Ultrasonic Plastics Welding

Midwest Engineered Systems can automate plastic welding processes in any situation. From small stand-alone systems to large robotic integrated processes, MWES custom designs each plastic welding system for your specialized process needs. Backed by extensive knowledge, experience and certifications, our expert professionals are able to deliver specialized service whether you need a custom fabricated plastic part or an onsite repair of your current plastic welding system. Automated plastic welding systems are offered in a variety of capability ranges depending on your plastic welding needs, whether the parts are simple, or have complex geometries.

Welding with ultrasound is a process of combining thermoplastics or metals using the heat created through mechanical actions that operate at a high frequency. Electrical energy with high frequency is produced and is converted into this high-frequency mechanical motion. The applied force is used in conjunction with a mechanical motion to produce heat friction at the mating surfaces or joint areas of the metals or thermoplastics. This heat friction causes the parts to melt together, forming a molecular bond that is strengthened once the materials cool back down. In the case of metals, the heat friction raises the metal surfaces’ temperatures to around one-third of their melting point. Rather than melting the metals, the heat friction removes films and metal oxides from the metal surfaces, permitting the metal atoms to move between the surfaces and fuse the metals together.

The benefits of ultrasonic welding are that they produce lower production costs, they create a very effective bond with a high-quality seal that doesn’t require fillers, and they have faster welding times than most other traditional welding procedures.

Plastic Welding

Plastic welding is a type of welding that forms a fusion of two thermoplastics that are compatible with each other. Welding plastics works the same in principle as welding metals ordinarily. The process involves bringing two plastic areas or surfaces to their melting points and then applying force to combine the plastics. The welding process can be supplemented with a plastic filler rod that is similar to the plastics being welded together.

The benefits of welding plastics include their versatility and durability. Welding jobs for plastics can lead to the creation of small, intricate parts, or they could lead to fairly large plastic tanks designed for chemical storage. Compared to welding metals, welded plastics have lower manufacturing costs, are more resistant to corrosion and are easier to transport.

Pendulum Welding

Pendulum welding is the best choice for short weld runs and is useful when mating surfaces are in difficult to reach positions. The method gets its name from the pendulum motion that is employed to evenly heat both the welding rod and the parent plastic material. One advantage of pendulum welding is that the operator can monitor the material’s flow during the welding process and which results in a more precise weld seam.

Good Pendulum welding requires three elements; proper temperature, continuous welding speed, and evenly distributed pressure on the welding rod. All of these elements together result in a foam wash on the edges of the weld which means that the weld seam has good penetration and strength. The weld should have time to cool off before any trimming or cleaning is done to ensure the weld reaches its full strength potential.

Speed Welding

Speed welding is most effectively used on long weld runs. It gets its name from the fact that it’s a generally faster process as compared to the pendulum technique. The speed weld process is most suitable for joining plastics together in tight corners. Speed welding is similar to a soldering iron in appearance and wattage, the only difference is that speed welding is fitted with a feed tube for the plastic weld rod.