With the rise of Electric Vehicles and more demanding fuel efficiency regulation being mandated, is metal becoming a thing of the past?

Plastic is increasingly being used in place of metal for many different purposes. Specifically, plastic clips are replacing metal brackets used on automotive fluid routing assemblies as mounting supports for HVAC and brake lines. Plastic clips are perfect alternatives in these automotive applications and many more.

Why are manufacturers looking to convert more brackets to plastic?

  • Plastics cost less than metal and less costly to manufacture
  • Ability to manufacture more complex designs
  • Weight reduction

Plastic clips have multiple benefits. In the following, we discuss the top advantages of replacing metal brackets with plastic clips.

Plastic Clips Cost Less

There are a variety of reasons that factor into why plastic fastening devices cost less than their metal counterparts.  A few of the major factors include:

Material

Because plastic is lighter weight compared to steel, injection molded clips will cost less as heavier weights typically equal greater costs.

Labor

Compared to most metal brackets, the process of injection molding clips is typically way less labor intensive.  Metal fabrication will most likely include a variety of additional steps, including: cutting, bending, welding, metal finishing prep, coating.  Each of those steps can add significant costs to the project.

Tooling

Tooling for metal stamping and forming has a much higher cost than tooling for plastic. The tools needed for plastic can cost up to 50% less, a huge reduction in cost.

The tools for metal also wear more rapidly and need to be replaced more often than the tools for plastic, creating even more additional costs.

Shipping

A commonly overlooked factor towards the overall cost of a metal bracket compared to its plastic counterpart is shipping & handling.

When transporting metals, protective shipping products must be used in order to prevent damage, unlike most plastic clips, which don’t need much protection during shipment.

A more important factor going towards shipping is that plastic weighs way less than steel brackets, which we’ll explore in this next section.

Lightweighting

If you were to compare a part made of steel to the exact same part made from thermoplastic, the plastic version could be up to more than 6 times lighter! Design changes will most like need to be made in order to successfully replace a metal bracket with a plastic clip, but most likely, there will be a significant weight reduction.

For example, most automotive line clips you’ll find are made from Nylon 6/6.  Nylon 6/6 typically has a  density of 1.14g/cm3. Compare that to steel, which typically has a density of around 7.85g/cm3.

So, with lightweighting being an automotive megatrend that has become incredibly important for OEMs as new fuel efficiency regulations are mandated, it’s time to explore thermoplastic alternatives in order to improve a vehicle’s efficiency and performance.

Plastic Clips are Non-Corrosive

Another element that can easily get overlooked is that metal brackets are more at risk for corrosion issues.  This corrosion weakens the metals over time, causing them to be damaged, resulting in potential liability issues.  Plastics, on the other hand, won’t corrode and are less likely to suffer from a chemical exposure.

A common issue that has to be addressed with automotive HVAC lines is preventing galvanic corrosion. Galvanic corrosion is an electrochemical process in which one metal corrodes preferentially when it is in electrical contact with another, in the presence of an electrolyte.  In order to combat that with metal brackets, the tier-two bracket manufacturer or tier-one HVAC line manufacturer must also source a non-conductive EPDM grommet, which is an unwanted additional cost.

By converting to plastic, automotive manufacturers are able to avoid this issue completely with the correct clip.

Plastic’s Versatility

Plastic is an extremely versatile material, unlike metal. Plastic clips can be made into complex shapes and in a variety of different colors straight from the start. This makes them basically ready to go right out of the tool.

Unlike plastic, metal almost always has to go through several secondary processes before it is ready for installation. Metal brackets usually have to be cut or stamped, drilled, formed, pre-treated/cleaned, coated to prevent rust, packaged appropriately, etc.

Metal may also need multiple components added or installed such as a fastener or an isolator. With plastic, all of those can be built in, eliminating the need of multiple parts.

How to Make the Conversion from Metal Brackets to Plastic Clips

If you’re currently exploring the option of converting to plastic, you’ll want to make sure you work with  a partner that has experience across the product design, tool design, validation, fulfillment spectrum, and will:

  • Design from scratch to meet your needs or work with an existing design and suggest changes to ensure all specifications are met
  • Take the time to understand the assembly parameters and is able to design and perform comprehensive test plans to match real world applications
  • Use FEA software to optimize the clip’s mechanical properties and eliminate potential failure points
  • Use mold flow analysis and tool design improve product performance and meet tight tolerances

About Ammex Plastics and Echo Engineering

Ammex Plastics and Echo Engineering have been investing heavily with the automotive fastening market by developing a library of different designs, hiring plastics and process engineers, adding additional presses, and purchasing new testing and measuring devices.

We are experienced in designing and manufacturing a variety of different automotive clips used on HVAC lines, brake lines, harnesses, etc.

Thinking of making the switch from metal to plastic? If you are or if you have any other questions, visit our Contact page and send us a message! We have a team of technical experts ready to find the best solution for you.

 

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