What is ultrasonic welding
La ultrasonic welding is a thermoplastic joining technology using high-frequency mechanical vibrations (among 20 and 40 kHz) to melt plastic materials quickly, cleanly and precisely. Thanks to the absence of glues, solvents or fasteners, it is a solution environmentally friendly, safe and repeatable. In the sector automotiveis applied in numerous assembly processes, contributing to the lightness, robustness and reliability of modern vehicles.
Sonomax Srl, an Italian company with over twenty years of experience in the design and production of ultrasonic weldersoffers tailor-made solutions for the integration of this technology into the production processes of Tier 1 and Tier 2 manufacturers and suppliers.
How the ultrasonic welding process works
The process takes place through a system consisting of:
- Electronic generatorwhich produces the high-frequency signal.
- Piezoelectric transducerwhich converts the signal into mechanical vibrations.
- Boosterwhich regulates and amplifies the vibration amplitude.
- Sonotrode, the element that comes into contact with the parts to be welded, transmitting the ultrasonic energy.
The sonotrode exerts a controlled pressure on the components to be joined. The vibrations generated by internal friction between the contacting surfaces, they localise heat and melt the material in the joint area. Once the ultrasound emission is finished, the pressure is maintained for a few moments to allow the solidification of the joint.
The result is a strong and visually discreet weldingobtained in a few tenths of a second.
Advantages over other joining methods
Compared to other techniques such as bonding, heat welding, interlocking or mechanical fastening, ultrasonic welding offers numerous advantages:
- Very fast cycle times
- No consumables (adhesives, screws, rivets)
- Clean joints
- Reduced energy consumption
- Highly automatable process
- Repeatability and total electronic control
- Environmental compatibilitywithout harmful emissions
In the automotive sector, where production volumes are high and quality is imperative, these advantages make ultrasonic welding a strategic technology.
Industrial applications in the automotive sector
Ultrasonic welders find application in a wide range of vehicle components:
- Internal Componentsdoor panels, dashboards, air vents, glove compartments, loudspeaker grills.
- Electronic elements: control units, sensor housings, wireless charging modules.
- Lightsdiffusers, shells, polycarbonate and polystyrene reflectors.
- Driver Assistance Systems (ADAS)radar housings and sealed cameras.
- Wiring and batteriesWelding of plastic tabs and terminals.
- Interior cladding and acousticsapplication of textile and sound-absorbing materials.
La flexibility of technology allows complex geometries, combined materials and tight tolerances to be addressed, while ensuring mechanical tightness and aesthetic quality.
Technical requirements: frequencies, powers and materials
Sonomax welding machines can be configured according to customer requirements, taking the following parameters into account:
Operating frequencies
- 20 kHzfor large workpieces or thick walls.
- 30-35 kHzfor medium components.
- 40 kHzfor small components or delicate materials.
Available powers
- From 400 W to 3000 Wdepending on the welding area and the desired strength.
Compatible materials
Sonomax machines are optimised for welding:
- Polycarbonate (PC)
- Polyethylene (PE)
- Polypropylene (PP)
- Nylon (PA)
- ABS
- Polystyrene (PS)
All thermoplastics commonly used in the automotive industry for their strength, lightness and processability.
Type of plant
- Manual benchtop weldersfor prototyping or small batches.
- Automatic stations integrated into production lines.
- Customised solutions with quality control.
Technical regulations and reference standards
To ensure quality and compliance, ultrasonic welding must comply with the main industry regulations:
- ISO 9001:2015 - Quality Management Systems
- IATF 16949:2016 - Requirements for the automotive sector
- ISO 21307:2017 - Guidelines for welding of thermoplastic materials
- Machinery Directive 2006/42/EC
Sonomax provides on request the technical documentation, process traceability, CE certificates and test reports.
Sonomax Srl: tailor-made automotive solutions
Based in the province of Como, Sonomax Srl is a benchmark for the design, production and customisation of ultrasonic welders high performance. The company is distinguished by:
- In-house technical expertisemechanical and electronic engineers and software developers.
- Customised solutions based on geometries, materials and volumes.
- Test laboratory for feasibility tests and prototypes.
- Training and technical assistance for start-up and maintenance.
- Integration with automations industrial and collaborative robots.
Each machine is designed to guarantee high performance, reliability over time and ease of use.
Frequently asked questions (FAQ)
Which plastics can be welded with Sonomax machines?
Sonomax welders are compatible with polycarbonate, polyethylene, polypropylene, nylon, ABS and polystyrenethermoplastics widely used in the automotive industry.
Can ultrasonic welding be integrated into an automated line?
Yes. All Sonomax solutions can be automated and integrated with robots, PLCs, vision systems and quality control software.
What is the duration of a welding cycle?
Are the welds visible externally?
Does Sonomax offer after-sales technical support?
Yes. The company provides training, remote assistance, scheduled maintenance and spare parts support throughout the territory.
Do you have a project in the automotive sector?
Contact Us for a personal consultation or to book a free test in our technical laboratory.