Countersunk Head Open-End Smooth Body Steel Blind Rivet Nuts

Technical Specifications — Countersunk Open-End Steel Blind Rivet Nuts

Product Identification：

Metric Thread Specifications

The following are ISO metric coarse thread designations.

Relevant thread references include ISO 261, ISO 724, and ISO 965.

The actual thread tolerance class must be established by the approved product drawing.

Unified Inch Thread Options for US OEM Projects

Unified inch threads may be evaluated for customer-specific drawings.

These are potential custom thread requirements, not confirmed standard sizes for this product.

Unified thread requirements should reference ASME B1.1.

Metric and Unified threads are not interchangeable.

Grip Range Conversion Reference

The published product-series grip range is 0.5–5.0 mm.

These figures are dimensional conversions only.

Individual rivet nut sizes may have different permissible grip intervals.

Countersink Geometry and Flush Installation

1. Countersink Included Angle

Countersunk rivet nuts require the mounting recess to match the head geometry.

Depending on the product design, the countersink may use a 90°, 100°, or another specified included angle.

The exact angle must be taken from the approved rivet nut drawing.

Do not select the angle solely from whether the thread is metric or Unified inch.

2. Countersink Depth

The countersink depth must allow the rivet nut head to seat at the specified height relative to the panel surface.

Insufficient depth may leave the flange protruding.

Excessive depth can reduce support beneath the head and may affect installation stability.

3. Remaining Panel Thickness

Countersinking removes material from the mounting panel.

For thin sheet metal, this reduction can influence pull-through resistance, panel deformation, and joint reliability.

Engineers should verify that the remaining material provides sufficient support for the installed fastener.

4. Mounting Hole Diameter

The hole diameter must match the selected rivet nut design.

Oversized holes can reduce mechanical engagement and spin-out resistance.

Undersized holes can interfere with insertion or damage the protective coating.

Use the hole diameter and tolerance stated on the approved drawing.

5. Head Seating and Surface Flatness

The countersunk flange should seat consistently against the prepared mounting surface.

Uneven seating may affect joint alignment, load distribution, and mating-component clearance.

For applications requiring a precisely flush mounting surface, the acceptable installed head height should be defined in the inspection specification.

Open-End Versus Closed-End Designs

Open-end rivet nuts allow the mating screw to extend through the insert.

Closed-end rivet nuts enclose the threaded cavity at the blind end.

Open-end designs may offer greater flexibility for screw penetration, provided backside clearance is available.

Closed-end designs may be preferred when limiting direct contamination of the thread cavity is important.

Neither configuration should be assumed to provide a fully sealed assembly without appropriate design validation.

Smooth Body Versus Knurled Body

Smooth body rivet nuts rely on the installed deformation and contact with the mounting material to resist movement.

Knurled designs incorporate external engagement features that can improve rotation resistance under suitable conditions.

The appropriate design depends on:

• Panel material

• Mounting hole tolerance

• Installation force

• Grip range

• Required spin-out torque

• Axial pull-out load

• Joint vibration conditions

For high-load or vibration-sensitive assemblies, mechanical testing is recommended.

Surface Treatment and Corrosion Requirements

The standard product description specifies blue-white zinc-plated steel.

Zinc electroplating specifications may be defined using relevant ASTM B633 or ISO coating standards, subject to customer requirements.

A complete OEM coating specification should identify:

• Zinc coating type

• Minimum coating thickness

• Passivation system

• Corrosion test requirements

• Restricted-substance requirements

• Acceptance criteria

Coating color alone does not establish compliance with RoHS, REACH, or a specific corrosion resistance level.

Installation Procedure

1. Review the approved rivet nut drawing.

2. Verify thread size, grip range, and mounting material thickness.

3. Prepare the mounting hole to the specified diameter.

4. Machine or form the countersink to the approved angle and depth.

5. Remove excessive burrs and inspect the hole.

6. Select a compatible rivet nut setting tool and mandrel.

7. Thread the rivet nut onto the installation mandrel.

8. Insert the rivet nut into the prepared countersunk hole.

9. Confirm correct flange seating.

10. Maintain the setting tool perpendicular to the mounting surface.

11. Apply the approved installation stroke or setting force.

12. Release the tool without damaging the internal thread.

13. Inspect the installed head position and backside deformation.

14. Verify the installation against the specified mechanical requirements.

Manual, pneumatic, hydraulic, or automated installation equipment may be used where compatible with the selected fastener.

A compatible rivet nut setting tool is required; the product should not be described as requiring no special installation tooling.

OEM Performance Validation

Depending on the application, engineering verification may include:

• Countersink angle and depth

• Mounting hole diameter

• Installed head height

• Flange seating

• Backside deformation

• Spin-out torque

• Axial pull-out resistance

• Push-out resistance

• Thread integrity

• Screw engagement

• Panel deformation

• Repeated assembly performance

• Corrosion resistance

• Vibration performance where required

Acceptance limits should be defined by the OEM drawing or approved qualification plan.

Technical Drawings and CAD

The existing product documentation refers to specification PDF pages 93–94 and associated CAD information.

Before production approval, confirm the correct drawing revision and dimensional data for:

• Head diameter

• Countersink angle

• Countersink depth

• Body diameter

• Overall length

• Thread engagement

• Mounting hole diameter

• Grip range

• Installation dimensions

Custom sizes and configurations can be reviewed against customer-supplied technical drawings.

OEM RFQ Checklist

For engineering review and quotation, please provide:

• Metric or Unified inch thread

• 2D technical drawing or 3D CAD model

• Countersink angle

• Countersink diameter

• Countersink depth

• Mounting hole diameter and tolerance

• Panel material and thickness

• Required grip range

• Available backside clearance

• Required flushness tolerance

• Mating screw specification

• Installation method

• Spin-out and pull-out requirements

• Surface treatment specification

• Corrosion resistance requirements

• Initial order quantity

• Annual purchasing forecast

• Inspection documentation requirements

• Packaging and delivery requirements

Why Use Countersunk Blind Rivet Nuts?

Countersunk blind rivet nuts are selected when an assembly requires a threaded fastening point without a protruding conventional rivet nut flange.

Unlike a large-flange rivet nut, a countersunk design requires a prepared recess in the mounting material.

When the countersink geometry matches the rivet nut head, the installed flange can sit level with the surrounding panel surface.

This can be valuable where surface clearance, appearance, or mating-component positioning is important.

Typical applications include:

• Sheet metal equipment panels

• Automotive interior brackets

• Electrical enclosure assemblies

• Machinery covers

• Instrument housings

• Industrial access panels

• Metal furniture components

• Transportation equipment interiors

• Fabricated structural profiles used in non-critical assemblies

Flush-Mount Installation: What Engineers Must Consider

A countersunk rivet nut does not automatically produce a flush surface.

Correct seating depends on the relationship between the countersunk head and the prepared mounting hole.

Engineers should verify:

• Countersink included angle

• Countersink major diameter

• Countersink depth

• Pilot hole diameter

• Remaining material thickness

• Flange seating condition

• Rivet nut grip range

• Installation stroke

• Panel deformation

An incorrectly prepared countersink can cause the head to remain proud of the surface or sit excessively below it.

Both conditions may affect assembly fit and mechanical retention.

Metric and Unified Inch Countersink Designs

Metric and Unified inch thread requirements are commonly encountered in international OEM sourcing.

However, thread system and countersink angle are separate design parameters.

Some product families use 90° countersink geometry, while other designs may specify 100° or different head configurations.

The appropriate angle must always be determined from the actual rivet nut drawing.

A metric thread does not automatically guarantee a 90° head, and an inch thread does not automatically require a 100° head.

For replacement or cross-sourcing projects, the existing mounting hole geometry must be checked before approving an alternative rivet nut.

Open-End Design for Screw Engagement Flexibility

The open-end barrel allows a mating screw to pass through the threaded portion of the rivet nut.

This may be advantageous where additional screw penetration is needed or where different joint stack thicknesses are used.

However, sufficient backside clearance must be available.

Open-end rivet nuts do not provide the enclosed rear cavity of closed-end inserts.

For applications requiring contamination protection or fluid sealing, engineers should evaluate closed-end or specially sealed fastening alternatives.

Smooth Body Versus Knurled Body Rivet Nuts

This product uses a smooth cylindrical body.

Smooth body rivet nuts may be appropriate where the installation hole and setting conditions provide sufficient mechanical retention.

Knurled or ribbed body alternatives are designed to increase mechanical engagement with the surrounding material.

The choice should be based on required spin-out torque, panel material, hole tolerance, and installation conditions.

For higher torque requirements, an appropriately designed knurled or hex-body rivet nut may be more suitable.

Actual retention performance must be verified through testing.

Industrial Applications

Automotive and Transportation

Potential uses include interior equipment mounting, access panels, trim support structures, and selected fabricated brackets.

Electrical and Electronic Enclosures

Countersunk threaded inserts can provide reusable mounting points where protruding fastener heads would interfere with internal equipment or mating covers.

Industrial Machinery

Applications may include removable machine guards, equipment covers, maintenance panels, and fabricated assemblies.

HVAC and Appliance Manufacturing

Flush-mount inserts may be useful for ventilation equipment housings, appliance panels, and serviceable sheet metal assemblies.

Metal Furniture and Architectural Equipment

Countersunk rivet nuts can help maintain a clean mounting surface in cabinets, fixtures, fabricated metal furniture, and selected architectural components.

Rail and Commercial Vehicle Interiors

They may be evaluated for selected non-structural interior fittings and removable panel connections, subject to project-specific qualification.

OEM Sourcing and Engineering Support

JUXIN FASTENERS supports drawing-based sourcing requirements for countersunk steel rivet nuts and customized threaded inserts.

For engineering teams, critical information includes countersink geometry, panel thickness, installation hole dimensions, grip range, and retention requirements.

For procurement managers, strategic sourcing teams, and supplier development professionals, important requirements include approved drawings, annual demand, 

surface finish specifications, inspection documentation, and packaging requirements.

Request an OEM Quotation

Contact JUXIN FASTENERS for countersunk blind rivet nuts, custom threaded inserts, metric and Unified inch thread inquiries, and industrial bulk purchasing requirements.

JUXIN FASTENERS

Email: info@juxinfasteners.com

Website: www.juxinfasteners.com

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

Please provide your drawing, thread size, panel thickness, countersink requirements, installation conditions, and estimated order quantity.

Industrial Export Packaging — Countersunk Steel Blind Rivet Nuts

Standard Packaging

JUXIN FASTENERS provides industrial export packaging for countersunk open-end steel blind rivet nuts.

The standard packaging arrangement includes protective plastic inner bags, outer cartons, and palletized shipment where required.

Packaging arrangements are selected according to product dimensions, order quantities, handling conditions, and transportation requirements.

Reference Packaging Dimensions

These are reference packaging dimensions. Actual packaging quantities and shipment configurations are confirmed according to the purchase order.

Product Protection

Packaging can be arranged to help protect the fasteners against handling damage, unwanted moisture exposure, and coating abrasion during transportation.

Protective arrangements may include:

• Plastic inner bags

• Reinforced export cartons

• Moisture-resistant protection where required

• Product identification labels

• Part number and specification marking

• Batch and quantity labels

• Palletized packaging for international shipment

Customized OEM Packaging

Customer-specific packaging requirements can be reviewed, including:

• Private labeling

• Customer part-number labels

• Barcode identification

• Customized carton sizes

• Specified quantities per bag or carton

• Special pallet configurations

• Customer-specific traceability markings

Special packaging arrangements may affect pricing and lead time.

Industrial Purchasing and Supply Chain Requirements

For OEM and industrial procurement programs, JUXIN FASTENERS can review:

• Bulk order quantities

• Annual demand forecasts

• Customer-specific packaging specifications

• Product identification requirements

• Batch traceability

• Inspection documentation

• Shipping and delivery arrangements

Final packaging specifications and commercial terms are confirmed during quotation and purchase order review.

Contact JUXIN FASTENERS

For countersunk blind rivet nuts, custom threaded inserts, and OEM bulk purchasing requirements:

Email: info@juxinfasteners.com

Website: www.juxinfasteners.com

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