Content

1. Composition of Leeds Line?
2. Product classification and functions of Leeds line?
3. Different Leeds lines are applied separately?
4. Conclusion

1. The role and composition of the Leeds Line 

Leeds wire is composed of multiple single stranded insulated wires and is widely used in applications that require good flexibility and high-frequency performance.
High frequency Leeds wire is made up of multiple insulated single wires twisted together, usually used for operating frequencies at 10 kHz Up to 5 MHz The application between them. In the application of magnetic energy storage coils, high frequencies will generate eddy current losses. Eddy current losses increase with the increase of current frequency. The root cause of these losses is the skin effect and proximity effect, which can be reduced by using high-frequency Leeds lines. These losses caused by magnetic fields can be overcome through the twisted structure of Leeds wires.

The basic unit of composition for the Leeds line is a single stranded enameled wire. To meet different application requirements, various optimized combinations of conductor materials and insulation paints can be extracted.





All single stranded enameled wires are produced on specially designed painting machines, and painting is a continuous process mainly composed of annealing, insulation paint coating, curing, lubricant coating, tension control, and wire arrangement.




1) Annealing
During the drawing process, the grain structure of the bare wire has changed after cold deformation. Annealing process can cause copper material to undergo recrystallization and become softer again. In order to avoid surface oxidation of the wire, this high-temperature stress relief process is carried out in an environment with protective gas. If the wire oxidizes, it will affect the adhesion between the copper wire and the insulation coating during the subsequent painting process. The flexibility of the wire is very important for good winding characteristics, especially for significantly reducing the number of wire breaks.
2) Painting process
There are two main coating methods for wires: felt coating and mold coating. Felt coating is mainly used for the production of fine wires, while mold coating is mainly used for the production of coarse wires. The coating of insulating paint should always use as many layers as possible, avoiding the use of thin and thick coatings, in order to achieve better mechanical and electrical properties.
3) Curing Oven
The solvent contained in liquid insulation paint will evaporate in a high-temperature curing furnace, and then undergo catalytic combustion in an energy-saving and environmentally friendly manner. The temperature control during the curing process is very important. If the temperature is too low, excessive solvents will remain in the insulation paint coating, resulting in poor adhesion and reduced mechanical and electrical properties. If the temperature is too high, the paint layer will become hard and brittle, causing the insulation layer to crack under mechanical stress.
4) lubricant
The surface of the enameled wire needs to be precisely coated with a specified amount of lubricant. Lubrication of enameled wire is crucial for obtaining stable winding characteristics and ensuring zero defects under high-speed winding conditions.
5) Outer diameter control
Continuously monitor the final outer diameter of all wires using laser technology.
6) Tension Control
Continuous and stable tension control is necessary during the painting production process to ensure that the wire arrangement on the spool is uniform and consistent. By effective tension control, it is possible to avoid resistance changes in the wire due to stretching, and also ensure that the spool has good unwinding performance when used at the customer's location.
7) Flat Cable
The spacing between wires and the speed of the spool are production process variables that require close control. This results in consistent and excellent electrical winding performance, while minimizing other issues such as wire jamming and tangled wires as much as possible. The parameters of the wire laying process, such as wire spacing and spool speed, are closely controlled. Therefore, it enables the wire to have stable and good wire release performance, and minimizes the occurrence of problems such as wire clamping and tangled wires.
8) Monitor
The operator can obtain all important parameters during the painting process from the camera.
According to the number of single strand lines, Leeds line requires one or more production steps. Therefore, there are many choices for overall design. A limited number of single stranded wires are directly twisted, and each single strand is freely arranged. The single stranded wire may be in any position on the cross-section of the Leeds line. Leeds wire/harness structure:

2. What are the product categories and functions of the Leeds line?

According to the different requirements of various product application scenarios, there are multiple types of Leeds lines.
2.1 Ordinary Leeds wire: Leeds wire produced from enameled wire is suitable for applications related to high frequency or heating.
1) Advantages for high-frequency applications: reduced high-frequency losses, cost-effective design, structure that matches impedance or frequency, and the ability to use stress relief to increase tensile strength while maintaining flexibility at high conductor cross-sectional areas.
2) The advantages for heating applications include high resistance precision production, wide application range (drying, heating, preheating), a variety of conductor materials with high mechanical properties to choose from, and high heat stability.
2.2 Film wrapped Leeds wire: mainly suitable for applications that require high breakdown voltage. Thin film wrapping can improve the ability of Leeds wire to withstand bending and mechanical stress. The use of heat sealed or self-adhesive film materials for self mucosal wrapping can prevent the detachment of the film during or after the production process, thereby ensuring compliance with the specified creepage distance.
2.3 Extruded Leeds wire: Adding an extruded layer to high-frequency Leeds wire can improve flexibility, mechanical strength, chemical resistance, and breakdown voltage. Compared with ordinary structures, the bending life of extruded Leeds wire is significantly improved.
2.4 Shaped Leeds Line: Shaped (mechanically formed) Leeds Line adopts a rectangular or square cross-section with a very high filling factor, which can fully utilize the winding space. Compared to conventional circular cross-sectional structures, the filling coefficient of the fixed Leeds line can be increased by up to 20%.



2.5 Silk wrapped Leeds thread: High frequency Leeds thread wrapped with natural silk, polyester silk or nylon silk can increase mechanical properties and achieve excellent dimensional stability. Extra protection against mechanical stress, high flexibility, and no need for splicing.
2.6 Stress relief Leeds wire: The typical application of this product is not winding coils, but as a cable. The tensile strength and bending life have significantly increased, improving the protective ability of ultrafine Leeds wire against mechanical stress.
2.7 Membrane wrapped high-frequency Leeds wire: commonly used in transformer designs that require simplified winding processes and reduced size, weight, and materials
2.8 Smart Twisted Wire: This self-adhesive Leeds wire has excellent bonding strength, good flexibility, fast weldability, and excellent hot air self-adhesive properties. The hot air self-adhesive process is more environmentally friendly than solvent self-adhesive, and also supports high-speed winding and process automation.

3. Different Leeds lines are applied separately

1) Ordinary Leeds wire: usually used in high-frequency transformers, choke coils, switching power supplies, hearing aids, sensors, ballasts, heating resistance wires, motors and other products.
2) Ordinary Leeds wire: usually used in high-frequency transformers, choke coils, switching power supplies, hearing aids, sensors, ballasts, heating resistance wires, motors and other products.
3) Extruded Leeds wire: commonly used in heating resistance wires, hearing aids, and other products.
4) Fixed Leeds line: usually used in wireless charging, induction cookers, high-frequency transformers, electric motors and other products.
5) Silk wrapped Leeds wire: usually used in high-frequency inverters, converters, induction chargers and other products.
6) Stress relief Leeds line: commonly used in products such as the automotive industry, industrial electronics, medical applications, and smart textiles.
7) EFOLIT ® Membrane wrapped high-frequency Leeds wire: usually used in EV （ Electric vehicles) OBC （ Car charger) DC/DC Converter, wireless charging, charging station SMPS （ Switching power supply, high-frequency transformer, high-frequency sensor, high-frequency choke coil and other products.
8) Smart twisted wire: usually used in wireless charging transmitting coils, wireless charging receiving coils, wireless coils for various applications, and other products.



4. Conclusion

GOTREND is a green enterprise committed to global sustainable development. In our company philosophy, it is stated that, GOTREND The vision of the enterprise group is to establish a dream enterprise that strives for sustainable growth, learning, creation, profitability, and happiness for every employee, partner, customer, and investor, and helps bring about a better world of life. We respect healthy and sustainable lifestyles (LOHAS), support actions to better protect the environment, and are committed to designing, manufacturing, and producing energy-efficient and environmentally friendly products. If you have any questions or would like to further understand the relevant information, please feel free to contact us service@gotrend.com.tw