Press-Fit Brass Threaded Inserts for Medical Equipment: Cold-Press Installation and OEM Engineering Guide

Press-Fit Brass Threaded Inserts for Medical Equipment: Precision Cold-Press Fastening Solutions for Injection-Molded Plastics

Medical equipment manufacturers use injection-molded plastic components in diagnostic instruments, laboratory equipment,

 electronic enclosures, monitoring systems and serviceable equipment housings.

These components often require reusable threaded connections for attaching covers, brackets, internal assemblies and mounting hardware.

Directly formed plastic threads may be suitable for certain applications. However, repeated screw installation,

 defined tightening loads or frequent maintenance can justify a metallic threaded interface.

Press-Fit Brass Threaded Inserts, also known as Press-In Brass Thread Insert Nuts or Cold-Press Brass Inserts for Plastics, 

provide reusable internal threads within appropriately designed plastic components.

Unlike heat-set or ultrasonic inserts, press-fit designs are installed mechanically, without deliberately heating the surrounding polymer.

Their performance depends on the insert's external retention geometry, plastic resin, molded hole dimensions, boss design, installation conditions and service loads.

For medical equipment OEMs, a successful design must also consider assembly cleanliness, 

documentation, traceability, production consistency and the finished device's intended use.

JUXIN FASTENERS supplies industrial threaded inserts and drawing-based fastening components for OEM plastic assemblies.

This guide explains how design engineers, manufacturing engineers, 

production managers and procurement teams can evaluate press-fit brass threaded inserts for selected medical equipment applications.

What Are Press-Fit Brass Threaded Inserts?

A press-fit brass threaded insert is a metallic fastener designed to be mechanically installed into a prepared hole in a plastic component.

The insert provides an internal screw thread and uses external retention features to engage the surrounding polymer.

Depending on the design, those features may include:

• Hexagonal external profiles

• Barbs or retention fins

• Straight knurls

• Diamond knurls

• Grooves

• Slotted compressible bodies

• Flanges

• Pilot features

The correct geometry depends on the polymer, hole dimensions and required mechanical performance.

Common Commercial Names

• Press-Fit Brass Threaded Inserts

• Press-In Brass Threaded Inserts

• Cold-Press Brass Inserts

• Brass Thread Insert Nuts

• Barbed Threaded Inserts for Plastics

• Hexagonal Press-In Inserts

• Solid Body Press-In Inserts

• Knurled Brass Threaded Inserts

• Threaded Inserts for Injection-Molded Plastics

These names describe related products but do not guarantee identical geometry or installation requirements.

Important Distinction

Press-fit installation is normally performed after the plastic component has been molded.

Molded-in installation places the insert inside the mold before the plastic is formed around it.

The two processes require different design and production considerations.

How Cold-Press Threaded Inserts Work

Cold-press installation uses controlled mechanical force to position the insert inside a prepared hole.

The insert's external features interact with the plastic to create retention.

Depending on the insert design, retention may involve:

• Local plastic displacement

• Interference fit

• Engagement of barbs or fins

• Resistance created by knurled surfaces

• Elastic compression of a slotted insert body

The internal thread remains available for a mating screw.

Basic Installation Sequence

1. Mold or prepare the plastic component with the specified hole geometry.

2. Verify the hole dimensions and local boss condition.

3. Align the insert with the hole.

4. Support the plastic component using suitable fixturing.

5. Apply controlled installation force.

6. Stop at the specified installation depth.

7. Inspect the installed insert.

8. Perform agreed mechanical verification where required.

Why Cold Installation Can Be Attractive

The process does not require a dedicated heat-setting or ultrasonic insertion cycle.

This may simplify equipment selection and reduce certain process steps.

However, the actual manufacturing advantage depends on component geometry, required force, cycle time, scrap rate and inspection requirements.

Cold Pressing Does Not Mean Zero Plastic Stress

Mechanical installation displaces or deforms the surrounding polymer.

If the interference is excessive, the plastic boss may crack or develop residual stress.

Cold-press inserts therefore require careful coordination between the insert supplier, plastic component designer and assembly process engineer.

Hexagonal and Barbed Press-Fit Insert Designs

Some press-fit inserts use hexagonal external geometry with barbed retention features.

Hexagonal Profile

A noncircular external profile can help resist rotation when properly engaged with the surrounding plastic.

Barbs and Retention Fins

These features may improve resistance to axial withdrawal by mechanically engaging the host material.

Solid Body Construction

A solid body can provide a rigid metallic thread interface.

However, the surrounding plastic must accommodate the installation stresses.

Slotted Insert Construction

Some press-in inserts use a slotted body that compresses during installation.

This can change the insertion-force and retention behavior compared with a solid-body design.

Why Insert Geometry Must Match the Plastic

An aggressive barb may provide useful retention in one polymer but cause cracking in another.

A design intended for a relatively rigid thermoset may not be suitable for a softer thermoplastic.

The actual insert drawing and application conditions must be evaluated together.

Industry Reference: Press-In Insert Design

PennEngineering's SI® press-in insert portfolio includes hexagonal barbed, slotted, flanged, straight-knurled and solid-body designs.

The manufacturer distinguishes these configurations according to installation behavior and retention features.

This illustrates why the term "press-fit threaded insert" should not be treated as one universal design.

Press-Fit Versus Heat-Set Versus Molded-In Inserts

The installation method should be selected according to the plastic material, production process and required performance.

When Press-Fit May Be Preferred

• The selected plastic supports mechanical insertion

• Thermal insertion is undesirable

• Post-mold installation is acceptable

• The insert geometry provides sufficient retention

• Assembly equipment can control insertion force and depth

When Heat-Set May Be Preferred

• A compatible thermoplastic can flow around retention features

• The application benefits from thermal insertion

• The boss design and equipment support a controlled process

When Molded-In May Be Preferred

• The insert can be positioned reliably during molding

• A separate post-mold operation is undesirable

• The molding process and insert design are compatible

No Method Is Universally Strongest

Retention performance must be demonstrated for the actual component.

Brass Material Selection for Press-Fit Inserts

Brass is widely used for threaded inserts because it can be machined into precise internal threads and external retention features.

Potential Advantages

• Good machinability

• Durable metallic threads

• Suitable dimensional precision

• Corrosion resistance in many environments

• Compatibility with various external geometries

Brass Alloy Selection

Brass alloys differ in composition, mechanical properties and lead content.

Some free-machining brass grades contain lead.

For medical equipment projects, the required alloy and material restrictions should be specified explicitly.

Why Brass Is Not Automatically Medical-Grade

A brass insert is not inherently:

• Biocompatible

• Sterile

• Lead-free

• Suitable for repeated sterilization

• Resistant to every disinfectant

• Approved for patient contact

These characteristics depend on the actual material, finished component and intended use.

Alternative Materials

Stainless steel or aluminum inserts may be considered where corrosion behavior, material restrictions, weight or mechanical requirements justify a different material.

Changing the insert material can also change installation and retention behavior.

The substitute must be validated.

Plastic Compatibility for Cold-Press Installation

The host polymer strongly influences press-fit performance.

Polycarbonate (PC)

May be used in selected medical equipment housings.

The design should consider local stress, cracking susceptibility and chemical exposure.

ABS and PC/ABS

May be suitable for certain equipment enclosures, depending on the resin grade and insert design.

Polypropylene (PP)

May be considered for selected applications, but its stiffness, creep behavior and retention performance require evaluation.

Polyamide (PA6 and PA66)

Moisture conditioning and resin grade can influence hole dimensions and mechanical behavior.

Glass-Filled Engineering Plastics

Reinforced materials may behave differently from unfilled resins.

Fiber content, fiber orientation and local molding conditions can influence cracking and retention.

Thermosetting Plastics

Some press-in insert designs are suitable for selected cured thermosets.

However, the material may have limited capacity to accommodate local deformation.

The insert geometry must be chosen accordingly.

Why Generic Material Names Are Insufficient

"Medical-grade plastic," "nylon" or "polycarbonate" does not define all relevant mechanical characteristics.

The OEM should identify the actual resin grade, fillers, conditioning and service environment.

Plastic Boss Design for Press-Fit Inserts

The boss is the local plastic structure that supports the insert.

It must resist both installation stresses and service loads.

Hole Diameter

The hole diameter must match the specific insert design.

An oversized hole may reduce retention.

An undersized hole may increase installation force and cracking risk.

Hole Shape

Some insert designs are intended for circular holes.

Others may use specific geometries.

The hole configuration must follow the selected insert's drawing.

Hole Depth

The hole must accommodate the insert and any required clearance.

The mating screw must not bottom out and create unwanted axial loading.

Boss Outside Diameter

Cold-press installation can create substantial local stresses.

Sufficient surrounding plastic is required to prevent cracking.

Boss Height

The boss must accommodate the insert length and support the intended load path.

Ribs and Reinforcement

Ribs may improve support when properly designed.

However, unsuitable geometry can create molding defects or stress concentrations.

Knit Lines and Molding Defects

Weak knit lines, voids or inconsistent local material conditions can reduce boss strength.

Why Cold-Press Inserts May Need More Surrounding Plastic

SPIROL's design guidance notes that cold-pressed inserts may require larger bosses or wall thicknesses because installation induces mechanical stresses.

This is particularly important when converting a design from heat-set insertion to press-fit installation.

Do Not Reuse Hole Dimensions from Another Insert

Two inserts with the same M8 internal thread can have different outside diameters, retention profiles and hole requirements.

The internal thread alone does not define the mounting hole.

Engineering Example: M8 Press-Fit Brass Insert

An OEM may request an M8 brass threaded insert for a medical equipment housing.

Before selecting the part, the engineering team should confirm:

• M8 thread pitch

• Insert outside diameter

• Insert length

• External hexagonal or barbed geometry

• Brass alloy

• Hole diameter and tolerance

• Boss outside diameter

• Boss height

• Plastic resin grade

• Installation force range established by testing

• Required torque-out resistance

• Required pull-out resistance

• Mating screw length

• Operating environment

Why M8 Is Not a Complete Specification

M8 identifies the nominal internal thread diameter.

It does not determine the insert's external dimensions, installation method or retention performance.

Installation Force: What Should Be Specified?

The original engineering challenge is not simply to achieve a high pressing force.

The goal is to install the insert consistently without damaging the plastic.

Force Too Low

Possible outcomes:

• Incomplete insertion

• Poor engagement

• Incorrect seating

• Reduced retention

Force Too High

Possible outcomes:

• Boss cracking

• Local plastic deformation

• Insert damage

• Tooling damage

• Excessive residual stress

Force-Displacement Monitoring

A controlled press may record the relationship between applied force and insertion travel.

This can help identify:

• Unexpected resistance

• Incorrect hole dimensions

• Misalignment

• Incomplete seating

• Abnormal installation conditions

Why There Is No Universal PC or PP Pressing Pressure

A single pressure value cannot be applied to every insert and polymer.

Installation behavior depends on the actual contact geometry, insert design, resin, hole dimensions and equipment.

Press force should be established through production-representative trials.

Installation Depth and Alignment

The insert must be installed to the depth required by the joint design.

Too Shallow

May interfere with the mating component or reduce effective seating.

Too Deep

May damage the boss, reduce useful thread access or create assembly problems.

Misaligned

May cause uneven loading, plastic damage or difficulty engaging the screw.

Practical Controls

• Defined drawing datums

• Correct hole position

• Suitable component support

• Guided insertion tooling

• Controlled press travel

• Inspection of installed position

No Universal 60%–70% Embedment Rule

Embedding depth should follow the insert geometry and approved assembly drawing.

It cannot be defined as a fixed percentage of plastic wall thickness for all designs.

Pull-Out Strength and Torque-Out Resistance

These are two different retention requirements.

Pull-Out Resistance

Measures resistance to axial withdrawal from the plastic.

Torque-Out Resistance

Measures resistance to rotation within the plastic.

Thread Strength

Concerns the internal metallic thread and mating fastener.

Boss Strength

Concerns the surrounding plastic structure.

Why One Test Is Not Enough

An insert may resist axial pull-out but rotate during screw tightening.

Another insert may resist rotation but crack the boss during installation.

The qualification plan should reflect the actual service loads.

How to Validate Retention

Use the specified insert installed in production-representative plastic components.

Record relevant conditions, including:

• Resin grade

• Hole dimensions

• Insert dimensions

• Installation process

• Conditioning

• Test method

• Failure mode

Test results from a different resin or insert geometry should not be assumed to apply.

Preventing Jack-Out and Screw Bottoming

Jack-out is an important failure mode in plastic insert assemblies.

It can occur when the mating-part geometry or screw engagement creates an unintended load that displaces the insert.

Mating-Part Clearance Hole

The clearance hole must allow the screw to pass while providing the intended bearing and load path.

Screw Length

The screw must not bottom out in a blind hole or otherwise create damaging axial force.

Insert Seating

The installed insert must be positioned correctly relative to the mating component.

Headed Insert Considerations

A headed or flanged insert may be appropriate where the joint requires additional bearing area.

Why the Load Path Matters

The insert should carry the intended load rather than allowing the plastic to be compressed or pried in an uncontrolled manner.

Plastic Creep and Clamp Load

Plastic materials may deform under sustained loading.

This can affect joint preload over time.

A metallic internal thread does not eliminate creep in the surrounding plastic.

Compression Limiters

Where appropriate, a separate compression limiter can help manage compressive loads.

The threaded insert provides the thread.

The compression limiter provides a controlled compressive load path.

The two components should be designed together where the application requires both.

Medical Equipment Applications

Press-fit brass threaded inserts may be considered for selected non-patient-contact components in medical equipment.

Diagnostic Equipment

• Analyzer housings

• Instrument covers

• Serviceable electronics enclosures

• Mounting brackets

Laboratory Equipment

• Equipment panels

• Instrument housings

• Control modules

• Removable covers

Patient-Monitoring Equipment

• Selected electronic enclosures

• Auxiliary plastic housings

• Serviceable mounting components

Medical Imaging Equipment

• Auxiliary covers

• Electronic module housings

• Noncritical plastic mounting components

Portable Medical Equipment

• Serviceable plastic housings

• Internal equipment brackets

• Selected accessory enclosures

Important Application Boundary

These examples do not establish suitability for patient-contacting components, sterile fluid pathways, implants or safety-critical medical connections.

Such applications require separate technical and regulatory evaluation.

Cleaning and Disinfection Compatibility

Medical equipment may be exposed to cleaning agents and disinfectants.

The metal insert and plastic component must be evaluated together.

Potential Risks

• Plastic environmental stress cracking

• Brass discoloration

• Corrosion

• Residue accumulation

• Changes in retention performance

• Damage from repeated exposure

Questions for the OEM

• Which cleaning chemicals are used?

• At what concentration?

• What is the exposure time?

• What temperature is expected?

• How frequently will cleaning occur?

• Is sterilization required?

• Is the insert exposed or enclosed?

Cold Pressing Does Not Guarantee Cleanliness

A process without heating may avoid some thermal effects, but it can still generate particles or plastic debris.

Cleanliness must be controlled and verified according to the OEM's requirements.

Sterilization Compatibility

Not all medical equipment components require sterilization.

Where sterilization is required, the actual process must be specified.

Potential methods may include steam, ethylene oxide or radiation, depending on the finished device.

The material combination and joint performance must be evaluated after the relevant processing conditions.

A Brass Insert Is Not Automatically Sterilization-Compatible

Compatibility cannot be established solely from the material name.

Automated Cold-Press Assembly

Press-fit threaded inserts may be installed using manual, semi-automatic or automated equipment.

Possible Equipment Features

• Controlled pressing force

• Defined installation travel

• Automatic feeding

• Insert orientation control

• Position monitoring

• Force-displacement recording

• Part-presence detection

• Reject handling

The available functions depend on the actual production equipment.

Production Manager Considerations

• Cycle time

• Feeding reliability

• Equipment uptime

• Tooling maintenance

• Changeover requirements

• Scrap rate

• Rework

• Inspection time

• Cost per accepted assembly

Why Faster Installation Is Not Always Cheaper

A shorter press cycle may still result in higher total cost if it creates cracking, misalignment or additional inspection requirements.

The process should be evaluated by accepted output, not insertion speed alone.

Pilot Production and Process Qualification

Before full production, evaluate the insert using representative components and intended equipment.

A practical qualification plan may include:

• Dimensional inspection

• Installation trials

• Force-displacement review

• Installed-depth verification

• Pull-out testing

• Torque-out testing

• Mating screw assembly

• Environmental exposure where required

• Review of failure modes

Why Prototype Success Is Not Enough

A prototype may be produced under different molding, handling or installation conditions from mass production.

The approved process must account for normal production variation.

Common Press-Fit Insert Failure Modes

Plastic Boss Cracking

Possible causes:

• Excessive interference

• Insufficient boss material

• Brittle resin behavior

• Weak knit lines

• Incorrect insertion alignment

Insert Rotation

Possible causes:

• Insufficient engagement

• Oversized hole

• Incorrect insert geometry

• Excessive tightening torque

Insert Pull-Out

Possible causes:

• Inadequate barb engagement

• Incorrect hole dimensions

• Insufficient boss strength

• Excessive axial loading

Incorrect Installation Depth

Possible causes:

• Poor travel control

• Inconsistent hole depth

• Tooling wear

• Incorrect setup

Insert Tilting

Possible causes:

• Poor alignment

• Inadequate component support

• Incorrect feeding orientation

• Hole-position variation

Thread Damage

Possible causes:

• Incorrect mating screw

• Cross-threading

• Excessive assembly torque

• Damaged insert thread

Contamination

Possible causes:

• Machining residues

• Burrs

• Plastic debris

• Handling or packaging contamination

Loss of Clamp Load

Possible causes:

• Plastic creep

• Stress relaxation

• Incorrect load path

• Unsuitable joint geometry

Root-Cause Analysis

A useful investigation separates the insert, plastic component and installation process.

Insert Factors

• Material grade

• External geometry

• Thread accuracy

• Length

• Outside diameter

• Burrs

• Surface condition

Plastic Factors

• Resin grade

• Filler content

• Hole dimensions

• Boss geometry

• Molding defects

• Moisture conditioning

Process Factors

• Press force

• Installation travel

• Tool alignment

• Fixturing

• Equipment condition

• Assembly torque

Corrective actions should be verified through appropriate testing.

Quality Control for Press-Fit Brass Threaded Inserts

Quality control should cover both the insert and the installed assembly.

Incoming Insert Inspection

Depending on the drawing:

• Brass alloy identification

• Internal thread size and pitch

• Thread tolerance

• Overall length

• Outside diameter

• Hexagonal geometry

• Barb or knurl dimensions

• Surface finish

• Burrs and visual defects

Plastic Component Inspection

• Hole diameter

• Hole depth

• Hole position

• Boss dimensions

• Visible molding defects

Installation Process Control

• Equipment setup

• Press force

• Insertion travel

• Alignment

• Fixturing

• Process records

Final Assembly Inspection

• Insert presence

• Installation depth

• Position

• Visible plastic damage

• Thread accessibility

• Agreed mechanical testing

Documentation

Inspection records, material information and lot identification should be provided according to the agreed purchasing and quality requirements.

Medical Device Quality and Regulatory Considerations

Medical equipment OEMs may require supplier controls that go beyond ordinary industrial purchasing.

However, medical device quality requirements must be interpreted according to the finished device and the supplier's actual role.

ISO 13485:2016

Defines quality management system requirements for medical devices and related regulatory purposes.

FDA Quality Management System Regulation

The FDA QMSR became effective on February 2, 2026, incorporating ISO 13485:2016 into the relevant U.S. medical device quality system framework.

ISO 14971:2019

Provides a framework for medical device risk management.

ISO 10993-1:2025

Addresses biological safety evaluation within the medical device risk management process where relevant contact and exposure conditions apply.

Important Supplier Compliance Distinction

Supplying a brass threaded insert for a medical equipment housing does not automatically establish that the insert is a finished medical device.

Nor does it establish FDA approval, ISO 13485 certification, biocompatibility or sterilization validation.

Any required certification, documentation or testing must be confirmed for the specific project.

International Thread Standards

The internal thread should be specified according to the applicable thread system.

ISO 261

General-purpose ISO metric screw thread series.

ISO 965 Series

ISO metric screw thread tolerances.

ASME B1.1

Unified inch screw threads, including UNC and UNF.

Metric Thread Examples

• M3 × 0.5

• M4 × 0.7

• M5 × 0.8

• M6 × 1.0

• M8 × 1.25

Unified Inch Thread Examples

• 4-40 UNC

• 6-32 UNC

• 8-32 UNC

• 10-24 UNC

• 10-32 UNF

• 1/4-20 UNC

These are thread designation examples, not confirmation that every size is available in every press-fit insert design.

Metric, UNC, UNF, BSW and BSF are not directly interchangeable.

Custom Press-Fit Brass Threaded Inserts for OEMs

A standard catalog insert may not match every medical equipment housing.

Custom drawing-based requirements may include:

• Internal thread size and pitch

• Overall length

• Outside diameter

• Hexagonal body dimensions

• Barb or retention-fin geometry

• Knurl configuration

• Head or flange dimensions

• Pilot features

• Blind or through-thread configuration

• Brass alloy

• Surface treatment

• Critical tolerances

• Automatic feeding requirements

Why Customization May Be Necessary

A compact diagnostic instrument may have limited boss space.

A laboratory enclosure may require repeated service access.

An automated assembly line may need a specific insert orientation.

A medical equipment manufacturer may require defined material documentation or packaging controls.

The design should be based on the actual component and assembly process.

Supplier Development and Second-Source Qualification

Procurement and supply chain teams may evaluate alternative suppliers to improve sourcing flexibility or manage cost.

However, two press-fit inserts with the same internal thread are not automatically interchangeable.

Critical Comparison Points

• Internal thread

• Outside diameter

• Overall length

• Hexagonal or knurled geometry

• Barb configuration

• Brass alloy

• Surface treatment

• Hole requirements

• Installation force behavior

• Pull-out resistance

• Torque-out resistance

Second-Source Qualification

1. Review the approved drawing.

2. Identify critical dimensions and materials.

3. Compare the proposed alternative.

4. Install samples into representative molded components.

5. Evaluate the required mechanical performance.

6. Confirm compatibility with production equipment.

7. Obtain customer approval where required.

Total Installed Cost

The total cost includes more than the insert's unit price.

It may include:

• Insert purchasing

• Plastic molding

• Installation equipment

• Cycle time

• Tooling maintenance

• Scrap

• Rework

• Inspection

• Supplier qualification

• Packaging and logistics

A lower unit price may not reduce the cost of the accepted assembly.

JUXIN FASTENERS Press-Fit Brass Insert Solutions

JUXIN FASTENERS supplies industrial threaded inserts and custom fastening components for plastic assemblies.

Relevant sourcing categories include:

• Press-Fit Brass Threaded Inserts

• Cold-Press Thread Insert Nuts

• Barbed Threaded Inserts

• Hexagonal Press-In Inserts

• Knurled Brass Threaded Inserts

• Custom Brass Threaded Bushings

• Heat-Set Threaded Inserts

• Ultrasonic Threaded Inserts

• Molded-In Threaded Inserts

Specific geometries, materials, dimensions, inspection requirements and commercial terms require project-level confirmation.

Related JUXIN FASTENERS Products and Technical Resources

Custom Threaded Inserts for OEM Plastic Components

How to Choose Threaded Inserts for Injection Molded Parts

Threaded Inserts for Glass-Filled Plastics and Composites

Threaded Inserts for ABS, Nylon, PC, PBT and PEEK

These resources support material selection, custom geometry evaluation and injection-molded component design.

Frequently Asked Questions About Press-Fit Brass Threaded Inserts

What is a press-fit brass threaded insert?

It is a brass component mechanically installed into a prepared plastic hole to provide a reusable internal thread.

Is press-fit the same as molded-in?

No. Press-fit inserts are generally installed after molding, while molded-in inserts are positioned before plastic forming.

Do press-fit inserts require heating?

Conventional cold-press installation does not deliberately heat the insert or surrounding plastic.

Can press-fit inserts crack plastic?

Yes. Excessive interference or inadequate boss design can cause cracking.

Are hexagonal press-fit inserts better than knurled inserts?

Not universally. Performance depends on geometry, polymer and loading.

Can press-fit brass inserts be used in medical equipment?

They may be suitable for selected applications after appropriate engineering and quality evaluation.

Are brass inserts automatically medical-grade?

No. Material and application suitability must be established.

What is the best hole diameter for an M8 press-fit insert?

There is no universal hole diameter. It depends on the selected insert's outside geometry and the plastic material.

What pressing force should be used for PC or PP?

The required force must be established for the actual insert, polymer, hole and equipment.

What is the difference between pull-out and torque-out resistance?

Pull-out resistance concerns axial withdrawal, while torque-out resistance concerns rotation.

Does cold pressing eliminate thermal damage?

It avoids deliberately applying heat during installation but can still create mechanical stress and deformation.

Can press-fit inserts withstand sterilization?

Compatibility must be evaluated for the actual material combination and processing conditions.

Can an insert with the same M8 thread replace another insert?

Not automatically. External geometry, material, hole requirements and retention behavior must also match.

Can JUXIN FASTENERS evaluate custom press-fit inserts?

Yes. Drawing-based requirements may be submitted for technical and commercial evaluation.

OEM RFQ — Press-Fit Brass Threaded Inserts for Medical Equipment

JUXIN FASTENERS welcomes inquiries from medical equipment manufacturers, plastic injection molding companies, design engineers, 

manufacturing engineers, production managers, procurement specialists, supplier development teams and global supply chain managers.

For technical evaluation and quotation, please provide the following information where applicable.

Insert Specifications

• 2D engineering drawing

• 3D CAD model where available

• Internal thread size and pitch

• Metric or Unified inch designation

• Overall length

• Outside diameter

• Hexagonal, barbed or knurled geometry

• Head or flange configuration

• Brass alloy

• Surface treatment

• Critical tolerances

Plastic Component Information

• Resin grade

• Filler content

• Molded hole diameter

• Hole tolerance

• Hole depth

• Boss diameter

• Boss height

• Wall thickness

• Mating component geometry

Installation Requirements

• Cold-press installation method

• Installation equipment

• Required seating depth

• Force or travel monitoring requirements

• Automatic feeding requirements

• Production cycle considerations

Mechanical Requirements

• Pull-out resistance

• Torque-out resistance

• Assembly tightening torque

• Screw engagement

• Repeated assembly requirements

• Vibration or fatigue exposure

• Temperature and humidity conditions

Medical Equipment Quality Requirements

• Intended application

• Cleaning or disinfection exposure

• Sterilization requirements, if applicable

• Material documentation

• Cleanliness requirements

• Traceability

• Inspection and testing

• Packaging requirements

• Supplier change-control requirements

Commercial Requirements

• Sample quantity

• Initial order quantity

• Estimated annual demand

• MOQ expectations

• Delivery schedule

• Required documentation

Company: Juxin Fasteners

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

Email: info@juxinfasteners.com

Send your engineering drawings and application requirements to JUXIN FASTENERS for evaluation of press-fit brass threaded inserts,

 barbed insert nuts, custom threaded bushings and OEM plastic fastening solutions.

The most reliable press-fit threaded connection begins with the correct insert geometry, compatible plastic boss design, 

controlled installation process and verified assembly requirements.