 | 0.5 | 1.0-4.0 |
| M8x1.25 | SAM8 / SAM8-K | 10.6 | 10.5 | 16 | 11.5 | 0.5 | 1.0-4.0 |
| M10x1.5 | SAM10 / SAM10-K | 12.8 | 12.7 | 18.6 | 13.7 | 0.5 | 1.0-4.0 |
Large Flange Smooth Body Rivet Nuts
Large flange smooth body rivet nuts provide a wider bearing surface for better load distribution, especially in softer materials or oversized holes.
THREAD SIZE(UNC) |
PART NO. |
HOLE SIZE+0.004 / -0.0 |
Body Dia /D+0.0 / -0.004 |
Length / L±0.015 |
Head Dia / A±0.012 |
Head Height / H+0.006 / -0.002 |
GRIP RANGE |
| UNC 4-40 | BAI3 | 0.20 | 0.20 | 0.39 | 0.32 | 0.03 | 0.02-0.08 |
| UNC 8-32 | BAI4 / BAI4-K | 0.24 | 0.24 | 0.41 | 0.35 | 0.03 | 0.02-0.10 |
| UNC 10-24 | BAI5 / BAI5-K | 0.28 | 0.28 | 0.45 | 0.39 | 0.04 | 0.02-0.10 |
| UNC 1/4-20 | BAI6 / BAI6-K | 0.36 | 0.35 | 0.57 | 0.51 | 0.06 | 0.04-0.15 |
| UNC 5/16-18 | BAI8 / BAI8-K | 0.44 | 0.43 | 0.65 | 0.57 | 0.06 | 0.04-0.16 |
| UNC 3/8-16 | BAI10 / BAI10-K | 0.52 | 0.51 | 0.79 | 0.63 | 0.06 | 0.04-0.16 |
THREAD SIZE(Metric) |
PART NO. |
HOLE SIZE+0.1/-0.0 |
Body Dia /D +0.1/-0.0 |
Length / L±0.4 |
Head Dia / A±0.3 |
Head Height / H+0.15 / -0.05 |
GRIP RANGE |
| M3x0.5 | BEM3 | 5.1 | 5.0 | 9.0 | 8 | 0.8 | 0.5-2.0 |
| M4x0.7 | BEM4 / BEM4-K | 6.1 | 6.0 | 10.5 | 9 | 0.8 | 0.5-2.5 |
| M5x0.8 | BEM5 / BEM5-K | 7.1 | 7.0 | 11.5 | 10 | 1 | 0.5-2.5 |
| M6x1.0 | BEM6 / BEM6-K | 9.1 | 9.0 | 14.5 | 13 | 1.5 | 1.0-3.5 |
| M8x1.25 | BEM8 / BEM8-K | 11.1 | 11.0 | 16.5 | 14.5 | 1.5 | 1.0-4.0 |
| M10x1.5 | BEM10 / BEM10-K | 13.1 | 13.0 | 20 | 16 | 1.6 | 1.0-4.0 |
What Is a Smooth Body Rivet Nut?
A smooth body rivet nut is a round blind threaded insert used to create a strong, reusable internal thread in thin sheet metal, tubing, panels and other materials that cannot be tapped effectively.
The rivet nut is inserted into a properly sized round mounting hole and installed from one side using a compatible rivet nut tool. During installation, the body collapses behind the material and clamps the fastener securely to the panel.
Smooth body rivet nuts—also searched as round body rivet nuts, blind rivet nuts, threaded nut inserts, rivet nut inserts and nutserts—are commonly selected for general industrial assembly because they fit standard round holes and require no welding or backside access.
Compared with knurled or hex body rivet nuts, smooth body designs offer straightforward installation and economical performance for applications with moderate torque requirements.
Available Thread Sizes
Smooth body rivet nuts are available in standard UNC, UNF and metric thread sizes. Small and large flange availability varies by thread size, material and part number.
Inch Thread Sizes
- #4-40 UNC Smooth Body Rivet Nut
- #6-32 UNC Smooth Body Rivet Nut
- #8-32 UNC Smooth Body Rivet Nut
- #10-24 UNC Smooth Body Rivet Nut
- #10-32 UNF Smooth Body Rivet Nut
- 1/4-20 UNC Smooth Body Rivet Nut
- 5/16-18 UNC Smooth Body Rivet Nut
- 3/8-16 UNC Smooth Body Rivet Nut
Metric Thread Sizes
- M3 × 0.5 Smooth Body Rivet Nut
- M4 × 0.7 Smooth Body Rivet Nut
- M5 × 0.8 Smooth Body Rivet Nut
- M6 × 1.0 Smooth Body Rivet Nut
- M8 × 1.25 Smooth Body Rivet Nut
- M10 × 1.5 Smooth Body Rivet Nut
Mounting hole size, grip range, body diameter, overall length and flange dimensions vary by thread size and part number. Refer to the specification charts above for exact measurements.
Small Flange vs. Large Flange Rivet Nuts
Small flange rivet nuts have a lower-profile head that minimizes projection above the panel. They are suitable when appearance, clearance or a nearly flush mating surface is important.
Large flange rivet nuts provide a larger bearing surface on the front of the panel. The wider flange helps distribute load and may provide additional support in thin or softer materials.
The correct flange style depends on panel material, available surface area, load requirements and assembly design.
Materials & Finishes
Smooth body rivet nuts are available in steel, stainless steel, aluminum and brass.
Available finish options may include:
- CR3 white zinc
- Yellow zinc
- Black zinc
- Zinc-nickel
- Nickel plating
- Application-specific finishes
Steel provides strong and economical performance for general industrial applications. Stainless steel offers greater corrosion resistance, while aluminum provides a lightweight option. Brass may be selected for electrical conductivity, corrosion resistance or application compatibility.
Material and finish availability varies by thread size, flange style, application requirements and production quantity.
Smooth Body Rivet Nut Installation
Smooth body rivet nuts are installed into a properly sized round mounting hole using a manual, pneumatic, hydraulic or automated rivet nut installation tool.
The tool engages the internal thread and pulls the threaded section upward. This causes the body to collapse behind the panel, clamping the rivet nut securely to the material.
For reliable installation:
- Use the recommended round mounting hole size.
- Confirm that the material thickness is within the specified grip range.
- Use the correct mandrel and nosepiece for the thread size.
- Keep the rivet nut perpendicular to the mounting surface.
- Set the installation stroke or force for the selected part.
- Avoid oversized, irregular or damaged mounting holes.
- Test the installation in the actual application material before production.
Smooth body rivet nuts rely more heavily on correct hole size and installation settings than hex body designs. For applications requiring higher spin-out resistance, consider a knurled, half hex or full hex body rivet nut.
Typical Applications
Smooth body rivet nuts are commonly used where a reusable thread and one-sided installation are required.
Typical applications include:
- Sheet metal fabrication
- Electrical cabinets and enclosures
- Automotive panels and components
- HVAC equipment
- Appliances
- Electronic equipment
- Telecommunications equipment
- Metal furniture
- Machinery and industrial assemblies
- Housings and access panels
- Thin-wall tubing
- General manufacturing
Factory-Direct Supply & Custom Production
Imperial Rivets & Fasteners supplies factory-direct smooth body rivet nuts to OEMs, manufacturers, distributors and industrial assembly operations.
Small and large flange styles are available in standard inch and metric thread sizes. Steel, stainless steel, aluminum, brass and multiple finish options may be supplied depending on product and production requirements.
We can also support custom thread sizes, grip ranges, materials, finishes and dimensional specifications for volume production.
Select a standard part from the specification charts above and add it to your RFQ. For custom production, provide the thread size, panel thickness, mounting hole size, flange style, material, finish and estimated annual quantity.
Questions or Custom Requirements?
Contact our sales team at sales@imperialrivet.com or (630) 964-0208.
