Ultimate Guide to Delrin Plastic: Properties, Applications, and CNC Machining Services

Are you wondering what Delrin plastic is and why it nowadays is the material of choice when it comes to precision parts in industries? You’re not alone. This thermoplastic has been engineered and has transformed the production of products, both in the automotive and the medical sector.

It is time to learn all about Delrin plastic, its peculiarities, other materials comparison, and why the Delrin plastic machining service providers depend on the material in high-precision projects. 

Understand The Basics of Derlin Plastic

Delrin is a high-performance acetal homopolymer manufactured by DuPont. Many people ask, “is Delrin a plastic?” Yes, it’s an engineering-grade thermoplastic known for its exceptional mechanical properties.

Key Characteristics of Delrin

Delrin stands out from standard plastics because of these features:

• Superior dimensional stability – maintains shape under stress
• Faible absorption d'humidité – less than 0.25% water uptake
• Excellente usinabilité – ideal for Service CNC applications
• High tensile strength – 10,000 psi (69 MPa)
• Natural lubricity – self-lubricating properties reduce friction

The material was introduced by DuPont in 1960 and has since become an industry standard. Its chemical name is polyoxymethylene (POM), but “Delrin” is the branded trade name that most engineers recognize.

Delrin Plastic Sheet: Types, Grades, and Specifications

When you’re looking at Delrin plastic sheet options, understanding the different grades helps you select the right material.

Common Delrin Grades

Delrin 150 SA (Black)

• Improved wear resistance
• Contains 15% PTFE lubricant
• Best for high-friction applications
• Used in gears, bearings, and wear strips

Delrin 100 (Natural)

• Standard unfilled grade
• Highest strength and stiffness
• FDA compliant for food contact
• Preferred for medical device manufacturing

Delrin 500 (Various Colors)

• General-purpose grade
• Good balance of properties
• Lower cost than specialty grades
• Common in consumer products

Delrin 100 AF (PTFE-filled)

• 13% PTFE internal lubricant
• Ultra-low friction coefficient
• Extended wear life
• Popular in conveyor components

Delrin Plastic Injection Molding: Process and Advantages

Le Delrin plastic injection molding has its distinctive benefits in high volume production. This procedure produces multifaceted components of a high quality consistency.

Step 1: Material Preparation

Drying of delrin pellets to eliminate moisture (less than 0.2 percent moisture content) takes place. This averts such defects as voids or surface imperfections.

Step 2: Heating and Melting

The injection molding machine turns the material into a heated temperature of 380-420°F (193-216°C) inside the barrel.

Step 3: Injection

The molten Delrin is subjected to pressure of 10,000-20,000 psi pressure injected into a precision mold cavity.

Step 4: Cooling

The part requires 10-60 seconds to cool depending on the thickness. The high cycle time of Delrin lowers the cost of production.

Step 5: Ejection

The resulting component is pressed out and may not need any additional processes.

CNC Machining Delrin: Best Practices and Services

CNC machining service providers love working with Delrin because it machines beautifully and produces high-quality parts with tight tolerances.

Why Delrin Excels in CNC Machining

Unlike softer plastics that melt or harder materials that cause excessive tool wear, Delrin offers:

• Clean chip formation – chips break away cleanly without gumming
• Excellent surface finish – achieves Ra 32 microinch or better
• Minimal tool wear – extends cutting tool life
• Tolérances serrées – holds ±0.001″ easily

Recommended Machining Parameters

Fonctionnement	Speed (SFM)	Vitesse d'alimentation	Type d'outil
Tournage	600-1000	0.010-0.020 ipr	Carbide insert
Fraisage	500-800	0.005-0.015 ipt	Carbide end mill
Forage	200-400	0.005-0.010 ipr	HSS or carbide drill
Threading	100-200	Single point	Carbide threading tool

Common Machined Parts

Industries rely on machined Delrin for:

• Gears and sprockets – Aerospace industry for actuator systems
• Bushings and bearings – Automotive industry for suspension components
• Wear strips and guides – Food processing industry for conveyor systems
• Composants des soupapes – Medical device industry for fluid handling
• Insulators and housings – Electronics industry for electrical components

Delrin Plastic Applications Across Industries

Delrin’s unique properties make it the material of choice for demanding applications across multiple sectors.

Automotive Industry Applications

Fuel System Components

• Fuel sender housings resist gasoline exposure
• Pump gears handle 50,000+ hours of operation
• Check valve seats maintain seal integrity
• Ford and GM specify Delrin for these parts (2023 data)

Door Lock Mechanisms

• Latch components operate silently
• Self-lubricating properties eliminate grease
• Temperature range from -40°F to 180°F
• Over 100,000 cycle life expectancy

Seat Belt Retractors

• High impact strength for crash safety
• Dimensional stability prevents binding
• Used by major safety equipment manufacturers

Aerospace Industry Applications

Interior Components

• Window shade mechanisms
• Seat adjustment gears
• Galley equipment parts
• Boeing and Airbus approve Delrin grades for cabin use

Electrical Insulators

• Connector housings for avionics
• Circuit breaker components
• Low moisture absorption prevents electrical failures
• Meets FAA flammability requirements

Medical Device Industry Applications

Instruments chirurgicaux

• Autoclavable grades withstand sterilization (up to 270°F)
• Lightweight compared to metal alternatives
• Non-corrosive in body fluid exposure
• Used by Stryker and Johnson & Johnson

Drug Delivery Devices

• Insulin pen components
• Inhaler actuators
• Pump housings and valves
• FDA-compliant grades available

Orthopedic Components

• Joint replacement trial components
• Surgical guides and jigs
• Custom patient-specific devices

Food Processing Industry Applications

Conveyor Components

• Wear strips for food contact conveyors
• Chain guides resistant to cleaning chemicals
• USDA and FDA approved grades
• Used by major food manufacturers like Tyson Foods

Processing Equipment

• Valve seats and seals
• Pump components
• Mixing vessel parts
• Withstands daily sanitizer exposure

Electronics Industry Applications

Connector Housings

• High dielectric strength (500 V/mil)
• Dimensional stability for tight tolerances
• Low moisture absorption prevents shorts
• Used by Apple and Samsung suppliers

Insulator Components

• Terminal blocks
• Relay housings
• Switch components

Common Mistakes to Avoid When Working with Delrin

Learning from others’ mistakes saves time and money. Here are the most common issues and how to prevent them.

Mistake #1: Using Flood Coolant in Machining

The Problem:When flooded with coolant, Delrin takes up moisture resulting in dimensional changes post machining. Components can be accurate on the machine and increase in size 0.002-0.005″ in a few days.

The Solution:

• Use air blast cooling only
• If coolant is necessary, use minimal mist
• Allow parts to stabilize 24 hours before final inspection
• Machine oversize by 0.001-0.002″ to compensate for growth

Mistake #2: Incorrect Material Storage

The Problem: Delrin should not be stored in wet conditions or be left without a carefully sealed cap as this leads to the absorption of moisture. This causes machining problems and dimensional instability

The Solution:

• Store material in sealed bags with desiccant
• Keep storage area below 60% relative humidity
• Allow material to acclimate 24 hours before machining
• Re-seal material immediately after cutting

Mistake #3: Using Dull Cutting Tools

The Problem: Aging tools heat too much, producing Delrin that melts and smears. This causes low-quality surface finish and dimensional inaccuracy.

The Solution:

• Use sharp carbide tooling exclusively
• Replace tools before they’re completely worn
• Monitor surface finish as tool wear indicator

Mistake #4: Over-Tightening Fasteners

The Problem: Delrin is a creepy material under continuous loading. Excessively tight screws lead to a dent and cracking in the long run.

The Solution:

• Use torque wrenches, not impact drivers
• Specify torque values 20-30% below metal equivalents
• Use large washers to distribute load
• Consider metal inserts for high-stress applications

Mistake #5: Ignoring Chemical Compatibility

The Problem: When we assume that every chemical is fine with Delrin, the result is that a part will fail. Acid and base are so strong and can easily degrade.

The Solution:

• Always consult chemical resistance charts
• Test material in actual service environment
• Consider alternative materials for questionable chemicals
• Request DuPont’s chemical resistance guide

Conclusion: Making the Right Choice with Delrin Plastic

Delrin plastic remains the material of choice in applications that require high performance and reliability by the engineers. Low friction and high strength coupled with high machinability and dimensional stability are aspects that render it invaluable in various industries.

When you need accuracy in your manufacturing, it is best to have an experienced CNC machining service provider who will help you get the Delrin parts just as you want them.

When you proceed with your next project, this guide can be used to make decisions on materials to use, processing, and supplier. The successful history of Delrin with 60 years experience is the reason why Delrin is the favorite of engineers across the world.

Ready to Start Your Delrin Project?

Need precision Delrin parts for your next project? Our CNC machining service specializes in working with engineering plastics including all grades of Delrin. We deliver tight-tolerance parts (±0.001″), excellent surface finishes, and fast turnaround times for both prototypes and production runs.

Contactez-nous dès aujourd'hui for a free quote on your Delrin machining project. Our experienced team serves the aerospace industry, automotive industry, medical device industry, and more with reliable, high-quality manufacturing services.

FAQS