Spin Welding Process, Material Considerations

Section 7 - Optimizing Performance

Spin Welding Process

The formal definition of spin welding is “An assembly process in which thermoplastic parts with rotationally– symmetric mating surfaces are joined together under pressure using unidirectional circular motion. The heat generated during the rotational contact melts the plastic in the heat–affected zone forming a weld upon cooling.” Note that the parts themselves can be any shape, only the mating surfaces to be welded need to be circular.

The spin welding process is divided into five distinct phases. In Phase I, the rotational friction generates heat. Frictional heating is intensified with both axial (press vertical) and joint surface velocities. In Phase II, the friction results in abrasive forces which strip off surface roughness, generating wear particles causing the surfaces of the polymer to begin to melt. As the polymer reaches its crystalline melting point or glass transition temperature, it enters Phase III, where heat starts to be generated by internal friction within the molten region. This continues in Phase IV, where the temperature of the molten layer remains relatively constant. Because plastics are poor conductors of heat, the surface heat is transferred slowly to the interior and much of it remains localized. At this point, the rotation is stopped and we enter Phase V where the molten material

.is allowed to cool under pressure for a short period called the Hold Time.

Material Considerations

Materials that can be friction (i.e. vibration) welded can also be joined with by spin welding. The semicrystalline thermoplastics are more readily joined using spin welding than ultrasonics. Using compatible polymers, spin welding is capable of making reliable hermetic seals. Far–field welding is easier with spin welding than with ultrasonic welding. Additional parts can be entrapped between the upper and lower pieces during spin welding.

Joining of dissimilar polymers is possible using the spin weld process although it generally produces lower strength weld joints. By designing the weld joint with an undercut, the polymer with the lower melting temperature will flow into the undercut, creating a mechanical union.

Dukane Manual Part No. 403-570-01

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403570-01 specifications

The Dukane 403570-01 is a sophisticated ultrasonic welding machine renowned for its versatility and efficiency in various industrial applications. Designed with advanced technology, this model is favored in sectors such as automotive, medical, textiles, and consumer goods for its ability to provide consistent and reliable weld results.

One of the main features of the Dukane 403570-01 is its state-of-the-art ultrasonic transducer, which converts electrical energy into mechanical vibrations. This high-frequency sound wave technology allows for the joining of materials without the need for additional adhesives or fasteners, making it an environmentally friendly and cost-effective solution for manufacturers. The transducer operates at a frequency of 20 kHz, optimal for producing strong and durable welds.

In addition to its transducer, the 403570-01 is equipped with an advanced generator that provides precise control over the welding process. This generator adjusts the energy output based on the materials being welded and the specific application, ensuring optimal settings for each job. The machine also features a user-friendly control panel that allows operators to easily program and monitor welding parameters such as time, power, and pressure.

The 403570-01 is designed for ease of use and maintenance. Its modular design simplifies servicing and allows for quick replacement of components, ensuring minimum downtime. Additionally, the machine’s lightweight construction enhances portability, making it suitable for both dedicated production lines and on-the-spot repairs.

Another significant characteristic of the Dukane 403570-01 is its versatility in handling various materials, including plastics, metals, and composites. This flexibility opens up a wide array of welding applications, from assembling intricate medical devices to automotive components. Furthermore, it features integrated safety measures that protect both the operator and the machine, reducing the risk of accidents during operation.

In summary, the Dukane 403570-01 stands out due to its advanced ultrasonic technology, user-friendly controls, and versatility in handling various materials. With its robust design and efficient welding capabilities, it is an invaluable asset for manufacturers looking to enhance their production processes and maintain high-quality standards.