May 12, 2026

Even though we consider trackers as GPS devices, trackers are nodes that collect location, environmental and behavior data. As such, trackers have implemented communication modules on PCBAs for collecting data. The data itself should be transmitted via cellular networks using specific standards and protocols. A key constraint to consider is battery life, which is typically defined before a tracker project is started.

Often trackers use ultrasonic welding to connect or bond plastic materials that are placed in fixtures. For this to work, vibration that uses specific frequencies, pressure and heat are utilized to create a solid material at the end of the ultrasonic welding process.

Ultrasonic welding also has a significant influence on the housing of devices  and various parameters have an influence on final look of device. Engineers need to be aware of the potential for ultrasonic welding to create deviations from the original specification or to create issues that can result in other negative feedback.

Challenges with ultrasonic welding during production

During assembly of devices, using ultrasonic welding can cause issues and challenges that must be overcome.
Those issues are usually:

• Air tightness failure
• Structural part fracture
• Step difference
• Plastic overflow
• Rubber melted during assembly

Improvements of ultrasonic welding during production

Air tightness failures happen because of improper design of housing joints, if the structural dimensions of an ultrasonic welding line are too small, resulting in insufficient volumes of molten material to create a strong enough bond. Also, excessive use of heat, pressure or vibration in welding zones can result in generation of bubbles during welding or rupture of materials during ultrasonic welding.

When it comes to fractures in structural parts during ultrasonic welding, causes can involve welding time that is too long, prolonged vibration of the material or because the melt index of material is at a critical point. In addition, the structure of the can be affected where it contacts the welding horn and is subjected to synchronous vibration.

Deformation of the housing can result from several types of failures including welding pressure, excessive welding strokes, insufficient design strength or bad design of the fixtures. Plastic overflow issues happen in situations when welding pressure or amplitude causes melting of material or squeezing. Sometimes just the speed of welding leads to uncontrolled material flow. Further issues are caused by sub-optimal design of the upper and lower part of housing, poor joint design or bad surface connections.

Rubber melting issues can also occur when there are melting or movable materials on the surface of the housing. Due to the conjunction of two materials and deformation caused by inconsistent vibration frequencies, high temperatures cause deformation of rubber.

Proven fixes

Solutions for airtightness fail often so improved design and updates of fixtures, with a focus on molding quality, is necessary. Also, material pretreatment is often very useful for reduction of failures. Optimization of design parameters used for ultrasonic welding are very important. Predefining the thickness of material and ribs in area of ultrasonic welding is essential due to deviations that can occur.

For the structural parts, solutions are often advising caution regarding the melting index, redesigning of the housing to increase impact force resistance and reduction of welding time and vibrations. For housings with welding horns, thin ribs or sharp corners should be avoided as much as possible.

To avoid housing deformation, the focus should be on the base fixture design, and this should be updated with the supplier. Molding dimensions must be monitored in the molding factory to ensure optimization of design and decreasing the welding stoke and pressure.

Plastic overflow is an issue that has been resolved using different setups of ultrasonic welding stations. With a change of settings, most of the issues can be resolved, but sometimes update of the design is needed.

For rubber issues, the most common solution is usage of more flexible materials with greater movable clearance, so that there are no large deviations.

How Ikotek solves the ultrasonic welding challenge

As a big challenge during production, ultrasonic welding must be done in a way that assures final product quality, and all issues must be overcome before setup of MP.

Due to Ikotek’s large and in-depth knowledge base, it is much easier for us to resolve all the issues.

Often, some solutions can be taken over so that on the production line small changes are made.

Restoring throughput through thermal design

Ultrasonic welding is essential for reliable operations in real world conditions. By optimizing ultrasonic welding, improving the design of housings and reducing potential pain points, it is possible to eliminate all the issues and challenges that can occur.

For more insights into tracker design, explore these resources:

Blog: https://www.ikotek.com/blog/ikotek-clinic-how-to-dimension-iot-trackers-based-on-use-cases/
Contact: www.ikotek.com/contact