Brass Nylon-Insert Hex Lock Nuts | Metric & Inch Threads

Brass Nylon-Insert Hex Lock Nuts

Conductive, Nonmagnetic Brass Prevailing-Torque Nuts for OEM Manufacturing

Juxin Fasteners manufactures brass nylon-insert hex lock nuts for electrical equipment, instrumentation, industrial machinery, control cabinets and custom OEM fastening assemblies.

These locknuts combine an internally threaded brass hexagonal body with a retained non-metallic locking insert. 

During installation, the insert engages the mating screw or bolt thread, generating prevailing torque that helps resist unintended nut rotation.

Brass offers useful electrical conductivity, generally nonmagnetic behavior and corrosion resistance in many indoor and moderately moist environments.

These properties distinguish brass nylon-insert locknuts from conventional carbon steel and stainless steel alternatives.

Juxin Fasteners is an industrial fastener manufacturer supporting standard and custom-engineered fastening components. 

Our manufacturing capabilities include cold heading, cold forming, CNC machining and product-specific secondary operations selected according to the geometry, material, tolerances and production requirements of each project.

Product Specifications

The exact nut height, brass alloy, insert composition, dimensional tolerances and performance requirements must be confirmed against the approved engineering drawing.

What Is a Brass Nylon-Insert Locknut?

A brass nylon-insert locknut is a hexagonal internally threaded brass fastener containing a retained polymer locking insert.

As the mating bolt advances through the nut, its threads engage the insert and create frictional resistance.

This resistance is known as prevailing torque.

The locking feature helps resist nut rotation independently of the friction generated at the clamped bearing surface.

The brass body provides mechanical fastening capability and electrical conductivity, while the polymer insert provides the prevailing-torque locking function.

The insert does not make the entire nut electrically insulating.

How the Nylon Insert Locking Mechanism Works

1. Metallic Thread Engagement

The mating bolt initially engages the internal brass thread.

2. Insert Contact

As installation continues, the bolt enters the non-metallic locking insert.

3. Elastic Deformation

The insert deforms around the mating thread and creates contact pressure.

4. Prevailing Torque

Friction between the insert and bolt resists rotation.

5. Joint Tightening

The nut is tightened according to the specified assembly procedure.

Installation torque must account for both prevailing torque and the torque required to establish the intended joint preload.

Why Choose Brass Nylon-Insert Locknuts?

Electrical Conductivity

Brass is an electrically conductive metal and is widely used in electrical and electronic components.

Brass nylon-insert locknuts may be suitable for mechanical connections in electrical equipment where conductive metal hardware is preferred.

However, the presence of a conductive brass body does not establish the electrical resistance or bonding performance of a completed joint.

Electrical continuity must be evaluated where required.

Generally Nonmagnetic Material

Common brass alloys are generally nonmagnetic.

This characteristic can be useful for instrumentation and equipment where ferromagnetic fastening materials are undesirable.

The magnetic properties of the complete assembly should be verified where magnetic sensitivity is critical.

Corrosion Resistance

Brass provides corrosion resistance in many atmospheric and moderately moist environments.

However, brass is not universally resistant to all chemicals or aggressive service conditions.

Some brass alloys may be susceptible to dezincification or stress-corrosion cracking under particular conditions.

Material selection should reflect the actual environment.

Prevailing-Torque Locking

The nylon insert provides resistance to unintentional rotation under suitable operating conditions.

Its performance depends on insert material, thread fit, installation history and operating temperature.

Metric Brass Nylon-Insert Locknut Sizes

The identified metric product range includes M4, M5, M6, M8, M10 and M12.

The table provides standard ISO metric coarse-thread references.

Actual thread pitch, tolerance and nut dimensions must match the approved product specification.

Unified Inch-Thread Brass Nylon Locknuts

The identified inch-thread product range includes:

Additional Unified thread designs may be evaluated for custom OEM manufacturing.

Examples include:

Additional thread designations are engineering references for potential custom projects, not confirmed inventory.

Metric and Unified inch threads are not interchangeable. Matching approximate diameters does not establish thread compatibility.

Brass Alloy Selection for OEM Locknuts

The brass alloy affects mechanical properties, corrosion behavior, machinability and manufacturing feasibility.

Depending on the application, engineers may evaluate suitable brass alloys such as:

• C36000 free-machining brass

• C26000 cartridge brass

• CW614N brass

• Other customer-specified brass grades

These are possible material references, not a declaration that every alloy is used for this product.

Material selection must account for the nut geometry, manufacturing method, mechanical loading and applicable environmental requirements.

Different brass alloys should not be assumed to have identical mechanical properties.

Brass Nylon Locknuts vs. Stainless Steel Nylon Locknuts

The final choice depends on the electrical, mechanical and environmental requirements of the assembly.

Brass Nylon Locknuts vs. Carbon Steel Nylon Locknuts

Carbon steel locknuts are commonly selected where specified strength and cost are primary considerations.

Brass locknuts may be preferred where electrical conductivity, generally nonmagnetic behavior or compatibility with other brass components is important.

Neither material should be substituted without verifying the joint requirements.

Brass Nylon Locknuts vs. Brass Hex Nuts

A conventional brass hex nut relies primarily on joint preload and friction to resist rotation.

A brass nylon-insert locknut adds a prevailing-torque locking feature.

This can be beneficial where resistance to unintentional nut rotation is required.

However, a nylon-insert locknut is not automatically suitable for every vibration environment.

Brass Nylon Locknuts vs. Brass Nylon-Insert Flange Nuts

A conventional brass nylon-insert hex locknut has a hexagonal body without an integral flange.

A brass nylon-insert flange locknut includes a wider integral bearing surface.

These are different product geometries and should be selected according to the joint design.

DIN 985 and ISO Dimensional References

DIN 985 is associated with thin-pattern hexagonal prevailing-torque nuts with non-metallic inserts.

Other ISO standards cover different dimensional configurations.

The dimensional profile of this brass product must be confirmed from the approved drawing.

The material scope of a standard must also be verified.

A brass locknut manufactured to dimensions inspired by DIN 985 should not automatically be described as fully DIN 985 compliant.

Similarly, metric dimensional standards must not be applied directly to Unified inch-thread products.

Electrical Enclosures and Control Cabinets

Brass nylon-insert locknuts may be considered for selected mechanical fastening applications in electrical equipment.

Potential applications include:

• Electrical enclosure mounting brackets

• Control cabinet accessories

• Instrument mounting hardware

• Mechanical supports

• Terminal equipment brackets

• Equipment panel assemblies

The combination of conductive brass and prevailing-torque locking may be useful where both properties are required.

Electrical bonding and grounding requirements must be independently verified.

Electronics and PCB Equipment

Brass fastening components are frequently used in electronics and instrumentation.

Potential applications for suitably sized nylon-insert locknuts include:

• Circuit board support hardware

• Instrument mounting brackets

• Electronic enclosure accessories

• Equipment chassis assemblies

• Mechanical mounting points

Care must be taken to avoid excessive clamp load on circuit boards, insulating materials and delicate electronic components.

A brass nylon-insert locknut does not provide electrical insulation simply because it contains a nylon locking ring.

Instrumentation and Measurement Equipment

Instrumentation assemblies may require fasteners with controlled magnetic behavior and corrosion resistance.

Potential applications include:

• Instrument housings

• Measurement equipment brackets

• Sensor mounting accessories

• Laboratory equipment supports

• Precision equipment enclosures

For magnetically sensitive equipment, the complete assembly must be evaluated.

Industrial Machinery and Automation

Brass nylon-insert locknuts may be considered for selected light-duty and moderate-load mechanical assemblies where brass material properties are appropriate.

Potential applications include:

• Equipment accessories

• Automation fixtures

• Mechanical mounting brackets

• Instrument supports

• Serviceable machinery components

The required strength and thread engagement must be verified.

HVAC and Building Equipment

Brass nylon-insert locknuts may be evaluated for suitable HVAC equipment accessories and mechanical supports.

Potential applications include:

• Control equipment brackets

• Instrument mounting hardware

• Equipment enclosure accessories

• Selected mechanical assemblies

Temperature, moisture and chemical exposure must be considered.

Telecommunications and Data Center Equipment

Brass fastening components may be used in selected electronic and electrical infrastructure assemblies.

Potential applications include:

• Telecommunications equipment brackets

• Instrumentation hardware

• Control cabinet accessories

• Electronic equipment supports

• Mechanical chassis connections

Fastener selection should be based on actual mechanical and electrical requirements.

Power Electronics and Industrial Electrification

Power electronics equipment includes mechanical connections near electrical components, instrumentation and control hardware.

Brass nylon-insert locknuts may be considered for suitable mechanical assemblies where their material characteristics are advantageous.

For current-carrying joints, electrical connection performance must be separately designed and validated.

Medical and Laboratory Equipment

Brass nylon-insert locknuts may be evaluated for non-patient-contact equipment accessories, instrument supports and mechanical enclosures.

Any application involving medical-device safety, cleanliness or regulated performance requires the appropriate engineering and regulatory assessment.

No medical-device certification is implied.

Outdoor Electrical Equipment

Brass nylon-insert locknuts may be considered for selected outdoor electrical accessories and instrumentation.

Environmental evaluation should include:

• Humidity

• Condensation

• Chloride exposure

• Industrial chemicals

• Temperature

• Galvanic compatibility

• Maintenance requirements

Brass should not automatically be selected for aggressive marine or chemical environments without a suitable material assessment.

Temperature Limitations of Nylon Inserts

The locking insert may limit the operating temperature of the complete fastener.

The actual permissible temperature depends on the polymer grade, insert design and service conditions.

High temperatures can alter the mechanical properties of the insert and reduce prevailing-torque performance.

The complete fastener should be evaluated for the required operating temperature.

Installation and Reusability

Brass nylon-insert locknuts should be installed using a procedure appropriate to their material and prevailing-torque characteristics.

Important considerations include:

• Correct thread size and pitch

• Mating fastener material

• Thread condition

• Installation torque

• Required joint preload

• Lubrication specification

• Insert engagement

• Repeated installation

• Operating temperature

Brass is generally softer than many steel fastener materials.

Excessive installation torque or unsuitable thread engagement may damage the brass threads.

Reuse is permitted only where the applicable product specification and remaining locking performance allow it.

The number of permissible reuse cycles should not be assumed without testing.

Common Engineering Failure Risks

Thread Stripping

Possible causes include excessive tightening torque, inadequate thread engagement or incompatible mating fastener strength.

Loss of Prevailing Torque

Possible causes include insert wear, excessive temperature or repeated installation.

Galvanic Corrosion

Dissimilar-metal combinations may require evaluation where moisture or another electrolyte is present.

Stress-Corrosion Cracking

Some brass alloys can be susceptible under particular environmental and stress conditions.

Insufficient Clamp Load

Incorrect torque control or joint settlement may reduce the required preload.

Electrical Performance Problems

The presence of brass hardware does not guarantee a low-resistance electrical connection.

Electrical performance must be assessed for the complete assembly.

OEM Manufacturing Capabilities

Juxin Fasteners is an industrial fastener manufacturer specializing in standard and custom-engineered fastening components.

Our manufacturing capabilities include:

• Cold heading

• Cold forming

• CNC machining

• Product-specific secondary operations

• OEM/ODM made-to-drawing manufacturing

• Industrial batch production

Brass locknuts may require different manufacturing routes depending on alloy selection, geometry, dimensional tolerances and production volume.

The manufacturing process for each project is determined through engineering feasibility review.

Custom Brass Locknut Manufacturing

Juxin Fasteners supports customer-specific designs based on 2D drawings and 3D CAD models.

Custom requirements may include:

• Metric coarse or fine threads

• UNC and UNF threads

• Hexagon dimensions

• Nut height

• Brass alloy

• Insert material

• Insert retention geometry

• Surface finish

• Dimensional tolerances

• Prevailing-torque requirements

• Mechanical performance requirements

• Packaging and identification

Manufacturing feasibility must be reviewed for each custom specification.

Quality Inspection and Functional Validation

Depending on the customer drawing and applicable requirements, inspection may include:

• Brass material verification

• Internal thread gauging

• Hexagon width across flats

• Nut height

• Insert dimensions

• Insert retention

• Surface condition

• Dimensional tolerances

• Prevailing-torque testing

• Functional assembly testing

• Mechanical performance verification where specified

Testing methods and acceptance criteria must be defined for the actual product.

Frequently Asked Questions

What is a brass nylon-insert locknut?

It is a brass hex nut containing a retained non-metallic locking insert that creates prevailing torque against the mating bolt thread.

What is the American name for this product?

Brass Nylon-Insert Locknuts is a widely used American industrial product name.

Are brass nylon locknuts electrically conductive?

The brass body is conductive, but the complete joint's electrical performance must be verified where required.

Are brass nylon locknuts nonmagnetic?

Common brass alloys are generally nonmagnetic. Critical applications require material and assembly verification.

Are brass nylon locknuts corrosion-resistant?

Brass offers corrosion resistance in many environments, but suitability depends on alloy and exposure conditions.

Are brass nylon locknuts suitable for high temperatures?

Only within the qualified temperature limits of the complete fastener and its locking insert.

Can brass nylon locknuts be reused?

Reuse depends on the product specification and remaining prevailing-torque performance.

Are brass nylon locknuts compliant with DIN 985?

Compliance cannot be assumed from the product name. Nut dimensions, material scope and other requirements must be checked.

What metric sizes are identified?

M4, M5, M6, M8, M10 and M12.

What inch-thread sizes are identified?

#8-32, #10-32, 1/4-20, 3/8-16 and 1/2-13.

Can Juxin Fasteners manufacture custom UNC and UNF sizes?

Additional inch-thread designs can be evaluated according to engineering drawings and manufacturing feasibility.

Are metric and inch threads interchangeable?

No. The thread form, diameter, pitch and tolerance must match the mating fastener.

Can Juxin Fasteners manufacture brass nylon locknuts to OEM drawings?

Yes. We support OEM/ODM made-to-drawing manufacturing and industrial batch production.

Request a Quote — Brass Nylon-Insert Locknuts

Juxin Fasteners supports global OEM, Tier-1 and Tier-2 manufacturers requiring brass nylon-insert locknuts and custom industrial fastening components.

Our manufacturing capabilities combine cold heading, cold forming, CNC machining and product-specific secondary operations according to engineering requirements.

For an accurate quotation, please provide:

• 2D engineering drawing or 3D CAD model

• Customer part number

• Metric, UNC or UNF thread designation

• Thread diameter and pitch

• Brass alloy specification

• Nut height and hexagon dimensions

• Nylon insert specification

• Prevailing-torque requirements

• Mechanical performance requirements

• Surface finish

• Operating temperature

• Environmental conditions

• Dimensional tolerances

• Inspection and acceptance criteria

• Initial order quantity

• Estimated annual demand

• Packaging requirements

• Target delivery schedule

Our engineering team can review your specifications for manufacturing feasibility, custom production and long-term OEM supply.

Juxin Fasteners

Industrial Fastener Manufacturer | Brass Nylon-Insert Locknuts | OEM/ODM Fastener Manufacturing

Website: https://www.juxinfasteners.com/

Email: info@juxinfasteners.com

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.