MDIN 6926 Nylon-Insert Hex Flange Lock Nuts – Class 8 & 10, Clear Zinc Plated

DIN 6926 Nylon-Insert Hex Flange Lock Nuts – Class 8 & 10, Clear Zinc Plated

JUXIN FASTENERS supplies DIN 6926 nylon-insert hex flange lock nuts manufactured from carbon steel in property classes 8 and 10,

 with clear zinc plating, also described as blue-white zinc plating.

These industrial fasteners combine a non-metallic nylon locking insert with an integrated hexagonal flange to provide prevailing-torque resistance to rotational loosening and a broader bearing surface.

Common product names in North American and European industrial markets include nylon insert flange locknuts, 

nylon-insert hex flange nuts, prevailing torque flange lock nuts, DIN 6926 lock nuts, ISO 7043 flange nuts and vibration-resistant nylon locking nuts.

JUXIN supports OEM manufacturers, Tier-1 and Tier-2 suppliers, equipment builders, mechanical engineers, 

production managers and industrial procurement teams requiring standard or drawing-based fastening components.

Product Specifications

Engineering Note: The exact product configuration must be verified against the applicable standard edition and approved manufacturing drawing. 

Metric and inch-series products are separate specifications and must not be treated as dimensionally interchangeable.

Metric Sizes and ISO 7043 Dimensional Reference

DIN 6926 nylon-insert flange lock nuts are commonly specified in metric sizes from M5 through M20.

ISO 7043:2012 covers prevailing-torque hexagon nuts with flange and non-metallic inserts, with property classes 8, 9 and 10.

The following dimensional values provide preliminary engineering references for ISO 7043 configurations.

Dimensions are reference values associated with the ISO 7043 configuration. Final tolerances and manufacturing dimensions must follow the approved product drawing.

The overall nut height includes the integrated flange.

Important Dimensional Considerations

DIN 6926, ISO 7043 and related European specifications may differ in certain dimensions, including wrenching geometry.

For example, the M10 across-flats dimension must be confirmed before replacing an existing DIN or EN specification.

Customers should identify the exact standard, thread pitch, flange dimensions, nut height and required tolerances when requesting equivalent or replacement parts.

UNC and UNF Inch-Series Nylon-Insert Flange Lock Nuts

For North American industrial applications, nylon-insert flange lock nuts may also be specified using Unified National Coarse (UNC) or Unified National Fine (UNF) thread systems.

ASME B18.16.6 provides requirements for specified inch-series prevailing-torque lock nuts, including nylon-insert hex flange configurations.

The following thread sizes are commonly used as engineering references for North American fastening inquiries.

These are standard thread designations for technical reference and sourcing inquiries, not confirmation of stock availability for every size.

Metric and UNC/UNF threads are not interchangeable.

For inch-series inquiries, customers should provide the required thread designation, mechanical grade, flange geometry, surface finish and applicable ASME specification.

Class 8 vs. Class 10 Nylon-Insert Flange Lock Nuts

Class 8 – Medium-Strength Carbon Steel

Class 8 nylon-insert flange lock nuts are commonly used in medium-strength industrial fastening applications.

They may be selected for assemblies involving compatible property class 8.8 bolts, subject to the relevant joint design and mechanical requirements.

Typical applications include machinery brackets, equipment frames, electrical enclosures, HVAC equipment and general industrial assemblies.

Class 10 – High-Strength Carbon Steel

Class 10 nylon-insert flange lock nuts provide higher specified mechanical performance than Class 8 versions.

They are suitable for evaluation in higher-load assemblies using appropriately specified bolts and verified tightening procedures.

Potential applications include heavy machinery, industrial motors, pumps, mechanical drives and selected automotive assemblies.

Nut property class alone does not establish the strength of the completed bolted joint.

Engineers must verify proof load, bolt compatibility, thread engagement, preload and operating conditions.

Important: Inch-series nylon-insert lock nuts use separate mechanical grading requirements. 

Metric Class 8 and Class 10 must not be directly equated with ASME inch-series grades.

How Nylon-Insert Flange Lock Nuts Work

The nylon locking insert is positioned near the upper section of the nut.

During installation, the mating bolt thread enters and deforms the nylon insert, producing resistance to relative rotation.

This prevailing-torque mechanism helps resist rotational loosening caused by vibration and repeated mechanical movement.

The integrated flange provides a larger bearing surface than a conventional hex nut of comparable size.

Key Engineering Benefits

• Resistance to rotational loosening through prevailing torque.

• Integrated flange for broader bearing-load distribution.

• Potential elimination of a separate flat washer in suitable joints.

• Reduced loose-component handling during assembly.

• Compatibility with appropriately designed manual and automated installation processes.

• Availability in different metric mechanical property classes.

• Suitability for standard and custom OEM fastening programs.

Prevailing torque does not replace adequate joint preload. 

A poorly designed or improperly tightened joint may still loosen under severe vibration or transverse loading.

Clear Zinc Plating and Blue-White Zinc Surface Protection

Clear zinc plating is widely used for carbon steel industrial fasteners requiring corrosion protection and a bright metallic appearance.

In international fastener markets, similar finishes may be described as clear zinc plated, blue-white zinc plated, zinc plated with clear passivation or bright zinc plated.

The final appearance depends on the zinc coating and passivation process.

RoHS and Coating Compliance

For industrial OEM applications, coating specifications may require trivalent chromium passivation and compliance with applicable RoHS restrictions.

However, the appearance of a blue-white zinc coating does not independently prove RoHS compliance.

Customers should request coating documentation and restricted-substance declarations where required.

Corrosion Performance Considerations

Corrosion resistance depends on:

• Zinc coating thickness.

• Passivation chemistry.

• Supplementary sealers.

• Environmental exposure.

• Moisture and salt exposure.

• Installation damage.

• Contact with dissimilar metals.

• Coating friction characteristics.

Clear zinc plating is commonly suitable for controlled indoor and moderately exposed industrial environments when the coating specification meets the service requirements.

For severe outdoor, marine or chemically aggressive conditions, alternative protective coatings or materials may be necessary.

Clear Zinc vs. Yellow Zinc vs. Black Oxide

Clear Zinc / Blue-White Zinc

Provides a bright silver or slightly blue-white appearance with corrosion protection determined by the coating system.

Yellow Zinc

Provides a yellow or iridescent appearance. Corrosion performance depends on the specified passivation system, coating thickness and supplementary treatments.

Black Oxide

Primarily provides a dark surface appearance and generally offers limited corrosion protection without supplementary treatment.

Coating performance should be compared using verified specifications and testing rather than color alone.

Industrial Applications & Engineering Solutions

1. Automotive Fastening Systems

Nylon-insert hex flange lock nuts can be considered for automotive brackets, auxiliary equipment mounts, interior mechanical assemblies and selected vibration-exposed components.

The prevailing-torque feature helps resist rotational loosening, while the flange distributes bearing loads across suitable mating surfaces.

Automotive engineers should evaluate vibration, corrosion exposure, temperature, joint preload and assembly repeatability.

For OEM programs, quality requirements may include material traceability, coating specifications, inspection reports and customer-specific production approval.

Safety-critical automotive applications require separate engineering validation.

2. Electric Vehicles and EV Battery Pack Assemblies

Potential applications include EV battery enclosure brackets, cooling-system support structures, auxiliary equipment mounts and non-electrical mechanical assemblies.

The integrated flange can simplify fastening arrangements where bearing area and assembly efficiency are important.

EV battery engineers must evaluate electrical isolation, galvanic compatibility, temperature, vibration and environmental sealing requirements.

Standard nylon-insert flange lock nuts should not be assumed suitable for high-voltage electrical terminals, 

critical battery retention or high-temperature battery components without application-specific validation.

3. Rail Transit and Railway Equipment

Potential applications include railway equipment enclosures, interior mounting brackets, access panels and selected auxiliary assemblies.

Railway operating environments may involve repeated vibration, thermal cycling, corrosion and demanding maintenance requirements.

Engineers should verify prevailing-torque performance, material compatibility and relevant railway safety specifications.

The nylon insert may also require evaluation under applicable fire-performance requirements.

Ordinary industrial lock nuts are not automatically approved for safety-critical railway applications.

4. Aerospace Ground Support and Aviation Equipment

Potential applications include non-flight-critical ground support equipment, workshop machinery, maintenance fixtures and auxiliary industrial assemblies.

Aircraft-installed fastening systems require approved aerospace specifications, traceability and engineering authorization.

Standard DIN 6926 industrial lock nuts must not be represented as aerospace-certified fasteners.

5. Electrical Cabinets and Power Distribution Equipment

Potential applications include electrical cabinet frames, power distribution enclosure brackets, control panel supports and equipment mounting structures.

The integrated flange provides a broader bearing surface for suitable mechanical connections.

Engineers must independently verify grounding continuity, protective coating compatibility, electrical clearance and bonding requirements.

A nylon-insert flange lock nut does not automatically provide an approved electrical grounding connection.

6. HVAC and Ventilation Equipment

Nylon-insert flange lock nuts may be used in suitable fan supports, ventilation equipment frames, duct brackets, mechanical housings and HVAC mounting assemblies.

The integrated flange may reduce separate washer handling and simplify assembly processes.

Service temperature, vibration, moisture exposure and maintenance requirements must be considered.

7. Industrial Machinery, Pumps and Motors

Applications may include machinery brackets, pump supports, motor mounts, conveyor structures, protective guards and equipment frames.

Class 8 and Class 10 options support different mechanical performance requirements.

Engineers should consider dynamic loads, vibration, joint stiffness, preload and service temperature.

8. Robotics and Industrial Automation

Potential applications include automation frames, robot-cell guarding, actuator brackets, tooling supports and auxiliary mechanical mounting structures.

Repeated movement and cyclic loading can increase the importance of joint preload and resistance to rotational loosening.

Production engineers should verify thread quality, coating friction, installation torque and fastening repeatability.

9. Sheet Metal Fabrication and Metal Enclosures

The integrated flange can provide increased bearing area when fastening suitable sheet-metal brackets, enclosure frames and fabricated components.

Design engineers should check hole size, sheet thickness, edge distance, local deformation and flange seating.

For blind-side installation, blind rivet nuts or self-clinching fasteners may be more suitable.

10. Construction Machinery and Equipment

Potential applications include equipment guards, mounting brackets, mechanical support structures and selected construction machinery components.

The fastening system must be evaluated for dynamic loading, environmental exposure and maintenance requirements.

Structural or safety-critical connections governed by specific construction standards require approved fastening systems.

11. Medical Equipment and Laboratory Machinery

Potential applications include approved non-patient-contact instrument brackets, laboratory machinery frames, equipment enclosures and auxiliary mounting structures.

Engineers must evaluate cleanliness, cleaning chemicals, corrosion, temperature and applicable regulatory requirements.

Ordinary clear zinc plated carbon steel lock nuts are not inherently medical-grade, sterile or suitable for implantable applications.

Installation and Assembly Engineering Guidelines

Thread Compatibility

Confirm the correct nominal diameter, thread pitch, thread tolerance and mechanical property requirements.

Metric coarse, metric fine, UNC and UNF threads must not be mixed.

Tightening Torque and Joint Preload

Nylon-insert lock nuts generate prevailing torque during installation.

The tightening procedure must account for the prevailing-torque component and the torque required to establish the intended clamp load.

Coating friction, lubrication, bolt strength and clamped material characteristics influence the relationship between applied torque and achieved preload.

Generic tightening torque values should not be used without considering the actual joint design.

Nylon Insert Engagement

The mating bolt must engage the nylon insert sufficiently to establish the required prevailing-torque function.

Thread engagement and bolt protrusion should follow the applicable specification and approved assembly drawing.

Reusability and Maintenance

Nylon-insert flange lock nuts may be reusable when permitted by the relevant specification and when locking performance remains acceptable.

Repeated installation and removal can reduce prevailing torque.

Nuts with damaged inserts, worn threads or insufficient locking resistance should be replaced.

Operating Temperature

The nylon insert limits the permissible service temperature of the complete fastening system.

High-temperature applications may require all-metal prevailing-torque lock nuts or another engineered locking method.

Confirm the actual insert material and temperature capability before selection.

Flange Bearing Surface

Ensure that the flange seats correctly against the mating surface.

Inspect for burrs, excessive hole clearance, deformation, unsuitable coatings and interference with adjacent components.

The integrated flange does not automatically replace a hardened washer or specialized bearing arrangement in every application.

OEM Quality Control and Inspection Requirements

For repeatable industrial production, quality planning may include:

• Material grade verification.

• Chemical composition verification where specified.

• Mechanical property and proof-load testing.

• Thread gauge inspection.

• Across-flats dimensional inspection.

• Overall height and flange diameter verification.

• Nylon insert integrity inspection.

• Prevailing-torque testing.

• Zinc plating thickness inspection.

• Corrosion testing against approved requirements.

• Surface appearance verification.

• Lot identification and traceability.

• Packaging and shipment inspection.

Relevant technical references may include ISO 898-2, ISO 2320, ISO 4042 and applicable product standards.

Inspection methods, acceptance criteria and sampling plans should be defined according to the applicable specification and customer requirements.

DIN 6926, ISO 7043 and ASME B18.16.6 Standards Comparison

DIN 6926

A widely recognized legacy designation for metric nylon-insert hex flange lock nuts.

ISO 7043

An international standard for metric coarse-thread prevailing-torque hexagon nuts with flange and non-metallic inserts.

DIN EN 1663

A European standard associated with metric coarse-thread prevailing-torque hex flange nuts with non-metallic inserts.

ISO 12125

An international standard covering specified metric fine-thread prevailing-torque hex flange nuts with non-metallic inserts.

DIN EN 1666

A European fine-thread nylon-insert hex flange nut standard.

ASME B18.16.6

A United States standard covering specified inch-series prevailing-torque lock nuts, including nylon-insert hex flange configurations.

NF E 25-413, NF E 25-506 and NF E 25-507

French national standard references encountered in fastener specifications. 

Their exact product scope, edition and relationship to the requested nut must be verified before being used as equivalent standards.

Important: These standards must not be presented as universally interchangeable.

 Dimensions, mechanical properties, thread systems and testing requirements must be confirmed before substitution.

Custom OEM Nylon-Insert Flange Lock Nut Solutions

JUXIN FASTENERS supports technical review of standard and customized industrial fastening requirements.

Potential customization areas include:

• Metric coarse and fine-thread configurations.

• UNC and UNF inch-series inquiries.

• Carbon steel property classes 8 and 10.

• Clear zinc and alternative specified coatings.

• Customized flange dimensions.

• Special nut heights and wrenching geometry.

• Application-specific prevailing-torque requirements.

• Customer-defined inspection documentation.

• Industrial bulk packaging.

• Drawing-based OEM production programs.

Custom configurations are subject to technical feasibility, tooling requirements, order quantity and approval of the final manufacturing drawing.

Frequently Asked Questions

What is a DIN 6926 nylon-insert hex flange lock nut?

It is a hexagonal flange nut incorporating a non-metallic insert that produces prevailing torque against the mating bolt thread. 

The integrated flange provides a broader bearing surface.

Is DIN 6926 equivalent to ISO 7043?

They describe closely related metric nylon-insert flange lock nut configurations, but dimensional differences may exist. 

Confirm the applicable edition and approved drawing before substitution.

What is the difference between Class 8 and Class 10?

Class 10 provides higher specified mechanical performance than Class 8. Selection must consider bolt compatibility, proof load, preload and operating conditions.

What is the difference between clear zinc and blue-white zinc plating?

These terms are commonly used for bright zinc-plated finishes with clear or slightly blue-white appearance. 

Exact coating chemistry and corrosion performance depend on the specified process.

Is clear zinc plating RoHS compliant?

It can be specified using RoHS-compliant coating systems, but compliance must be verified through the actual plating specification and supporting documentation.

Are clear zinc plated lock nuts suitable for outdoor use?

Suitability depends on coating thickness, passivation, environmental exposure and corrosion testing. 

Severe outdoor conditions may require enhanced protection.

Can metric DIN 6926 nuts replace UNC or UNF nuts?

No. Metric and Unified thread systems are different and must not be interchanged.

Can nylon-insert flange lock nuts be reused?

Reuse may be permitted when the applicable specification allows it and the nut continues to meet the required prevailing-torque criteria.

Can nylon-insert lock nuts be used at high temperatures?

The nylon insert has temperature limitations. 

The insert material and complete fastening system must be evaluated for the actual service conditions.

What information is required for an OEM quotation?

Customers should provide the thread designation, applicable standard, mechanical property class, coating, 

dimensions, estimated order quantity, technical requirements and drawings where available.

Request a Quote – DIN 6926 Clear Zinc Plated Nylon-Insert Hex Flange Lock Nuts

JUXIN FASTENERS supplies industrial fastening components for OEM manufacturers, 

Tier-1 and Tier-2 suppliers, machinery builders, engineering teams, production managers and global procurement organizations.

For an accurate technical and commercial quotation, please provide:

1. Required DIN, ISO, EN or ASME standard.

2. Metric or UNC/UNF thread designation.

3. Required mechanical property class or grade.

4. Material and surface coating specification.

5. Flange dimensions, nut height and tolerances.

6. 2D engineering drawings or 3D CAD files, if available.

7. Prevailing-torque and inspection requirements.

8. Estimated annual consumption and purchase quantity.

9. Packaging, documentation and delivery requirements.

Our team can review standard and customized fastener requirements and provide quotation support for suitable industrial production programs.

Email: info@juxinfasteners.com

Website: www.juxinfasteners.com

JUXIN FASTENERS – Industrial Lock Nuts, OEM Fastening Components and Custom Engineered Fastener Solutions.

Packaging Standard

At Juxin Fasteners, we apply standardized export packaging to ensure product protection, traceability, and compliance with international logistics requirements.

1. Standard Export Packaging

Unless otherwise specified, all products will be packed according to our factory standard export packaging, which includes:

Moisture-resistant inner protection

Poly bag or small box packing as required

Reinforced export cartons

Clear labeling with part number, specification, batch number, and quantity

Palletizing for sea or air shipment when necessary

Our standard packaging is designed to ensure safe transportation, efficient warehousing, and long-distance international shipping.

2. Customized Packaging Options

We also provide customized packaging solutions according to customer requirements, including but not limited to:

Private labeling

Customized barcodes

Specific carton dimensions

Retail packaging

Special pallet configuration

Customer-specific marking and identification

So that you know, customized packaging may involve additional costs and extended lead time depending on the complexity of the requirements.

3. Compliance & Quality Assurance

All packaging processes are controlled under our ISO 9001 quality management system to ensure consistency, traceability, and product integrity throughout the supply chain.