Advances in Material for Injection Molding Medical Device Components

Plastic suppliers have been increasingly responding to the needs of medical device manufacturers’ requirements of lightweight, aesthetically pleasing, but strong materials for their devices and components.  They are responding to the movement toward smaller products and handheld devices.     As well as, addressing the problem of breaking down from the chemicals and cleaners used to disinfect them. 

Polycarbonate Various Grades and Fillers

Polycarbonate is impact resistant, clear, high heat resistance resin. This resin has dimensional stability, is resistant to UV light, and has flame retardant properties.  Gamma and EtO sterilization can be done.  Ultra sonic welding can be used with this material.  Typical applications include reservoirs, artery cannulas, high-pressure syringes, stopcocks, centrifugal force separators, lures, blood filter housings and dialyzer housings such as glucose meters, pumps, insulin pens, surgical device handles and housings.

Glass filled polycarbonates are increasingly being used in the design and manufacturing of medical devices and equipment housings. These glass filled blends provide structural support, durability and compatibility with several devices because they have the same structural support of traditional materials like metal.   However, the parts can be made smaller and thinner reducing the weight of the part and providing ease of use.    These resins are injection molded into handheld surgical instruments to diabetic monitors to insulin pens where stiffness, design flexibility and aesthetically pleasing appearance are required.  These resins are available with different amounts of filler and used in a variety of applications.  The intended function will determine the amount of glass filler used and outside factors like pressure or force that will be exerted on the product, the environment in which the product will be used and the desired life of the part or device. 

Makrolon Polycarbonate resin is lightweight and has glass-like transparency.  Medical grades can be sterilized using steam, gamma or ethylene oxide methods.  This material has an unusual combination of strength, rigidity and toughness that helps prevent potentially life-threatening material failures. It has excellent heat resistance with a glass transition temperature.  It provides glasslike clarity, a critical characteristic for clinical and diagnostic settings were visibility of tissues, blood and other fluids are required. 

Read More

Robotics and Automation for Plastic Injection Molding

When it comes to custom injection molding, the implementation of robots and automation processes have proven to;

  • Increase throughput
  • Reduce cycle times
  • Reduce scrap
  • Improve both part quality and total savings in general

Although an upfront investment in automation is often required, the advantages have proven to be worth the investment.   Automation can be used during the injection process to remove parts from the molds, placing inserts or metal components into a molding machine for the insert or over molding process.  They are used in the secondary operations for assembly, packaging, part-trimming, de-gating, drilling and sorting.

Understanding the Use of Robots in Custom Injection Molding

It is virtually impossible to ignore the reality that robotic automation is changing the face of custom injection molding.  

Robots and robotics are programmed to carry out specific repetitive actions without variation.   These actions are predictable due to programmed routines that specify the direction, deceleration, acceleration, velocity and distances.  Robots perform these actions with profoundly successful levels of accuracy. 

Often robotic operations will use precise guidance and have the ability to adapt to different part-types using intelligence-based features.  These features include; vision, integrated force and sensing capabilities

Read More

5 Things You Need to Get the Most Accurate and Timely Injection Molding Quote

If you are planning a plastic injection molding project, and want to ensure excellence and timelines in your product delivery - review these following five considerations to make certain the result is exactly what you need.

1) Do 2d part drawings and 3d cad models exist?

The first question to ask yourself is this; Are you replacing an existing or similar product? Which means there may already be 2d drawings and cad models to work from.

If you do not have 2d part drawings or 3d cad models of the part, these should be provided. The 2d part drawings and 3d cad models provide detailed information on the size and complexity of the part.  

This is really necessary because words can always be interpreted differently, and details can be missed. This could make for significant differences in mold design, as well as cost. 

When done in this way - you can give the plastic injection molder the ability to access the part from a mold design perspective, to define parting lines, and draft angles for proper ejection and gate locations. This will protect and maintain the manufacturability of your parts.

2) What is the application for your product and its material?

It is important for your injection molder to know the end application, and usage conditions.  These include variables such as temperature, chemical contact and resistance. It also includes; 

  • Applied stresses during use 
  • Transparency/opacity 
  • Color, aesthetics
  • Water absorption
  • Lubricity and wear resistance

Your injection molder can then help to recommend a material base properly suited for your application. This is important for the plastic injection mold design stage because different resins have different shrinkage rates, levels of corrosiveness, etc. It is not practical to change resins after the mold has been fabricated.  

This also relates to the type of manufacturing environment required to manufacture the product, for example a clean room may be required. 

Read More

3 Must Ask Questions Before Choosing an Injection Molder

When choosing an injection molder for manufacturing of plastic medical devices or other specialty projects, there are mandatory guidelines that should be used to determine how to choose the right company.

1) What Quality Management System/Quality Standards do they Follow?

It is critically important to assure there is a robust Quality Control system in place. This shows that the company monitors the effectiveness of their supply chain and demonstrates traceability related to regulations of materials and finished goods.   Correct documentation, data monitoring and storage is critical to any quality injection molding manufacturing process. 

To this end, some things to remember include:

Asking your injection molder what quality management certifications they have and if that meets your requirements. For instance; FDA registration, or ISO 13485:2003 are common requirements for medical devices and components.

If these systems are in place they require a certain amount of documentation, assessing and minimizing of risks, as well as product realization.  

These types of quality certifications also show that this injection molder takes their business seriously, which means they have higher-than-average quality standards.

 2) Can They Support your Entire Product Life Cycle?

This means can they offer you a single source for procurement? This requires having a company that can provide services from the design phase through production - then have it immediately shipped out the door from the factory. 

Will they provide design and development services either as your design team - or enhance your in-house staff. They offer insight and recommendations based on their own experience, they know the industry best practices, and then look at design for manufacturability. 

Read More

How Resins Become Plastic Components or Devices for the Medical Industry

Parts made by injection molding are widely used in the medical and pharmaceutical industry. Some of the many varieties of plastic injection molded parts include;

Read More