16ER & 16IR Carbide CNC Threading Inserts

Precision Threading Inserts for External & Internal CNC Thread Turning

Zhuzhou Century Tool is a professional manufacturer of 16ER and 16IR carbide CNC threading inserts, providing high-performance threading solutions for precision machining applications worldwide. Designed for both external and internal thread cutting, our carbide threading inserts combine premium tungsten carbide substrates with advanced PVD and CVD coating technologies to deliver excellent wear resistance, superior thread accuracy, and extended tool life.

Our threading inserts are compatible with most ISO-standard threading toolholders and are widely used in CNC lathes for machining carbon steel, stainless steel, alloy steel, cast iron, and other engineering materials. Whether you are producing standard metric threads, unified threads, BSP threads, or custom thread profiles, Zhuzhou Century Tool provides reliable threading inserts that ensure consistent performance in both continuous and interrupted cutting operations.

With years of experience in carbide tooling manufacturing, we also provide OEM and custom threading insert solutions for cutting tool distributors, industrial suppliers, and machine tool manufacturers around the world.

Why Choose Our 16ER & 16IR Threading Inserts?

Thread turning requires exceptional dimensional accuracy and edge stability. Even a slight variation in insert geometry can affect thread quality, tool life, and production efficiency. Our inserts are engineered to maintain consistent cutting performance throughout long production runs.

Key Features

• Premium ultra-fine grain tungsten carbide substrate

• High wear resistance for extended service life

• Precision-ground cutting edges for accurate thread profiles

• Excellent chip control during threading operations

• Stable cutting performance under high-speed machining

• Available with PVD and CVD coatings

• Compatible with ISO standard threading toolholders

• Suitable for dry and wet machining

• OEM laser marking and private-label packaging available

• Consistent quality from batch to batch

Each insert is manufactured under strict quality control procedures to ensure dimensional consistency and reliable machining performance.

Product Specifications

Understanding 16ER & 16IR Inserts

The "16" indicates the insert size, while "ER" and "IR" refer to the threading direction and application.

16ER

16ER inserts are designed for external thread turning. They are commonly used for machining shafts, bolts, pipe threads, hydraulic fittings, and other external threaded components.

Typical applications include:

• Metric threads

• Unified threads

• BSP threads

• NPT pipe threads

• Trapezoidal threads

16IR

16IR inserts are designed for internal thread turning. They provide excellent chip evacuation and thread accuracy when machining internal bores and threaded holes.

Typical applications include:

• Internal metric threads

• Pipe fittings

• Hydraulic components

• Valve bodies

• Precision mechanical parts

Both insert types are manufactured according to ISO standards and fit most international threading toolholders.

Available Models

We supply a comprehensive range of threading insert geometries.

ISO Metric

• 16ER 0.50 ISO

• 16ER 0.75 ISO

• 16ER 1.00 ISO

• 16ER 1.25 ISO

• 16ER 1.50 ISO

• 16ER 1.75 ISO

• 16ER 2.00 ISO

• 16ER 2.50 ISO

• 16ER 3.00 ISO

• 16IR 0.50 ISO

• 16IR 0.75 ISO

• 16IR 1.00 ISO

• 16IR 1.25 ISO

• 16IR 1.50 ISO

• 16IR 1.75 ISO

• 16IR 2.00 ISO

• 16IR 2.50 ISO

• 16IR 3.00 ISO

American Unified Threads

• 16ER AG60

• 16IR AG60

• 16ER A55

• 16IR A55

Pipe Thread Series

• 16ER NPT

• 16IR NPT

• 16ER BSPT

• 16IR BSPT

Trapezoidal Thread Series

• 16ER TR

• 16IR TR

ACME Thread Series

• 16ER ACME

• 16IR ACME

Custom thread profiles are available upon request.

Advantages of Precision Ground Threading Inserts

Compared with molded threading inserts, precision-ground inserts offer superior dimensional accuracy and surface finish.

Benefits include:

• More accurate thread profiles

• Lower cutting forces

• Improved chip evacuation

• Better repeatability

• Longer tool life

• Higher productivity

• Reduced machine downtime

• Lower cost per threaded component

These advantages make precision-ground carbide threading inserts the preferred choice for high-volume production and precision machining industries.

Typical Applications

Our 16ER and 16IR carbide threading inserts are widely used for manufacturing:

• Bolts and fasteners

• Hydraulic fittings

• Pipe connectors

• Automotive shafts

• Aerospace components

• Oil & gas valves

• Medical equipment

• General mechanical parts

• Precision engineering components

• Industrial machinery

Whether producing standard or custom thread forms, our inserts deliver stable machining performance, excellent surface finish, and consistent dimensional accuracy across a wide range of production environments.

Carbide Grades & Coating Technologies

Selecting the correct carbide grade and coating is one of the most important factors in achieving stable threading performance, longer tool life, and lower machining costs. Different workpiece materials generate different cutting temperatures, chip loads, and wear mechanisms. Zhuzhou Century Tool offers multiple carbide grades and coating options to match a wide range of threading applications.

Our engineers can recommend the most suitable insert grade based on your workpiece material, CNC machine, cutting speed, coolant conditions, and production requirements.

Recommended Carbide Grades

Customized carbide grades are available for specific applications.

Advanced Coating Technologies

The coating protects the carbide substrate from heat, friction, and abrasion while improving chip flow and extending insert life.

TiN Coating

Titanium Nitride (TiN) is a general-purpose coating suitable for light machining operations.

Advantages:

• Low friction coefficient

• Good wear resistance

• Bright gold surface for easy wear monitoring

• Suitable for low-speed threading

Recommended for:

• Carbon steel

• Low alloy steel

• General machining

TiCN Coating

Titanium Carbonitride provides higher hardness than TiN and offers excellent abrasion resistance.

Advantages:

• Higher hardness

• Improved flank wear resistance

• Better performance in medium-speed cutting

Recommended for:

• Medium carbon steel

• Structural steel

• Alloy steel

TiAlN Coating

TiAlN is one of the most widely used PVD coatings for modern CNC machining.

Advantages:

• Excellent oxidation resistance

• High hot hardness

• Superior edge protection

• Outstanding performance under dry machining

Recommended for:

• Stainless steel

• Heat-resistant alloys

• High-speed threading

AlCrN Coating

Aluminum Chromium Nitride is designed for demanding machining environments where cutting temperatures are extremely high.

Advantages:

• Excellent thermal stability

• Reduced crater wear

• Longer tool life

• Suitable for difficult-to-machine materials

Recommended for:

• Hardened steel

• Alloy steel

• Tool steel

Multi-Layer CVD Coating

Our CVD-coated threading inserts combine multiple functional layers to achieve excellent wear resistance during continuous production.

Advantages:

• Thick coating layer

• High compressive strength

• Excellent resistance to abrasive wear

• Long tool life in large production runs

Recommended for:

• Carbon steel

• Cast iron

• Automated production lines

Workpiece Materials

Different materials require different insert grades, coatings, and cutting parameters. Choosing the correct combination improves thread quality while reducing insert consumption.

Carbon Steel

Typical materials include:

• AISI 1018

• AISI 1045

• C45

• S45C

Recommended Grade:

CT201

Recommended Coating:

Multi-layer CVD

Benefits:

• Stable cutting performance

• Excellent thread profile accuracy

• Long insert life

Stainless Steel

Typical materials include:

• 304

• 316

• 321

• Duplex Stainless Steel

Recommended Grade:

CT101

Recommended Coating:

TiAlN or AlCrN

Benefits:

• Reduced built-up edge

• Excellent edge toughness

• Improved surface finish

Alloy Steel

Typical materials include:

• 4140

• 4340

• SCM440

• 42CrMo

Recommended Grade:

CT301

Recommended Coating:

AlCrN

Benefits:

• Excellent wear resistance

• Stable cutting under heavy loads

• Consistent thread accuracy

Cast Iron

Typical materials include:

• Gray Iron

• Ductile Iron

• High-strength Cast Iron

Recommended Grade:

CT401

Recommended Coating:

Multi-layer CVD

Benefits:

• High abrasion resistance

• Stable machining

• Excellent dimensional consistency

Aluminum & Non-Ferrous Metals

Typical materials include:

• Aluminum Alloys

• Brass

• Copper

• Bronze

Recommended Grade:

CT501

Recommended Surface:

Polished or Uncoated

Benefits:

• Extremely sharp cutting edge

• Low cutting force

• Excellent surface finish

Recommended Cutting Conditions

The following parameters are for reference only. Actual cutting data should be adjusted according to machine rigidity, coolant conditions, workpiece hardness, and thread profile.

For high-volume production, our application engineers can provide optimized cutting parameters based on your CNC machine model and workpiece material.

Partial Profile vs Full Profile Threading Inserts

Choosing the correct insert profile is essential for thread quality and production efficiency.

For job shops and general machining, partial-profile inserts provide greater flexibility. For dedicated mass production, full-profile inserts offer superior thread consistency and productivity.

External vs Internal Threading Inserts

Although 16ER and 16IR inserts share similar carbide grades and coatings, their geometries are optimized for different machining operations.

16ER Inserts

• Designed for external thread turning

• Suitable for shafts, bolts, pipe fittings, and threaded rods

• Excellent chip evacuation in open machining environments

16IR Inserts

• Designed for internal thread turning

• Optimized for threading inside bores

• Improved chip control in confined cutting conditions

• High dimensional accuracy for precision internal threads

Selecting the correct insert geometry helps reduce vibration, improve chip evacuation, and achieve consistent thread quality.

Manufacturing Process

Every threading insert begins with high-quality tungsten carbide powder and passes through a precisely controlled manufacturing process. At Zhuzhou Century Tool, every production stage is carefully monitored to ensure consistent dimensions, edge quality, and cutting performance.

Step 1 – Raw Material Selection

The performance of a threading insert starts with the carbide substrate.

We use carefully selected tungsten carbide powder combined with cobalt binders to achieve the ideal balance between hardness, toughness, and wear resistance. Different carbide grades are formulated for different machining applications, allowing our inserts to perform reliably in steel, stainless steel, cast iron, alloy steel, and non-ferrous materials.

Step 2 – Powder Mixing

Carbide powder is blended with binders under controlled conditions to ensure homogeneous particle distribution.

Uniform powder composition is essential for:

• Consistent hardness

• Stable grain structure

• Improved fracture resistance

• Reliable batch-to-batch quality

Step 3 – Precision Pressing

Using high-precision molds and automatic presses, carbide powder is compacted into insert blanks.

Our pressing process ensures:

• Uniform density

• Accurate insert geometry

• Reduced internal stress

• Excellent dimensional consistency

Step 4 – Vacuum Sintering

Pressed inserts are sintered at high temperatures in a vacuum furnace.

During sintering, carbide particles are metallurgically bonded to create a dense and extremely hard cutting material.

The result is:

• High mechanical strength

• Excellent wear resistance

• Stable microstructure

• Long service life

Step 5 – Precision Grinding

After sintering, each insert undergoes precision grinding to achieve accurate dimensions and cutting-edge geometry.

Grinding operations include:

• Edge preparation

• Profile grinding

• Corner radius control

• Surface finishing

Precision grinding directly influences thread accuracy and insert stability during machining.

Step 6 – Advanced Coating

Depending on the application, inserts receive either PVD or CVD coatings.

These coatings improve:

• Wear resistance

• Heat resistance

• Oxidation resistance

• Chip flow

• Tool life

Multiple coating options are available to match different workpiece materials and cutting conditions.

Step 7 – Final Inspection

Before shipment, every production batch is inspected according to strict quality standards.

Only qualified inserts proceed to packaging and delivery.

Quality Control

Thread accuracy depends on insert accuracy.

For this reason, quality control is integrated into every stage of production rather than performed only at the end of the manufacturing process.

Our quality management procedures include:

Incoming Material Inspection

Raw carbide powders are inspected for:

• Chemical composition

• Grain size

• Purity

• Moisture content

Process Inspection

During production, technicians monitor:

• Insert dimensions

• Edge preparation

• Pressing density

• Sintering parameters

• Grinding accuracy

This helps prevent deviations before they affect final product quality.

Final Product Inspection

Finished threading inserts undergo comprehensive inspection, including:

• Dimensional measurement

• Surface quality inspection

• Coating appearance

• Thread profile verification

• Edge integrity

• Hardness testing

• Random cutting performance tests

Only products meeting our internal quality standards are approved for shipment.

OEM & Custom Manufacturing

Every machining application is unique. Standard inserts may not always deliver the best performance for specialized production environments.

Zhuzhou Century Tool provides flexible OEM and custom manufacturing services for cutting tool brands, distributors, machine builders, and industrial suppliers.

Our customization capabilities include:

• Custom insert geometries

• Special thread profiles

• Customized carbide grades

• PVD or CVD coating selection

• Optimized chip breaker design

• Edge honing and polishing

• Laser logo engraving

• Private-label packaging

• Customized labeling and barcodes

Whether you provide technical drawings, 3D models, or physical samples, our engineering team can develop inserts that meet your exact machining requirements.

Factory Advantages

Located in Zhuzhou—the center of China's tungsten carbide industry—our manufacturing facility benefits from a mature industrial supply chain, experienced technical personnel, and advanced production equipment.

Our advantages include:

• Experienced engineering team

• Stable raw material supply

• Modern manufacturing equipment

• Strict quality management

• Flexible production scheduling

• Competitive factory pricing

• Efficient export logistics

• Responsive technical support

These strengths enable us to supply both standard ISO inserts and customized OEM solutions with consistent quality and reliable lead times.

Packaging & Global Delivery

To ensure products arrive in perfect condition, every threading insert is carefully packed using protective packaging suitable for international transportation.

Packaging options include:

• Standard plastic insert boxes

• OEM branded packaging

• Customized labels

• Barcode labels

• Bulk industrial packaging

• Export cartons

Products are shipped worldwide by:

• Express courier

• Air freight

• Sea freight

• Railway transportation (where applicable)

Our logistics team works closely with international freight partners to ensure efficient and reliable delivery.

Why Choose Zhuzhou Century Tool?

Selecting a threading insert supplier is about more than price. It is about consistent quality, dependable delivery, and professional technical support.

Customers choose Zhuzhou Century Tool because we offer:

Factory-Direct Manufacturing

As a manufacturer, we control production from carbide powder selection to final inspection, ensuring stable quality and competitive pricing.

Professional Engineering Support

Our engineers help customers select the most suitable insert grade, coating, and geometry based on machining conditions rather than simply recommending standard products.

Reliable Batch Consistency

Strict manufacturing control ensures every production batch delivers consistent cutting performance, reducing insert variation and improving process stability.

Flexible OEM Solutions

From customized grades and coatings to laser marking and branded packaging, we support customers building their own cutting tool brands.

Fast Response

Technical inquiries and quotations are handled promptly by our experienced sales and engineering teams.

Global Supply Experience

Our carbide cutting tools are supplied to distributors, machine shops, and industrial manufacturers in more than 20 countries, supporting applications across automotive, aerospace, energy, mold & die, and general engineering industries.

Our Commitment

At Zhuzhou Century Tool, we believe that every threading insert should contribute to greater machining efficiency, longer tool life, and lower production costs.

Instead of simply supplying cutting tools, we work closely with our customers to develop practical machining solutions that improve productivity and support long-term manufacturing success.

Whether you require standard ISO threading inserts or customized OEM solutions, our team is committed to delivering reliable products backed by professional technical support and responsive customer service.