Category: Plastic Machining

Vespel®: Extreme Polymer For Mission-Critical Applications

August 23, 2022

Push the Boundaries of High Performance and Sustainability With Precision Polyimides

When it comes to choosing a polymer for critical applications, there is no room for compromise. You need a material that can withstand the most challenging conditions while still providing the performance you need. For extreme environments, there is no better choice than DuPont’s Vespel® polyimide.

This unique polymer has been proven to exceed the performance of other materials in demanding applications, making it an essential component for mission-critical systems. With its exceptional strength and thermal stability, polyimide is ideal for use in aerospace and automotive engineering. So if you’re looking for a polymer that can handle anything, look no further than Vespel® polyimide.

 

Vespel® Works Overtime in Harsh, Demanding Environments

 

Image Source: Alan Turing Institute

 

Polyimide or Vespel® is a high-performance polymer made to withstand extreme environments where continuous friction and vast temperature variations are the norms. It’s most commonly found in engine components for the automotive and aerospace industries, as well as bushings and seals in industrial and energy applications. These mission-critical parts might come as small pieces, but they make a significant difference in weight, stability, and material longevity. Let’s take a closer look at how Vespel® benefits the Aerospace and Defense industry.

 

Aerospace applications of PI include:

  • compressors
  • fans
  • externals
  • nacelles
  • and engine oil system seals

 

The engine of an aircraft, whether for military or commercial use, is the most essential part of the plane. Keeping an aircraft in the sky and ensuring it reaches its destination is more than mission-critical; it’s non-negotiable. Vespel® meets the challenges of these environments, providing engineers with an innovative material advantage.

 

Vespel® Features and Benefits

Vespel® thrives in some of the most punishing environments like aircraft engines or gas-fired turbines. Here, we explore the top three features and benefits of Vespel®:

 

Feature Benefit
Vespel® is a lightweight alternative to metal. It offers a high tensile (8,750 psi) and flexural (16,000 psi) strength at one-half the weight of metal. Save weight – Vespel® offers astounding weight-saving benefits for aircraft by replacing metal or aluminum parts that add unnecessary weight.
Continuous service temperature – cryogenic temperatures to 260°C (500°F). Resist wear – With high temperatures, high speeds, and constant environmental fluctuations, Vespel® is a top choice for impact resistance and material preservation. It’s often found on bushings, fan blade root wear strips, as well as custom bumpers and pads.
Lower friction versus metal with a dynamic coefficient of 0.2 or less. Minimize friction losses – Components such as bushings need to withstand impact, cantilever loading, and accommodate designs with tight fits. Vespel slows part degradation and improves overall aircraft operability.

 

How Vespel® Compares to Other High-Performance Plastics

Vespel® is a high-performance plastic that is used in a variety of applications where strength, stability, and resistance to extreme temperatures are required. How does it stack up to other performance plastics like PEEK (Polyetheretherketone) and PEI (Polyethylenimine)?

Image Source: Performance Plastics Chart

 

When it comes to precision plastics, PEEK and PEI hold their own as exceptional engineering plastics. PEEK is often used in the medical field as a material for bone implants. PEI is most commonly used in high voltage electrical insulation applications due to its high dielectric strength. In comparison to PEEK and PEI, Vespel® has superior mechanical strength and flexibility.

 

Additionally, Vespel® is resistant to a wide range of chemicals, making it an ideal material for use in harsh environments. While Vespel® has many advantages over other high-performance plastics, it remains more expensive than these materials due to its complex manufacturing process.

 

Why Choose AIP for Your Vespel® Project?

When you’re working with a material like Vespel®, there is no margin for error. That’s why choosing a machining shop includes how they handle the material and how they handle your project from concept to completion.

 

38 Years of Precision Plastics Expertise

At AIP Precision Machining, we have over 38 years of experience in precision thermoplastics. Unlike other shops that may machine metals or other materials alongside plastics, our shop is 100% dedicated to plastics machining. It makes a difference in quality at the end of the day, as you can be assured that your machined parts will not deteriorate or crack from exposure to metal machining fluids.

 

Quality Assurance From Beginning to End

From start to finish, we take quality and compliance seriously. AIP is certified and adheres to the following regulations and standards:

  • ITAR
  • AS9100:2016
  • FDA Registered
  • ISO 13485.

 

Partnering With Leading Industry Suppliers

We have close ties with leading plastics manufacturers to give us even further insight and access to technical help in material selection, sizing, and machining protocols.

 

Through these partnerships, we offer a variety of materials available for expert machining services, including:

  • Vespel® SP and Vespel® SCP products
  • Ultem®
  • Ertalyte®
  • Radel®
  • Torlon®
  • Delrin®
  • and more

 

Unrivaled Expertise. Unparalleled Results

If you are interested in a quote for machined Vespel® or want a consultation for your precision project, give our team a call at (386) 274-5335 or click here. No matter how unique or complex your project may be, we are here to provide unrivaled expertise and guidance.

Find your next aerospace material for your mission-critical application.

 

 

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5 Advantages of PEEK Versus Metals

August 14, 2022

Here’s Why PEEK Is Kicking Metal to the Curb in Performance Engineering Applications

In the thermoplastic industry, there are a few materials that reign supreme. Among these, PEEK (polyetheretherketone) is king. This polymer has several advantages over traditional metal fabrication.

 

In this PEEK guide, we’re exploring why high-performance thermoplastic PEEK is kicking metal to the curb. PEEK has the strength and durability of metal, but at a fraction of the weight and resists chemicals and hydrolysis. It’s these qualities that allow PEEK polymers to replace metals in precision engineered components.

 

Industries That Benefit From PEEK Versus Metals

Let’s take a look at how PEEK improves performance and functionality in some leading mission-critical industries.

 

Aerospace and Defense

The aerospace and defense sector often replaces aluminum parts in favor of PEEK for weight reduction and its tolerance to high temperatures. The benefits include fuel reduction and longer part lifespan. PEEK is also a safer material to use, since its low conductivity allows for lower heat build-up.

Another strength of PEEK over metals is inherent to all plastics. PEEK has exceptional thermal and electrical insulative properties, which comes in handy with equipment designed to undergo extreme stress. Thermal insulation ensures the pieces won’t melt or damage neighboring equipment, much in the same way electrical insulation will stop damaging currents of electricity from harming critical systems on the plane.

 

Medical and Life Sciences

Material choice and design functionality make a vast difference for surgical instrumentation in the medical field. As a chemically inert thermoplastic, PEEK wins over metal in areas where chemicals may be present. Furthermore, PEEK offers radiolucency for scanning machines that need to produce clear readings of the interior of the body. Metals often muddle or interfere with the imaging.

PEEK has passed all ISO 10993 biocompatibility tests for both short and long-term implants. However, because PEEK is so durable, it’s generally only recommended for long-term implants.

 

Oil and Gas

With excellent resistance to abrasion, chemicals, and hydrolysis, PEEK thrives in tough environments, such as offshore oil rigs. The equipment in the oil and gas industry is placed deep underground where conditions, chemical reactions, and forces are unpredictable. PEEK is a common material for seals and valve plates to ensure a fail-safe environment.

 

Precision Devices

The use of PEEK in precision devices is not just for its elevated level of structural rigidity but also because it provides electrical insulation. Connector covers and transducer cases are made from this material to avoid interference with signals passing through the wires within a device. Since this industry engineers streamlined lighter designs, PEEK is an ideal choice for weight reduction.

 

Weight Reduction

 

 

One of the leading reasons for choosing PEEK over metallic competitors like aluminum or titanium is its lightweight properties. This has opened the door to many engineering material innovations.

 

One area, in particular, is aerospace and defense. Using PEEK over metals can cut fuel usage and create weight savings of up to 60 percent. This translates to lower annual fuel costs, reduced emissions, lower carbon footprints, and extended flight ranges.

 

Enhanced Performance

Polyetheretherketone PEEK provides performance-enhanced products by extending service life and resistance to corrosion with a lower coefficient of friction. In dynamic applications such as bearings or seals, this tough plastic can increase load capacity while also operating at temperatures of up to 480°F. This translates to fewer instances of maintenance and a longer overall performance from the system as a whole.

 

Design Freedom

One of the greatest strengths of thermoplastics is their contribution to design processes. PEEK can be CNC machined, injection molded, and even 3D printed. This type of versatility enables greater design freedom for complex engineering and custom geometries. Thermoplastic PEEK versus metals can be machined to specific tolerances as low as 0.002mm with the right machining shop.

 

High Purity

 

 

The medical sector demands nothing less than complete purity from materials, especially in the case of orthopedic implants, for instance. Metallosis is a real concern for metal implants as they can leach into the body. PEEK ,including Glass-Filled, PEEK-HT (High Temperature), and PEEK-UHP (Ultra-High Purity) are all desirable alternatives for metal applications in food processing, biomedical, and semiconductors.

 

Total Lower System Cost

When it comes to individual material costs, PEEK can range from 20 to 30 times the cost of some metals like stainless steel. Yet, the stand-alone cost cannot be the main factor in high-performance design decisions. Engineers look at the big picture in the long run of material value.

With the overall improvement in material performance, longevity, weight reduction, and purity factors, PEEK significantly decreases the cost of a total system. This is why it’s a popular material choice for high-performance engineering components.

 

The Global Leader for Performance PEEK Components

Precision and performance are what we strive for at AIP Precision Machining. With decades of experience in the industry, our dedicated craftsmen and close ties with leading plastic manufacturers allow us to provide unrivaled knowledge and consulting services in material selection, sizing, manufacturing techniques, and more to best meet your project’s needs.

If you are looking to use PEEK for your precision project, reach out to our team for a consultation. We are here to help solve your plastics puzzle and provide technical expertise and diligent craftsmanship from concept to completion.

 

Thinking about PEEK for your precision project?

Discover what this polymer can do

 

 

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Why it’s essential to have AS9100D for aerospace manufacturing

July 27, 2022

Not just a standard…THE standard

 

AS9100D Logo

AS9100 is a company level certification based on the ISO 9001 quality standard requirements, but with additional requirements based on the needs of the aerospace industry. These satisfy both ISO 9001 quality standards and DOD, NASA and FAA requirements.

Companies in the business of manufacturing parts and components for both federal and civil enterprises in the aerospace sector are required to provide the highest level of quality assurance for their manufacturing techniques. Why? A single malfunctioning part on an aircraft could have a devastating impact on the entire apparatus. Not only is it dangerous for operation, but maintenance for an unknown malfunction is costly in time, budget, and resources.

That’s why the Aerospace and Defense industry has developed a strict quality management process for manufacturers to follow known as AS9100D. Here’s why it’s essential for precision plastics manufacturers to have an AS9100D certification.

 

Benefits of AS9100D Certification for Aerospace Machining Standards

 

Satellite orbiting Earth

Global Standard

An AS9100D certification is internationally recognized around the world, but with different numbering conventions. The International Standards Organization equivalent is ISO 9001. Major aerospace manufacturers and suppliers worldwide require compliance and/or registration to AS9100 as a condition of doing business with them.

Quality Assurance

When it comes to machining for the Aerospace and Defense sector, quality and consistency in manufacturing techniques are paramount. An AS9100D certification ensures that machining processes, product handling, storage, and shipping are all accounted for in a facility’s processes.

Requirement for Business

Material suppliers that wish to serve the Aviation, Space and Defense (AS&D) industry must attain this certification to prove the high level of competence required by the industry.

Works at the Federal & Civil Enterprise Level

The guidance recommended by AS9100D satisfies standards for NASA, DOD, and FAA. Whether a manufacturer is working with a federal-level defense contractor or a commercial jet line, an AS9100D certification shows commitment to quality processes around manufacturing aerospace parts.

 

How to get AS9100D certified

Certifying your machining processes are safe and consistent is a requirement for doing business in the Aerospace and Defense sector. In order to get an AS9100D certification, a company must prove its ability to remeasure and reassess a product during the construction phase, ensuring uniformity among mass-produced items. The certification does not focus on product quality, but product consistency in the end result. Here are a few areas to pay attention to if seeking the certification for manufacturing aerospace materials:

  • Emphasis on Risk Management
  • Attention to “Special Requirements”
  • Attention to “Critical Items”
  • Measure: Requirements conformance
  • Measure: Delivery performance
  • Adopt Proven Product Development Processes
  • Eliminate “recurring corrective actions”

 

 

Expert Aerospace Machining for Aircraft Plastic and Composite Parts

Jet fighters, satellites, and in particular spaceships need the highest level of precision engineering to accomplish their goals. To that end, machining plastic components to these exacting standards isn’t easy…it’s precise. At AIP, we’ve been working in precision plastics machining for over three decades. Our projects include major aerospace companies like Lockheed Martin and GE, all demanding the highest level of risk assessment and quality management throughout the entire machining process.

To that end, we are setting the standard for Aerospace and Defense plastic machining. In aerospace and defense applications, adherence to stringent industry specifications is something AIP takes seriously. AIP is a certified and registered ITAR facility and AS9100D certified. We are capable of satisfying all customer DOD, NASA and FAA quality requirements recommended by our OEM customers. We understand the need for lot and batch traceability, as well as materials that can survive extreme operating environments.

Every product we develop is made from carefully selected materials for your specific application and needs. Our high-performance thermoplastics and compounds made for the aerospace and defense industry feature:

  • Chemical resistance
  • Conductive or insulative properties
  • Corrosion protection
  • Extreme Precision tolerance (up to 0.002 mm)
  • Finished smooth surface
  • High-temperature resistance (exceeding 750 F, 400C)
  • Lightweight
  • No stress-induced distortion
  • Radar absorption

Want to contact us about aerospace manufacturing?

Get in touch with us online, or see our  AD9100D:2016 certification.

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What Does It Mean To Be As9100 Certified?

April 7, 2022

What Is an AS9100 Certification?

 

Developed by the International Aerospace Quality Group (IAQG), the AS9100 is an international quality management certification. Material suppliers that wish to serve the Aviation, Space and Defense (AS&D) industry must attain this certification to prove the high level of competence required by the industry. AS9100 applies to both military and civil businesses.

 

The standard is accepted worldwide, with different parts of the world having their own numbering systems, but crucially, they all prove the same level of competence. Whether a company is made up of thousands of individuals or just one person, it will require the AS9100 to provide supplies to the aerospace industry.

 

However, just because a company could theoretically consist of one person doesn’t mean the certification is attained on an individual level. The AS9100 is a company-wide certification, meaning that it can only be acquired and applied to a company. So, if Darrel is the sole owner and employee of ABCD Inc. and earns the certification, Darrel isn’t certified, ABCD Inc. is.

 

Becoming AS9100 certified also means earning an ISO 9001 certification along the way. The reason is that the AS9100 is an extension of the ISO 9001 with an additional focus on aerospace regulations. So, companies that achieve an AS9100 will be qualified in multiple quality management systems.

 

Finally, the AS9100 certification is not a standard of product quality. Rather, it’s a standard of the processes taken to ensure a quality, consistent product. To attain the certification, a company must prove its ability to remeasure and reassess a product during the construction phase, ensuring uniformity among mass-produced items. The certificate may not focus on product quality, but the end result is the same.

 

Why Must a Plastics Machining Facility Be AS9100 Certified?
 

 
The quick and easy answer is that the certification is required by many aerospace manufacturers. If a plastics machining facility wishes to do business in this industry, attaining the certificate is an entry-level requirement.

 

The longer answer is that several large aerospace entities endorse the certification. Some of these groups include the U.S. Department of Defense (DoD), the Federal Aviation Administration (FAA), and the National Aeronautics and Space Administration (NASA). To become an official supplier to any of these entities, a plastics machining facility Must have the certification.

 

But why do these institutions require the certification? Jet fighters, satellites, and especially spaceships need the highest level of precision engineering to accomplish their tasks; creating plastic components to such exacting standards isn’t easy. So, every stage of the creation process, all the way down to the small plastic materials, must go through a strenuous quality management system to ensure a low-risk management level for the final product.

 

What About AIP Precision Machining Allows Us to Achieve an AS9100 Certification?

 

 
We’ve made it no secret that precision machining is vital to who we are as a company. So much so that we’ve put it in our name! With AIP Precision Machining, you’re investing in a partner that not only understands the needs of the industry but has the decades of experience needed to perfect the processes that go into creating the perfect components.

 

With the regulatory requirements being as stringent as they are, there is no room for the kind of mistakes human factors tend to introduce to the manufacturing process. That’s why we involve several quality control checks in line with AS9100’s requirements during the creation process to guarantee the level of service quality expected from us.

 

We’ve satisfied several aerospace and defense industry requirements in the past, so we know the kind of qualities these industries need in their components. Our highly trained engineers, machinists, and programmers have been specially trained to create components with the types of qualities aerospace and defense organizations look for:

 

  • Lightweight
  • Durable
  • Extreme Temperature Resistance
  • And much more.

 

At AIP Precision Machining, product and service quality assurance is the norm for our customers and ourselves. We are proud to offer the aerospace industry our services in machining quality components. We have proven time and again that we are quick to deliver, cost-effective, and, more often than not, surpass customer satisfaction. Our safe and reliable products meet all statutory and regulatory requirements and are guaranteed to help see your project through to the end.

 

To contact us, call our main office at (386) 274-5335 or visit our website to schedule a consultation. With AIP, you have a manufacturing partner you can rely on.

   

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AIP Is Your One-Stop Shop For Reliable And Precise Medical Plastics

March 14, 2022

Few industries require precision and reliability as much as the medical industry. When lives are literally on the line, you can’t risk the chance of arming medical professionals with equipment that’s anything less than perfect.

 

There’s also the burden of choice to deal with. The medical device industry has seen plastics soaring in use due to their numerous benefits, but it’s those same qualities that can make them so frustrating to machine. Choosing the best possible polymer for your needs requires trained professionals that know the options like the back of their hands.

 

So who can you trust? The search for a high-quality polymer manufacturer begins and ends with AIP.

 

Plastic Components Machined to Perfection

 

We at AIP pride ourselves on the level of precision we can achieve when manufacturing polymers for the health care industry. We work at the highest levels state-of-the-art machinery will provide, allowing us to construct medical components within ten-thousandths of an inch precision. With quality checks completed after every stage of the development process, we can guarantee a quality product every time.

 

Reusable Medical Plastics

 

An unfortunate byproduct of increased plastics in the medical industry is the expanding weight of medical waste. As creators of polymer materials, we’re especially conscious of unnecessary waste, which is why our materials are built to last.

 

Our high-performance precision plastic parts offer the medical industry all the advantages of metal, along with the crucial ability to withstand repeated autoclave sterilization sessions. Furthermore, many of our polymers have a low coefficient of friction, making the steaming process faster, and putting them back in the hands of medical professionals more efficiently.

 

Quality Assured

Precision and reliability go hand in hand, and we consider precision important enough to put it in our name. That’s why our materials are put through a quality check through every step of the creation process. But we go one step further than the competition.

 

Many polymer manufacturers double as metal producers, and they tend to create their products together in the same warehouse. The problem is that many of the ingredients used to treat metal are hazardous to the structural integrity of plastics. If they mix, the plastic’s lifespan falls to only a short few months before premature cracks begin to show.

 

We decided long ago that the risk to your product’s quality wasn’t worth it. Our main production facility specializes in polymers, removing the threat of metal contamination entirely from the equation. All our clients consider reliability vital, but when creating components for medical devices, there’s an increased ethical onus on us to build an exceptional product, and we respect that.

 

The Many Roles Medical Grade Plastics Must Fill

 

While there are several kinds of medical-grade polymers, the choices skyrocket when you consider that each has dozens of different grades suited to specific tasks. Crucially, they must all be safe for human contact, but some of the other qualities our polymers can satisfy are:

 

  • Radiolucency
  • Corrosion Protection
  • Extreme Tolerance (up to 0.002 mm)
  • High Dielectric Strength
  • Sterilization Compatibility
  • Lightweight Properties
  • Extreme Thermal Performance
  • Extreme Chemical Resistance
  • Extreme Low Friction

 

Our materials are relied upon in some of the most delicate medical applications. Surgical instruments, orthopedic equipment, even spinal and dental implants utilize our medical-grade plastic parts.

 

 

The Materials and Their Qualities

With each plastic boasting different strengths and weaknesses, you need to know which one will suit your needs the best. Some of our options include:

 

  • PEEK – One of the most diverse materials, thanks to its many different grades; it boasts high strength and excellent resistance to chemicals, steam, and abrasion. PEEK is frequently utilized in both medical implants and instruments.
  • PPSU (Polyphenylsulfone) – Extremely tough and able to withstand nearly unlimited sessions of steam autoclave sessions. PPSU is the perfect material to make reusable medical instruments with.
  • UHMW-PE (Ultra-High Molecular Weight Polyethylene) – Significantly higher impact strength and abrasion resistance compared to most plastics on the market. Its low coefficient of friction due to its self-lubricating, non-stick surface makes it a great candidate for hip and knee joint replacement components

 

Ease of Access and the Cost-Efficient Choice

 

With Covid placing an incredible weight on material transportation, many metals and other materials have become difficult or simply too expensive to get a hold of. Polymers don’t suffer the same difficulties, as they can be readily manufactured anywhere in the world and remain cost-effective.

 

 

By utilizing more plastic materials in your medical equipment, you safeguard your business against strained supply lines and expensive materials, allowing you to keep your costs and your prices below the competition.

 

AIP Is Here for Your Medical Plastic Needs

 

AIP is registered with the FDA and ISO 13485:2016 certified. Our plastics are processed with the strictest hygienic procedures, and these quality assurance procedures ensure you’ll receive the exact materials you need for the job. We’re proud to be of service to health care providers by playing a part in the tools they use.

 

To contact us, call our main office at (386) 274-5335 or visit our website to schedule a consultation. With AIP, you have a manufacturing partner you can rely on.

   

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Machining Acrylonitrile Butadiene Styrene (ABS) A Plastics Guide

June 22, 2021

An Informational Brief on Polymer Machining

 

Known for its ease of machining, coloring and adaptability to additives, ABS is a versatile performance thermoplastic.  While it may be used in household toys, it is also used for mission critical applications like electrical insulators and automotive interior and exterior parts.

 

AIP has over 37 years of experience machining complex components from thermoplastics like Acrylonitrile Butadiene Styrene (ABS).  In this insightful technical brief, we will discuss what goes into machining ABS and how it differs from other manufacturing options such as metal machining, injection molding, and 3D printing.

 

Properties of ABS

 

Machinists should keep data on the properties of the thermoplastics they use.  This aids in selecting the right material for a project.  Also, it helps determine if the material is a good candidate for the end-use.  Below are some of the key characteristics of Acrylonitrile Butadiene Styrene (ABS):

 

Key Properties

  • Impact resistance
  • Chemical resistance
  • Ideal electrical insulator with added moisture resistance
  • Good strength and stiffness
  • Platable grades
  • Excellent aesthetic qualities
  • Colorable
  • Various gloss levels (Matte to High Gloss)

 

Description

ABS is one of the most common thermoplastic polymers manufactured. It is relatively cheap compared to other performance thermoplastics, such as, PEEK or VESPEL.

 

It provides good mechanical properties, including, impact resistance, toughness and rigidity compared to other common polymers. It is also easy to modify with additives to improve any of its properties. It is often a polymer of choice where aesthetics and color are concerned, since its natural color is translucent ivory to white. Pigments and additives are often added to this resin to improve the qualities based on the project needs.

 

Two major categories could be ABS for extrusion and ABS for injection molding, then high and medium impact resistance. Generally, ABS would have useful characteristics within a temperature range from −20 to 80 °C (−4 to 176 °F). As an amorphous polymer, it does not have a true melting point.

 

The table below displays an overview of the material properties, units and values for machining ABS:

 

Material Property Units Value
Tensile Elongation at Break @73 F % 20
Flexural Modulus of Elasticity @ 73 F psi 340000
Tensile Modulus of Elasticity @ 73 F psi 346000
Flexural Strength @ 73 F psi 9300
Specific Gravity @73 F ASTM D792 1.04
Tensile Strength @73 F, (ult)/(yld) psi 5500 (ult)
Notched Izod Impact @73 F ft-lb/in of notch 7.0
Heat Deflection Temperature @ 264 psi F 220
Flammability Rating UL94 HB(6.10mm)
Coefficient of Linear Thermal Expansion @73 F in/in/F 5.2E-05
Dielectric Strength, Short Term Volts/mil 450
Water Absorption, Immersion, 24 hours
Water Absorption, Saturation		 % by weight
% by weight		 0.30
0.70

 

Applications of ABS

 

ABS is mostly found in a wide variety of consumer products. Some of which include – Legos®, recorders and other musical instruments, golf club heads, household vacuums, and so on. ABS is a household staple for many consumer goods.

 

It also finds several end-use applications in the industrial sector. Applications include – automotive trim and components, inhalers, tendon prostheses, drug-delivery system tracheal tubes, enclosures for electrical and electronic assemblies, protective headgear and more.

 

Common Applications

  • Structural components
  • Automotive interior and exterior parts
  • Medical devices
  • Electrical components and assemblies
  • Toys
  • Housings/covers
  • Kitchen appliances

 

AIP Machining Capabilities: Unrivaled Expertise

 

Our close ties with the industry’s leading plastics manufacturers give us even further insight and access to technical help in material selection, sizing and manufacturing procedures. If you are looking for a trademarked material for your project, we have a host of material bases available for expert machining. Whatever your application, our machinists can help you in material selection, sizing and manufacturing techniques from concept to completion.

 

Our Suppliers

 

Machining ABS

 

Annealing ABS

As with any CNC machined part, annealing and stress-relieving is crucial to the machining process. Coolants, lubricants and trained procedures prevent cracking and crazing in a precision machined component. We recommend slow heating and cooling during the annealing process of thermoplastics. This reduces the chances of these stresses occurring from the heat generating during machining polymers like ABS. Our AIP machinists use computer controlled annealing ovens for the highest quality precision temperatures and time control. .

 

Machining ABS

PVC can be injection molded, extruded or thermoformed.  At AIP, we CNC machine compounded PVC.  For the best results, use sharp tools, avoid excessive clamping and cutting forces and use coolants to prevent overheating.  We recommend non-aromatic, water-soluble coolants because they are most suitable for ideal surface finishes and close tolerances. These include pressurized air and spray mists. Coolants also preserve and extend the life of tools.  These guidelines are general and are not a substitute for a conversation with your machinist.  For further information, speak to a CNC machinist at AIP to get specific machining information on PVC and other performance thermoplastics.

 

Although it is often blow molded, ABS can be CNC machined and milled for precision parts. ABS is manufactured in a variety of grades, but for precision machining of ABS structural parts, it is recommended to use Machine Grade ABS. For the best results, use sharp tools, avoid excessive clamping and cutting forces and use coolants to prevent overheating. We recommend non-aromatic, water-soluble coolants because they are most suitable for ideal surface finishes and close tolerances. These include pressurized air and spray mists. Coolants have the additional benefit of extending tool life as well.

 

Some companies machine both metals and plastics, which has detrimental outcomes for machined polymer products. Many past experiences have shown parts going to customer without cracks, only to develop surface cracks and warping over time due to exposure to metal machine shop fluids. Be sure to use a facility like AIP that only machines polymers.

 

Preventing Contamination

Contamination is a serious concern when machining polymer components for technically demanding industries such as aerospace and medical sciences. To ensure the highest level of sanitation down to the sub-molecular level, AIP Precision Machining designs, heat-treats, and machines only plastics with any sub-manufactured metalwork processed outside our facility. This allows us to de-risk the process from metallic cross contamination.

 

ABS Machining Guide: Supportive Information

 

Quality Assurance Certifications
Miscellaneous Materials

 

How will the heat from your machining project affect your project? Make sure to talk to your machinist about the CLTE of your machined part.

 

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Understanding Heat Deflection Temperature (HDT) of Plastics

June 8, 2021

What is HDT?

 

The Heat Deflection Temperature (HDT), or Heat Distortion Temperature, is a measure of a polymer’s resistance to alteration under a given load at an elevated temperature.  It is also known as the ‘deflection temperature under load’ (DTUL) or ‘heat deflection temperature under load (HDTUL)’.  Basically, it tests the stiffness of a material as the temperature increases.

 

It is the temperature at which a polymer test bar will be bent at 0.25 mm under a given weight.  It is one of the two basic test methods for assigning a value to the performance of a plastic at high temperature.  The 0.25mm value is arbitrary and does not have any significant meaning.

 

Why is HDT significant?

 

As with any machined part, during the design phase, it is critical for a machinist to know how a material will react to heat produced while machining occurs.  Tools produce heat when they come in contact with materials and plastics have a tendency to move with heat.  In order to get a finished product with the right dimensions and tolerances, it is important to understand the heat deflection temperature of a given polymer.

 

Other reasons include:

  • HDT represents a value which can be used to compare different materials with each other
  • It is applied in product design, engineering and manufacture of products using thermoplastic components
  • A higher HDT temperature means a faster molding process in injection molding processes

 

Tests to Measure Heat Deflection Temperatures of Plastics

 

The American Society for Testing and Materials, or ASTM, standard for measuring HDT is called ASTM D 648; this standard is equivalent to the ISO 75.

 

The two common loads used in heat deflection testing are:

  • 0.46 MPa (67 psi) – this load is usually for softer grades of plastic like polyethylene (PE) or LDPE.
  • 1.8 MPa (264 psi) – this load is used for more durable grades of plastic like PEEK or polycarbonate (PC).

 

There are tests performed at higher loads such as 5.0 MPa (725 psi) or 8.0 MPa (1160 psi), but we won’t discuss them in this brief.

 

Limitations that are associated with the determination of the HDT is that the sample is not thermally isotropic and, in thick samples in particular, will contain a temperature gradient.

 

During the ASTM D 648 test, a testing rod made of the selected polymer is placed on an apparatus like the one in the diagram below.

 

 

 

Source: SEKISUI Polymer Innovation
 

The bar is molded a specific thickness and width.  The sample is then submerged in oil while the temperature incrementally increases (usually about 2 oC per minute).  The constant applied force, or load, is pressed to the midpoint of the test bar.  The temperature at which a bar of material is deformed 0.25mm is recorded as the HDT.

 

HDT at 1.8 Mpa (264 psi) Values for Common Polymers

 

 

Polymer Name Min Value (o C) Max Value (o C)
ABS – Acrylonitrile butadiene styrene 88 100
PA – Nylon Polyamide, 66 30% Glass Fiber 230 255
PAI – Polyamide-Imides (TORLON) 275 280
PBI – Polybenzimidazole (CELAZOLE) – 426.6
PC – Polycarbonate, high heat 140 180
PE – Polyethylene, 30% glass fiber 121 121
PEEK – Polyetheretherketone 150 160
PEI – Polyetherimide (ULTEM) 190 200
PP – Polypropylene (30-40% Glass fiber-reinforced) 125 140
PP – Polypropylene Homopolymer/Copolymer 50 60
PS – Polystyrene, high heat 85 100
PSU – Polysulfone 160 174
PTFE – Polytetrafluorethylene 45 50
PVC – Polyvinyl chloride, rigid 54 75
PVDF – Polyvinylidene fluoride (KYNAR) 50 125

 

Factors That Influence HDT

 

The HDT gives a short-term performance under load at elevated temperatures for a polymer by measuring the effect of temperature on stiffness.  Yet, this is only an estimate and should not be used to predict how the final part or component will perform.

 

Other factors will significantly influence the final thermal performance of an application.

 

These factors include:

  • The time of exposure to elevated temperature
  • The rate of temperature increase
  • The part geometry

 

The HDT measure for a specific polymer grade also depends on the base resin and the presence of reinforcing agents, fillers or plasticizers.

 

For instance, in the chart above, the homopolymer or copolymer of polypropylene has a HDT value range of 50-60 oC. Compare that value to the 30-40% glass-fiber reinforced grade of polypropylene, which is more than double the temperature (125-140 oC).  A factor like this would influence the material choice for a designer wanting to use polypropylene for the end use product.

 

A combination of additives will always have a different effect on the HDT and the performance of a polymer overall.

 

  • Reinforced and filled grades have a higher HDT (harder and stiffer under the heat)
  • Plasticizers decrease HDT by making the polymer softer and more flexible

 

AIP:  Unmatched Precision.  Unrivaled Experience

 

Data charts can give you the heat deflection temperature, glass transition and other values.  However, a chart can give a general idea of these values, but an entire data set with the curve of a material is the best way to determine the right material for your project.

 

Be sure to work with a plastics machining company that can provide you a wide range of data on the HDT and other values of polymers and composites.  Your machinist will be able to give you a detailed response on how the heat deflection temperature will affect your project’s design and functionality.  Talk to one our engineers at AIP about your project design, and we will work with you to provide unrivaled expertise from your project’s initial concept to completion.

 

Supporting Materials

Certifications and Technical Data Resources

 

Learn more about the material properties we consider when
working on a precision plastics machining project.

 

Read our blog on the CUT of Polymers
 

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MACHINING PVC: A PLASTICS GUIDE

May 18, 2021

An Informational Brief on Polymer Machining

 

PVC, or polyvinyl chloride, is a rigid material that exhibits high corrosion resistance, high chemical resistance, low moisture absorption and excellent dielectric strength.  These qualities make it a choice material for a wide range of industries, including:  medical devices, industrial/construction components and everyday household items.  It is the world’s third largest thermoplastic material by volume only after polyethylene and polypropylene.

 

AIP has over 37 years of experience machining complex components from thermoplastics like PVC.  In this insightful technical brief, we will discuss what goes into machining PVC and how it differs from other manufacturing options such as metal machining, injection molding, and 3D printing.

 

Properties of PVC

 

All machine shops should keep data on the properties of the thermoplastics and materials they use.  The data helps in selecting the right material for a project and a material’s suitability for the end-use product.  Below are some of the key characteristics of PVC:

 

Key Properties

  • Good insultation
  • Dielectric strength
  • Durable
  • Flame Retardant
  • Low maintenance and long life span
  • Abrasion resistant
  • Light-weight
  • Chemical resistance

 

Description

Polyvinyl Chloride (PVC or vinyl) is a highly durable thermoplastic material.  It is versatile and economical for applications in medical, construction, industrial and consumer end use markets.

 

PVC has excellent dielectric strength which makes it a good insultation material.  It is also resistant to weathering, chemical rotting, corrosion, shock and abrasion – therefore, a preferred material choice for long-life and outdoor products.  PVC is resistant to all inorganic chemicals. It has very good resistance against diluted acids, diluted alkalis and aliphatic hydrocarbons. Attacked by ketones; some grades swollen or attacked by chlorinated and aromatic hydrocarbons, esters, some aromatic ethers and amines, and nitro- compounds.

 

It is available in two forms – rigid and flexible – but it is often mixed with additives to enhance properties and improve machineability.

 

The table below displays an overview of the material properties, units and values for machining PVC Gray Type 1:

 

Material Property Units Value
Tensile Elongation at Break @73 F % –
Flexural Modulus of Elasticity @ 73 F psi 455000
Tensile Modulus of Elasticity @ 73 F psi 392000
Flexural Strength @ 73 F psi –
Specific Gravity @73 F ASTM D792 1.43
Tensile Strength @73 F, (ult)/(yld) psi 7300 (yld)
Notched Izod Impact @73 F ft-lb/in of notch 0.7
Heat Deflection Temperature @ 264 psi F 169
Flammability Rating UL94 –
Coefficient of Linear Thermal Expansion @73 F in/in/F E-831(TMA)
Dielectric Strength, Short Term Volts/mil –
Water Absorption, Immersion, 24
Water Absorption, Saturation		 % by weight
% by weight		 –
–

 

Applications of PVC

 

PVC comes in two general forms – rigid and flexible.  However, it can be combined with several different materials to enhance its qualities for use in a range of applications from medical devices to industrial construction components.  Here is a list of the most common applications:

 

Common Applications

 

Application Rigid PVC Flexible PVC
Construction Window Frames, Pipes, House Siding, Ports, Roofing Waterproof Membranes, Cable Insultations, Roof Lining, Greenhouses
Domestic Curtain Rails, Drawer Sides, aminates, Audio and Videotape Cases, Records Flooring, Wall Coverings, Shower Curtains, Leather Cloth, Hosepipes
Packaging Bottles, Blister Packs, Transparent Packs and Punnets Cling Film
Transport Car Seat Backs Under Seal, Roof Linings, Leather Cloth Upholstery, Wiring Insultation, Window Seals, Decorative Trim
Medical – Oxygen Tents, Bags and Tubing For Blood Transfusions, Drips and Dialysis Liquids
Clothing Safety Equipment Waterproofs for Fishermen and Emergency Services, Life-Jackets, Shoes, Aprons and Baby Pants
Electrical Insultation pipes, jacketing, electricity distribution boxes, switches, transparent distributor box housings, plug housings and battery terminals Cable and wire insultation, plugs, cable jackets, sockets, sable heads and distributors
Other Credit Cards, Traffic Signage Conveyor Belts, Inflatables, sports goods, toys, garden hoses

 

AIP Machining Capabilities: Unrivaled Expertise

 

Our close ties with the industry’s leading plastics manufacturers give us even further insight and access to technical help in material selection, sizing and manufacturing procedures.  If you are looking for a trademarked material for your project, we have a host of material bases available for expert machining.  Whatever your application, our machinists can help you in material selection, sizing and manufacturing techniques from concept to completion.

 

Machining PVC

 

Annealing PVC

Annealing and stress-relieving prevents cracking and crazing in a precision machined component with lubricants, cooling agents and trained procedures.  We recommend slow heating and cooling during the annealing process of thermoplastics.  This reduces the chances of these stresses occurring from the heat generating during machining polymers like PVC.  Our AIP machinists use computer controlled annealing ovens for the highest quality precision temperatures and time control.  If you have a specific question about the annealing process for PVC or other thermoplastics, our machinists at AIP can provide an in-depth consultation.

 

Machining PVC

PVC can be injection molded, extruded or thermoformed.  At AIP, we CNC machine compounded PVC.  For the best results, use sharp tools, avoid excessive clamping and cutting forces and use coolants to prevent overheating.  We recommend non-aromatic, water-soluble coolants because they are most suitable for ideal surface finishes and close tolerances. These include pressurized air and spray mists. Coolants also preserve and extend the life of tools.  These guidelines are general and are not a substitute for a conversation with your machinist.  For further information, speak to a CNC machinist at AIP to get specific machining information on PVC and other performance thermoplastics.

 

Some companies machine both metals and plastics, which has detrimental outcomes for machined polymer products.  Past experiences have shown parts going to customer without cracks, only to develop surface cracks and warping over time due to exposure to metal machine shop fluids. Be sure to use a facility like AIP that only machines polymers.

 

Preventing Contamination

Contamination is a serious concern when machining polymer components for technically demanding industries such as aerospace and medical sciences. To ensure the highest level of sanitation down to the sub-molecular level, AIP Precision Machining designs, heat-treats, and machines only plastics with any sub-manufactured metalwork processed outside our facility.  This allows us to de-risk the process from metallic cross contamination.

 

PVC Machining Guide: Supportive Information

 

Quality Assurance Certifications
Miscellaneous Materials

 

Looking for more plastics machining guides on polymers with chemical resistance?

 

Read Our PCTFE Machining Guide
 

 

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How Continuous Use Temperature Relates to the Stability of a Machined Polymer

April 27, 2021

The continuous service temperature, or continuous use temperature (CUT), is the maximum ambient service temperature in air that a material can withstand and maintain 50% of its initial physical properties after long-term service.

 

What is long-term service?  It’s defined as 100,000 hours of service – well over 11 years, if used 24 hours a day, 365 days a year.  The continuous use temperature property tells machinists and users what will happen to a part over the course of roughly 11 years of continuous use.  It’s the temperature at which the polymer will degrade, embrittle and start to break down.

 

It is important for the designers, engineers and users to take this measurement into consideration for CNC machining.  During the design phase, this not only helps with initial material selection, but plays a role in predicting the life span of a part.  At AIP, we take great care in providing unrivaled results to ensure the optimal dimensions and properties for machined polymers and composites.  Join us in this technical brief as we give an in-depth explanation of the continuous use temperature for machined polymers.

 

What Affects Continuous Use Temperature?

 

The base material polymer structure affects the continuous use temperature of a machined part.  The time that is involved and the loading levels that are used in the testing can affect the CUT value.  Also, additives and reinforcements should be taken into consideration.  They may have an effect on the maximum continuous use temperature value.

 

Tests to Measure Continuous Use Temperature of Plastics

 

The continuous use temperature is measured in degrees Celsius (o C) or Fahrenheit (o F).  One of the common tests used to compare different materials in terms of continuous use temperature is the Underwriter Laboratory (UL) Relative Thermal Index or RTI.

 

UL 746B

This test method is used to determine RTI values.  The RTI is based on a loss of properties of the plastic versus time. In general, when the plastic is exposed to this maximum continuous use temperature – good, long-term performance is observed. However, it does not consider short-term thermal spikes.

 

RTI gives an indication of the aging temperature that a material can endure for 100,000 hours and still retain at least half of the initial property being measured. However, different properties for materials decay at dissimilar rates. This is the primary reason why often RTI values are associated with a particular property and the related CUTs are given as a range of values rather than as a single value.

 

Determination of RTI Value

  1. Groups of test pieces are placed in ovens at four different pre-set temperatures.
  2. At specified time intervals, the test pieces are taken out of the ovens and tested for mechanical and electrical properties of interest.
  3. The results are plotted on a property versus time graph until the property that is being tested declines to 50 percent or less of its initial value.

 

In this analysis, the 50 percent value of the property is referred to as the half-life of that particular property. The half-life values are then, plotted against the reciprocal of the absolute aging temperature. This plot results in a straight line that can be extrapolated, if needed, to indicate the half-life of the property at other temperatures.

 

The results that are obtained in this testing procedure can also be compared to a material with a known aging performance.

 

Types of RTI

There are three general classes of properties that are associated with the RTI.  The three values for a particular polymer are often different from each other.  They are the following:

  • The RTI Electrical that is associated with insulating properties.
  • The RTI Mechanical Impact which is related to the impact resistance, toughness, elongation and flexibility.
  • And, the RTI Mechanical Strength that is associated with the mechanical properties or the structural integrity of the plastics.

 

Continuous Use Temperature Values for Common Polymers

 

Polymer Name Min Value (o C) Max Value (o C)
ABS – Acrylonitrile butadiene styrene -20 80
PA – Nylon Polyamide, 66 30% Glass Fiber 100 150
PAI – Polyamide-Imides (TORLON) -196 220-280
PBI – Polybenzimidazole (CELAZOLE) 204 540
PC – Polycarbonate, high heat 100 140
PE – Polyethylene, 30% glass fiber 100 130
PEEK – Polyetheretherketone 154 260
PEI – Polyetherimide (ULTEM) 170 170
PP – Polypropylene 100 130
PS – Polystyrene, high heat 75 90
PSU – Polysulfone 150 180
PTFE – Polytetrafluorethylene – 260
PVC – Polyvinyl chloride, rigid 50 80
PVDF – Polyvinylidene fluoride (KYNAR) – 149

 

Continuous use Temperature Does Not Define Polymer Strength

 

It is important to note that the continuous use temperature does not define a part’s ability to handle a load under a specific temperature. One material that proves this is PTFE. PTFE is an advanced thermoplastic that can handle 500 o F continuous service without breakdown. Yet, it is a soft material, which bends easily at room temperature. This property is called the heat deflection temperature (HDT), which is another important property to consider.

 

AIP: Unrivaled Precision Machining

 

Data charts can give you the Continuous Use Temperature, glass transition and other values. However, a chart can give a general idea of these values, but an entire data set with the curve of a material is the best way to determine the right material for your project.

 

Be sure to work with a plastics machining company that can provide you a wide range of data on the CUT of polymers and composites. Your sales engineer will be able to give you a detailed response on how the continuous use temperature will affect your project’s design and functionality. Talk to one our engineers at AIP about your project design, and we will work with you to provide unrivaled expertise from your project’s initial concept to completion.

 

Supportive Information

 

Certifications and Regulatory Resources

 

Our team is dedicated to providing unparalleled, quality machined polymers and composites. Learn more about the material properties we consider when working on a project.

 

Read our blog on Moisture Absorption
 

 

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How Moisture Absorption Relates to the Stability of a Machined Polymer

April 13, 2021

Most polymers have a natural tendency to absorb water. In fact, some superabsorbent polymers are highly sought after in advanced applications for medical, construction and more. Yet, moisture absorption of thermoplastics leads to changes with regard to processing and properties.

 

It is crucial for machinists and designers to understand the moisture absorption of thermoplastics for CNC machining. During the design phase, this not only helps with initial material selection, but plays a role in predicting the life span of a part. At AIP, we take great care in providing unrivaled results to ensure the optimal dimensions and properties for machined polymers and composites. Join us in this technical brief as we give an in-depth explanation of the effects of moisture absorption for machined polymers.

 

Plastics Machining and the Importance of Water Absorption

 

Moisture / water absorption is the capacity of a plastic or a polymer to absorb moisture from its environment. Absorbed moisture sometimes acts as a plasticizer, reducing the glass transition temperature and strength of plastic (this is a reversible side effect). However, absorbed water also can lead to irreversible degradation of the polymer structure.

 

Some effects include:

  • Dimensional and mass changes (swelling) caused by water absorption
  • Extraction of water-soluble components
  • Changes in mechanical (elasticity, tensile strength, impact strength) and electrical performance

 

Water absorption is expressed as increase in weight percent or % weight gain of a plastic specimen under the following testing procedures:

  • Water Absorption 24 hrs at 23°C – Immersion of a plastic specimen in distilled water during 24 hours at 23°C
  • Water Absorption 24 hrs at 100°C– Immersion of a plastic specimen in distilled boiling water during 24 hours Water Absorption at saturation – Immersion of a plastic specimen in distilled water at 23°C.  Measurement occurs when the polymer does not absorb water anymore
  • Water Absorption at Equilibrium– Plastic specimen is exposed to a humid environment — generally at 50% relative humidity — at a specified temperature — 23°C or 73.4°F — for 24 hours

 

(Source: Omnexus)

 

Exposure to humidity, immersion and boiling water can result in different material responses. The equilibrium moisture content can be used to compare the amount of water absorbed by different types of plastics when they are exposed to moisture.

 

Plastics Processing and Properties

 

Polymers are affected by moisture from their environment or from simply sitting on a shelf waiting to be used.  This is not a huge concern, but when the moisture absorption reaches more than 1% or 2%+, this can result in enough dimensional movement to create concerns.

 

Moisture Absorption Affects:

  • Mechanical properties
  • Wear properties
  • Dimensions

 

For example, parts made from TORLON (PAI) require special attention due to a 1.7% moisture at saturation value.  While this number may not sound like much, it is enough to cause a precision machined TORLON part to exceed tolerance; in this scenario, the part cannot be used.

 

Therefore, it is important to properly package these mission critical polymers for lasting shelf-life and function.  This can be achieved in two ways:  1) Vacuum-sealing them in a moisture-impermeable layer or 2) packaging them with bags of desiccant.  This prevents moisture uptake in humid environments.

 

Tests to Measure Water Absorption of Plastics

 

Source

 

ASTM D570 – Standard Test Method for Water Absorption of Plastics

 

This test method for rate of water absorption has two main functions:

  1. A guide to the proportion of water absorbed by a material and consequently, in those cases where the relationships between moisture and electrical or mechanical properties, dimensions, or appearance have been determined, as a guide to the effects of exposure to water or humid conditions on such properties.
  2. A control test on the uniformity of a product. It is particularly applicable to sheet, rod, and tube arms when the test is made on the finished product.

 

Procedure:  Parts are dried in an oven for a specified time and temperature and then placed in a desiccator to cool.  Upon cooling, the specimens are weighed to establish a point of reference.  The material is then submerged in water at standardized conditions (usually 23°C for 24 hours or until equilibrium).  Specimens are removed from the liquid, dried and weighed.

 

What affects water absorption?

  • Type of plastic
  • Morphology (crystalline, amorphous…)
  • Type and proportion of additives, fillers and reinforcements used
  • Fiber fraction and orientation (in composites)
  • Relative humidity and temperature
  • Length of exposure

 

Water Absorption Values for Common Polymers

 

Polymer Name Min Value (% weight) Max Value (% weight)
ABS – Acrylonitrile butadiene styrene 0.05 1.80
PA – Nylon Polyamide, 66 30% Glass Fiber 0.80 1.10
PAI – Polyamide-Imides (TORLON) 0.10 0.30
PBI – Polybenzimidazole (CELAZOLE) 0.4 5
PC – Polycarbonate, high heat 0.10 0.20
PE – Polyethylene, 30% glass fiber 0.02 0.06
PEEK – Polyetheretherketone 0.10 0.50
PEI – Polyetherimide (ULTEM) 0.20 0.30
PP – Polypropylene 0.01 0.10
PS – Polystyrene, high heat 0.01 0.07
PSU – Polysulfone 0.20 0.80
PTFE – Polytetrafluorethylene 0.005 0.015
PVC – Polyvinyl chloride, rigid 0.04 0.40
PVDF – Polyvinylidene fluoride (KYNAR) 0.03 0.05

 

As the chart notes, some polymers such as Nylon (PA) have a higher rate of % gain from moisture absorption.  However, polymers like PVDF and PTFE have a very low % gain in weight after the ASTM D570 test – which makes them excellent candidates for applications where moisture is a factor.

 

Performance thermoplastics are often exposed to high temperature applications (aircraft engines) which also absorb high levels of moisture.  This is common in materials such as PBI (Celazole) and PAI (Torlon), since these polymers absorb moisture at high rates but are also specified in high temperature applications.

 

Basically, what can happen is that these materials absorb the moisture if not properly stored and packaged.  Then if subject to high levels of heat without time for the moisture to dissipate, the internal moisture boils and turns to steam causing the parts to crack and blister.

 

Managing Moisture Absorption

For predictable machined part fit and performance, stock shapes and finished parts should be stored in a dry environment.  Both finished parts and stock shapes should be packed in moisture barrier packaging.  Only open packaging just prior to use.  In the event that a part may have adsorbed so much moisture as to risk shocking it when placing it in high temperature or vacuum service, consider drying the material prior to use or re-use.

 

Your machining facility will have specifications on temperature and storage procedures for all polymers, stock shapes and components.  When it comes to critical applications, work with a machine shop that has high standards for storing products.  After all, machining a polymer is only part of the entire process; wasted machining, revenue and parts is not worth risking poor storage conditions.  The table below shows some common packaging for polymers to increase and preserve shelf-life.

 

 

Generally, you can find a polymer’s 24 Hour and Saturation Moisture Absorption Values on a data chart.  A chart can give a general idea of the moisture absorption, but an entire data set with the curve of a material is the best way to determine the right material for your project.  Be sure to work with a plastics machining company that can provide you a wide range of data on the moisture absorption of polymers and composites.  Your machinist will be able to identify how moisture and humidity will affect your project’s design and functionality.  Talk to one our engineers at AIP about your project design, and we will work with you to provide unrivaled expertise from your project’s initial concept to completion.

 

Supporting Materials

Certifications and Regulatory Resources

 

Want to learn more about factors that contribute to effective CNC machining?

Read Our Blog on CLTE
 

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