When you first hear the words “impregnation methods,” you might instantly think of in-vitro or in-utero fertilization. However, in the world of electronics, impregnation methods have nothing to do with bringing new life into our world.
The mass production of electronic parts, especially motors, rotors, stators, and apparatuses that require wire coiled components typically undergo a process of impregnation. This process generally involves immersing the component into an insulating liquid that hardens after it is filled.
Impregnation is a critical process that primarily serves as a method of protection for the coiled wire. Not only does this assist with protection against wire movement and mechanical damage, but it also prevents the entrance of moisture and foreign matter as well as strengthening the insulating material.
Impregnation methods all differ depending on the nature of the components needing this protective coating. Here, we’ll explore this process in detail.
Why Impregnation Matters
If you remember the days when everyone used a direct ethernet connection, you’ll probably also remember that when these wires became too hot, tangled, or dusty, your connection often slowed or was interrupted.
The same is true with many wires and their function. Basically, all wires need insulation and protection from the elements.
Uninsulated coiled wires have the tendency to attract dust, moisture, and foreign debris. If the integrity of the coil is compromised, this could result in overheating or deterioration over time. As most rotors and stators need to be relied upon to perform a specific function, the efficiency and strength of the components are only enhanced through the impregnation process.
Impregnation increases the dielectric strength of the coil’s insulation, and works to help along the coil’s heat dissipation process. All in all, impregnation protects from corrosion and internal deterioration, as well as with extreme heat which can ultimately cause a motor or stator to seize up during operation.
Types of Impregnation Methods
Depending on the nature of the components being impregnated, several different methods can be used. This largely depends on the size and shape of the component, and its primary functionality. The following details several different impregnation techniques used for different components:
The trickling method sounds just like how it works. The insulating resin is “trickled” at a steady stream resulting in uninterrupted filling without any dripping or cleaning of the components after the process is finished.
Trickling is also often referred to as “gelling” because a solid gel is produced when the component is placed in an oven after trickling to solidify the curing process.
Some of the benefits of the trickling method are as follows:
- Maximum Filling
- Minimized Handling Process
- Highest Quality
- No Rework Needed
In addition to trickling, several other methods may be utilized depending on the components.
Typically used for both stators and rotors, roll dipping requires only partially dipping the parts into the resin. The components are then rotated or “rolled” until the desired depth has been reached
In the roll dipping process, the components are usually mounted on a specialized gripping apparatus. These gripping arms continuously rotate the component around its center axis.
After the process is complete, the component is removed from the resin bath to drip.
Hot Dipping and Vertical Dipping
Though roll dipping and trickling are often the preferred methods used due to their higher efficiency, hot dipping and vertical dipping are also viable impregnation processes that can be utilized depending on the nature and design of the component.
Hot dipping involves preheating the components in order to handle thicker impregnation resin. This typically allows for a higher degree of penetration.
Vertical dipping, like hot dipping, involves the preheating of the component then a full submersion into the resin bath. The vertical dipping process, however, also involves draining the component at a specific angle then repeats the process until the entire component has been fully impregnated.
Your impregnation process will largely depend on the size and shape of your components. Awkwardly shaped rotors or stators, and depending on the depth of the central axis, are the conditions that you should consider prior to choosing an impregnation method.