Flat Head Open-End Half-Hex Blind Rivet Nuts – Blue Zinc Steel

Anti-Rotation Partial Hex Threaded Inserts for Industrial Sheet Metal and OEM Assemblies

JUXIN FASTENERS provides flat head open-end half-hex blind rivet nuts for creating reusable internal threads in thin sheet metal, fabricated enclosures, 

hollow sections, and industrial equipment assemblies where installation access is available from only one side.

These steel threaded inserts feature a partially hexagonal body designed to engage with a matching non-round mounting hole. 

The mechanical engagement helps resist insert rotation during bolt tightening, removal, and repeated servicing.

The flat head provides a bearing surface against the panel, 

while the open-end configuration allows a mating screw to extend through the insert when adequate clearance is available behind the workpiece.

Also known as open-end half-hex rivet nuts, partial hex blind rivet nuts, hex-body nutserts, and blind threaded inserts, 

these fasteners provide an alternative to welded nuts, loose nuts, and directly tapped threads in applications where those methods are unsuitable.

The standard product family includes metric sizes M3, M4, M5, M6, M8, and M10, with a stated series grip range of 0.5–4.0 mm.

Key Product Features

• Half-Hex Body: Provides geometric anti-rotation engagement with a correctly formed mounting hole.

• Open-End Design: Allows a mating screw to pass through the insert, subject to backside clearance.

• Flat Head: Provides a relatively broad bearing area around the installation hole.

• Steel Construction: Supports mechanically robust threaded connections when properly selected and installed.

• Blue Zinc Finish: Provides sacrificial corrosion protection for the steel substrate.

• Single-Sided Installation: Suitable for enclosed structures where the opposite side cannot be accessed.

• Cold-Forming Installation: Eliminates the need to weld a nut to the panel.

• Reusable Internal Threads: Supports equipment assembly, disassembly, and maintenance.

• OEM Customization: Special dimensions, thread specifications, coatings, and packaging can be evaluated against customer drawings.

Why Choose a Half-Hex Blind Rivet Nut?

1. Mechanical Anti-Rotation Engagement

A conventional round-body rivet nut generally relies on friction and mechanical retention generated during the setting process.

A half-hex rivet nut uses a partially hexagonal body section that engages with a corresponding non-round mounting hole.

This geometry provides a mechanical resistance path against rotation, which is particularly useful when the installed threaded insert is subjected to repeated tightening and loosening.

However, anti-rotation performance is not determined by body geometry alone.

Important engineering variables include:

• Hexagonal hole dimensions and tolerances

• Host panel material and hardness

• Grip range and actual panel thickness

• Insert wall thickness and body geometry

• Installation stroke or setting force

• Mating screw thread and tightening torque

• Surface condition and coating thickness

The installed joint should be tested under representative assembly conditions to establish its actual spin-out torque.

2. Open-End Design for Screw Penetration

Unlike a closed-end rivet nut, an open-end blind rivet nut does not have an enclosed barrel at the back of the internal thread.

This allows a mating screw or threaded stud to extend beyond the insert where the assembly provides sufficient clearance.

For design engineers, this can be advantageous when the screw length is determined by multiple stacked components or when the assembly requires greater thread penetration flexibility.

The screw must still provide sufficient thread engagement without interfering with adjacent components.

An open-end rivet nut should not be selected where the application requires the rear thread cavity to be enclosed against contamination unless additional protection is provided.

3. Flat Head for Panel Bearing Support

The flat head, also described as a large flange in some product catalogs, provides a bearing surface against the host panel.

This helps distribute the applied load around the mounting hole and can reduce the risk of localized deformation when the joint is correctly designed.

The flange also contributes to resistance against the insert being pushed through the panel.

Actual push-out resistance depends on the flange diameter, panel properties, installation geometry, and joint loading.

4. Threaded Connections Without Welding

Thin sheet metal may not provide sufficient thread engagement for direct tapping.

Welded nuts can introduce heat, distortion, additional processing, and accessibility challenges.

Half-hex blind rivet nuts provide an alternative method of creating an internal thread without applying welding heat to the workpiece.

The insert is placed into a correctly prepared mounting hole and installed using a compatible rivet nut setting tool.

During installation, the designated deformable portion of the insert forms a retaining bulge behind the panel.

This creates a mechanically retained threaded connection accessible from the front side.

Product Specifications

Note: The stated grip range describes the product family. Individual thread sizes and body configurations may have different grip ranges. Final dimensions should be confirmed against the approved specification drawing.

Engineering Applications

Electrical Cabinets and Control Panels

Half-hex blind rivet nuts can provide reusable threaded mounting points for electrical cabinets, control enclosures, equipment brackets, and removable access panels.

These applications often involve relatively thin steel panels where welding may introduce distortion or damage a pre-finished surface.

The half-hex body helps resist rotation during installation and subsequent maintenance.

Typical applications include:

• Electrical control cabinet mounting brackets

• Distribution enclosure assemblies

• Internal equipment support rails

• Removable service panels

• Fan and accessory mounting brackets

• Industrial control equipment housings

Where a fastening point forms part of an electrical bonding or protective grounding system, electrical continuity must be verified separately.

Automotive and Commercial Vehicle Equipment

Open-end half-hex rivet nuts may be considered for non-safety-critical brackets, interior equipment housings, serviceable panels, and fabricated sheet metal components.

They provide an alternative to welded nuts when backside access is restricted.

Vibration resistance, thread engagement, joint preload, and fatigue performance must be evaluated for the specific application.

Industrial Machinery and Automation Equipment

Industrial machines frequently incorporate removable covers, guards, equipment housings, and mounting brackets.

A reusable threaded insert allows maintenance personnel to remove and reinstall fasteners without accessing the opposite side of the panel.

The anti-rotation geometry can be beneficial where repeated service operations might otherwise loosen a conventional round-body insert.

HVAC and Mechanical Equipment

Potential applications include ventilation housings, equipment access panels, mounting brackets, and serviceable mechanical enclosures.

For equipment exposed to condensation or corrosive environments, coating selection and environmental suitability require separate evaluation.

Sheet Metal Fabrication and OEM Equipment

Half-hex blind rivet nuts are suitable for evaluation in:

• Fabricated sheet metal housings

• Hollow steel profiles

• Equipment frames

• Industrial furniture components

• Instrument housings

• Control panel assemblies

• Mechanical support brackets

The correct insert must be selected according to panel thickness, material, hole geometry, and required mechanical performance.

Open-End Half-Hex vs. Closed-End Half-Hex Rivet Nuts

Engineering Selection Guidance

Choose the open-end configuration when the assembly requires screw penetration flexibility and does not require an enclosed rear thread cavity.

Choose the closed-end configuration when limiting direct contamination through the back of the threaded insert is important.

Neither configuration should be assumed watertight without validation of the complete installed joint.

Metric and Inch Thread Options for International OEM Programs

The documented standard product family uses metric threads from M3 to M10.

For North American OEM projects, JUXIN FASTENERS can evaluate customer drawings specifying Unified inch threads.

Common requested Unified thread designations include:

• #6-32 UNC

• #8-32 UNC

• #10-24 UNC

• 1/4-20 UNC

• 5/16-18 UNC

• 3/8-16 UNC

These are reference thread designations for custom inquiry evaluation, not confirmed stock sizes for this product.

Metric thread geometry may be specified using applicable ISO standards, while Unified threads may be specified according to ASME B1.1.

A metric rivet nut must not be treated as interchangeable with an inch-thread rivet nut merely because the nominal diameters appear similar.

The thread system, pitch, mating screw, mounting hole, body dimensions, and setting tool must all be compatible.

Blue Zinc Plating and Corrosion Protection

The blue zinc-plated finish provides sacrificial corrosion protection for the steel insert.

The coating specification should be defined by measurable requirements rather than visual appearance alone.

Relevant coating specifications may include ISO 2081 and ASTM B633, subject to the selected plating process.

For OEM purchasing and qualification, specify:

• Required zinc coating thickness

• Passivation chemistry

• Restricted-substance requirements

• Corrosion resistance criteria

• Coating appearance

• Hydrogen embrittlement risk controls where applicable

• Inspection and acceptance requirements

Where RoHS compliance is required, the plating chemistry and relevant supporting documentation should be confirmed for the actual production batch.

Custom Half-Hex Rivet Nuts for OEM Manufacturing

JUXIN FASTENERS supports drawing-based technical review for custom industrial fastening applications.

Customer requirements may include:

• Non-standard thread sizes

• Unified inch threads

• Modified flange dimensions

• Special partial hexagonal body geometry

• Alternative grip ranges

• Special barrel lengths

• Customer-specified surface treatments

• Inspection requirements

• Production packaging and labeling

• Scheduled OEM purchasing programs

Manufacturing feasibility, minimum order quantities, tooling, and delivery schedules depend on the approved technical requirements.

Request an OEM Quotation

For engineering evaluation, new supplier qualification, and production sourcing, please send:

1. Required metric or inch thread size

2. Technical drawing or CAD file

3. Panel material and thickness

4. Installation hole dimensions

5. Required grip range

6. Mechanical performance requirements

7. Coating specification

8. Estimated order quantity

9. Annual demand forecast

10. Packaging and inspection requirements

JUXIN FASTENERS can review the submitted requirements and prepare a quotation based on the confirmed product configuration.

JUXIN FASTENERS

Email: info@juxinfasteners.com

Website: www.juxinfasteners.com

Contact: https://www.juxinfasteners.com/contact-us/