Plastic Welding

What is plastic welding?

Plastic welding is the process of heating two pieces of plastic and pressing them together until they fuse. There are several different types of plastic welding. Each technology differs in how they apply heat and pressure to the parts, but the basic steps are the same — add heat, apply pressure, and cool. Plastic welds are strong molecular bonds. Depending on which welding technology is used, the weld is hermetically sealed.

Download our Plastic Welding Decision Matrix

Choosing an assembly technology can be challenging.
Use this decision matrix to discover which plastic welding and staking processes may be options for your application.

Hot-Plate Welding

Hot-plate welding is the process of welding two plastic parts together using a heated tooling plate. A weld rib or bead on each component is brought into contact with the hot plate. Heat conducts into the weld rib causing it to melt. The heated tool is then removed and the parts are pushed together until they bond to one another.

Technology Examples:

  • Rapid Conductor
  • Compact FUSION

IR Welding

IR welding is the non-contact welding process that joins two plastic parts together with IR energy. IR emitters heat a weld rib or bead on each component. The IR source is removed and the parts are pushed together until they are welded.

Technology Examples:

  • InfraGuide
  • Quartz IR
  • Metal Foil IR

Laser Plastic Welding

Laser welding uses a precise IR laser beam that is directed through a transmissive material and penetrated into an absorptive material. The two materials are held in tight contact with each other and the joint between them heats up and melts as energy from the laser is absorbed. The result is a clean weld with minimal flash.

Technology Examples:

  • Extol configures laser welding machines around the application

Staking

Plastic staking is a method of joining components together using a molded stud or boss to mechanically retain a mating component. Heat is applied to the boss, softening it, and a forming tool is used to reshape the material into a cap or stake.

Technology Examples:

  • nanoSTAKE
  • InfraStake
  • Ultrasonic Staking
  • Hot-Air Staking

Spin Welding

Spin welding is a method of joining plastic components together with surface friction concentrated in a circular weld joint. One part is spun relative to another and force is applied, causing the material to heat and melt. The spinning process stops and the parts continue to be pressed together while they bond together.

Technology Example:

  • Vortex PRECEDENCE

Through-Transmission IR Welding

Innovative through-transmission infrared welding in a compact package. This technology uses focused IR light energy to replace adhesives. Useful in both linear and spot welding applications.

Technology Examples:

  • InfraWeld

Hybrid Vibration Welding

Two components are vibrated in shear against each other, generating heat from friction. Vibration stops and pressure is maintained while the components bond to one another. Hybrid vibration welding adds an IR preheat at the beginning of the cycle to soften the rib and reduce the amount of particulate flash generated from the vibration cycle.

Technology Examples:

  • CEMAS Vibration Welders

Ultrasonic Welding

Ultrasonic welding uses high-frequency vibration to melt and weld plastic. A tool vibrates at ultrasonic frequencies and causes concentrated molecular vibration in the weld joint. The friction between the molecules heats and melts the plastic. Once the vibration is stopped, the tool maintains a holding pressure on the joint to create a bond.

Technology Examples:

  • Dukane Ultrasonics
  • Branson Ultrasonics
  • Herrmann Ultrasonics

Blog posts about plastic welding and plastic staking

Plastic Joining: Make or Break Factors

Plastic Joining: Make or Break Factors

“What technology should I use to join my application?” is one of the most common questions we get from customers looking to ensure the best performance and durability for their project. Unfortunately, there’s no one-size-fits-all answer to that question. Several factors go into whether or not an application is compatible with different plastic welding technologies, and understanding them is key to making an informed decision.

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How to Get Started with Laser Plastic Welding

How to Get Started with Laser Plastic Welding

Plastic part manufacturers increasingly turn to the power of laser plastic welding to assemble their parts. This cutting-edge technology offers several advantages, including fast, precise, clean welding that produces robust, airtight parts. It’s no wonder that many professionals are eager to learn how to use this technique. This guide is designed to provide you with all the tools you need to take your plastic welding skills to the next level and revolutionize your manufacturing process.

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Designing for Strength: What to Consider in Plastic Part Design

Designing for Strength: What to Consider in Plastic Part Design

One of the more difficult questions I get asked by our customers is how to optimize assemblies for strength. This is an incredibly complex question but an important one when it comes to product development. Simulations like Finite Element Analysis are always a helpful tool, but FEA only provides some of the information, not all of it. Here are some questions to begin with during the development process

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When to use hot-plate welding

When to use hot-plate welding

When considering the common plastics joining methods for assembling a new product, in the mix of options should be hot-plate welding. This low-force method of heating and bonding plastic parts has been around a long time. Contemporary machinery and tooling provide users with exceptional control and consistent weld results.

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Why is my plastic sticking during the staking process?

Why is my plastic sticking during the staking process?

This question has been posed to me by many customers. I hear statements like, “The machine works great for a long time, and then we suddenly get all of this sticking and stringing.” This issue is somewhat common in most types of staking technologies and varies in severity among different thermoplastic materials.

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Ultrasonic or Hot-Plate Welding? The Battle for Superiority in Medical Device Assembly

Ultrasonic or Hot-Plate Welding? The Battle for Superiority in Medical Device Assembly

Welcome to our exploration into plastic welding for life science applications. As we embark on this journey, imagine yourself as a master chef, adeptly balancing the strengths and potential weaknesses – such as leak rate – of ultrasonic welding (USW) and hot-plate welding (HPW), much like harmonizing flavors in a gourmet dish. Each method brings unique strengths and challenges to the table, contributing to the final product’s quality. So, let’s dive into this adventure where strength and leak rate take center stage in the intricate world of plastic welding for life science applications.

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