When it comes to the production of micro-coils or electromagnetic coils, the winding process gets involved. The coil winding process involves different activities, such as wrapping, casting, glueing, and soldering. You can choose an efficient manufacturing company to get all these coil winding services. In this article, we will discuss the coil winding process and the challenges of different coil winding services. We will describe micro-coil manufacturing and what a manufacturer needs to possess to conduct an effective coil winding process.
What Is a Coil Winding Process?
The coil winding process is a method of twisting or winding very thin wires around a central core or a pin. The wires that get involved in the winding process should provide effective conductivity. Manufacturers also need to coat the wires through an isolation process before using them for the winding process. Isolating the wires is crucial to protect the wires against heat damage. There are plenty of challenges that a manufacturing company has to face during the coil winding process.
- Size constraint is one of the major challenges during the winding of micro-coils. Manufacturers overcome this challenge by selecting a very thin ultra-fine wire for the winding process. The diameter of this wire may range from 58 AWG to 61 AWG (Approximately 9 microns) and this is why the manufacturers can prepare micro-coils of 0.8 mm wide using this wire.
- Another critical challenge for the winding process is providing an effective connection between two tiny wires. Here the problem is that the tine wires can not tolerate the connecting methods of traditional heat-based soldering methods. The most used solution for this problem is Thermo-Pressure Bonding Technology.
- As the winding services prepare the foundation for the medical device designers to use micro-coils in several miniaturized applications, therefore, these services have to be very effective.
How to Manufacture the Micro-Coils?
By winding an isolated wire around a core through a specialized method, manufacturers build micro-coils. However, manufacturers can also build micro-coils of different shapes and coreless coils by using a particular-shaped core and removing the core after the coil winding process. Due to their smaller size, coreless coils have noteworthy use in vein insertion.
Sometimes, customers require higher number o windings, for example, 1000 or 2000. In this case, the coil size will also rise. To maintain the size of the coils, manufacturers minimize the diameter of the wire. Minimizing the diameter of the wire is not a simple job, because it can result in reaching the isolation breakpoint of the tiny wire. Specialized equipment and expertise are essential to conducting this process.
- The use of insulated copper wire is very common for the manufacturing of micro-coils due to the excellent conductivity of this metal. Nevertheless, several other metals are useful for various application areas.
- Bifilar coil winding process involves twisting or winding of two wire strands together. As this process involves two parallel wires, this process helps to reduce the inductance of the coil. In some medical devices where high sensitivity and outstanding fill factor are required, bifilar coils are efficient.
Manufacturing of the Different Types of Micro-coils:
The use of materials and the size of the coils can differ based on the application area.
- Even though most micro-coils consist of copper wire, manufacturers can also use several other conductive materials for the purpose of the application, such as gold, aluminium, silver, and titanium.
- The size and shape of the micro-coils can also vary depending on the space availability in the device and the required magnetic field.
Connectivity between Ultra-Fine Wires:
In medical devices where micro-coils take place, there are other components. Therefore, it is important to build the connection between micro-coils and other components of the device. As far as it is about building a connection between the components using ultra-fine wires or connecting two ultra-fine wires, laser-micro soldering processes and traditional heat-based soldering processes are ineffective. These methods can lead to heat damage, isolation damage, poor conductivity, oxidization on the joints, degraded connections, etc.
The only way to overcome this connectivity issue is the use of Thermo-Pressure Bonding Technology. Most manufacturers use this technology to connect two similar wires as well as two wires with different materials and diameters. By using this method, coil winding manufacturers can get highly reliable and strain-free connections.