Plastic Extrusion: The Five Elements of Quality Control

Posted on: September 9, 2021

Thermoplastic extrusion is often an ideal solution for customized parts. Whether it’s for window exteriors or automotive parts, you need to have confidence in the end-to-end process in order to provide value to your products and customers.

As widely adopted as plastic extrusion is, it’s important that manufacturers understand how to evaluate the quality control protocols of your thermoplastics partner. How can you verify the entire end-to-end process to protect the value for your end users and consumers? 

One: Start with the Right Product Specs

When you’re developing a new product, or a custom part, you need to work with specialized engineers and testers during the prototyping process. In addition to the right dimensional data, work with your extrusion partner to verify that your plans and prototypes will result in high-quality parts and mating parts. 

Seasoned thermoplastic extrusion providers should have a range of expertise in-house that represents generations’ worth of trade experience. The manufacturing process is complex, and you need to work with a team that is aware of how tolerances and other material properties will impact the final product. 

Two: Seek Out a Thermoplastic Extrusion Material Expert

Seasoned engineers and trades experts have the material knowledge necessary to select the right composition for your application. For example, advising on which materials (or combination of materials) are FDA compliant is critical for food-grade packaging. If your part has both rigid and flexible elements, that will impact the overall part composition and the material makeup.  

Other characteristics to consider include:

  • UV resistance
  • Different additives for parts that require flexibility 
  • Color temperature and color matching
  • Stabilizers for compound
  • Product function impacts on material requirements 
  • Safety regulations (flame retardants, stabilizers)

Your extrusion partner should also have adequate facilities on-site to test the final product under different conditions. The right tests will indicate how those materials will perform under different temperature extremes, for example. Lastly, a well-sourced plastic extrusions manufacturer ideally should have enough available materials on hand. With an adequate inventory, the design team should then be able to advise on dynamic and creative options to keep the job on time while satisfying quality demands. 

Three: Advising and Planning the Right Process 

There is, as we’ve mentioned, a lot of complexity that goes into designing, prototyping, machining, and finishing plastic extruded parts. If a part requires multiple materials, that will impact the overall timeline. 

In-house tooling experts will be able to provide a realistic schedule for parts that require custom tooling vs. existing tooling solutions. That in-house expertise also reduces the need for additional outsourcing (avoiding further cost and schedule issues). If an innovative solution is required, you need confidence that you’re working with a team that’s able to execute customized tooling and machining under tight deadlines. For example, the professionals at Custom Profiles understand the end-to-end process that will ensure quality retention while also matching the level of output you need. 

Finishing steps can add time to the job schedule. Our team provides this value-added service to accommodate and streamline your production schedule without adding another vendor into the already-complex development cycle. Those additional vendors can also result in added costs for shipping and longer lead times. Lastly, planning for shipping cycles helps your product teams anticipate a predictable delivery schedule when your parts go out the door. 

Four: Seamless, Streamlined, On-Time Execution

Before those products go out the door, your extrusion partner needs to have a verifiable and well-documented assessment process for the product while it’s being built and after it’s completed. Each quality assurance process typically includes a set of quality metrics that ensures consistency, safety, and reliability. 

  • Visual check: Visual inspections look for obvious visual defects and confirm color saturating and quality, as well as finish quality.
  • Dimensional verification: This means testing and measuring wall thickness, sizes and locations of holes, curvature, length, width, joints/ends, etc. It also involves further verifying that those dimensions satisfy standard tolerances in highly regulated industries, including automotive, aerospace, medical, pharmaceutical, food, construction, etc.
  • Weight and density: Includes ensuring that weights do not exceed industry limits while also verifying standardization and repeatability for reusable and reliable parts.
  • Performance and workability testing: This includes verifying that plastic extruded parts satisfy additional product requirements. Examples include testing them with mating parts or evaluating whether they are ready for secondary processing or additional fabrication. The extruded parts may also require testing for resistance to specific chemical compounds. Other performance testing metrics include:
    • Flammability 
    • Hardness 
    • Weather resistance (fading, water resistance, etc.) 
    • Abrasion 
  • Final acceptance review: The engineering and product team completes a final testing and inspection process prior to releasing or shipping, including verifying that the part is compliant.

Five: Valuing and Prioritizing Long-Term Relationships

While relationships can often seem intangible, they may be one of the most important elements of the quality process. Working with a plastic extrusion partner that prioritizes your long-term relationship is a critical element in maintaining the quality of your products. The market may shift, and the demands for your products right along with it. When those shifts happen, it’s important that you have a partner in your corner who understands your business and can help you incorporate continuous improvement into your entire workflow. 

Custom Profiles has an established history as a partner dedicated to exceeding our customers’ expectations and delivering cutting-edge and cost-effective outcomes. We also have a track record of satisfying delivery schedules, even when the supply chain is challenged by material shortages.

If you’re seeking advice and consultation for your plastic extruded parts, contact one of our qualified engineers today

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