Bubble-free encapsulation and casting of components in epoxy resin
Potting compounds such as epoxy resin play an important role in the electrical and electronics industries, where they serve the protection of sensitive components from moisture, dust and damage. Epoxy resin consists of two material components – the resin and a hardener with filler. When epoxy resin is being processed, the two components are filled into separate containers of a 2K metering system, metered and mixed according to a precisely set ratio. Potting resins often require processing in higher temperatures to reduce their viscosity and flow easier. Potting systems accommodate this requirement with heated storage tanks, hoses and pumps, among other things.
Often, the terms “potting”, “casting” and “encapsulation” are used interchangeably. This is simply because the process can be carried out in various ways. While the most common method involves potting a component in a case, which then becomes part of the finished unit, in the casting method, the case is removed once the compound has hardened, to produce more of a moulded unit. Lastly, components like printed circuit boards, require only a thin layer of protective film. Encapsulation or “dip coating” is a process where such components are dipped in a bath of low viscosity resin and taken out again. No matter the method, the prime purpose is always to protect against external influences and ensure the stability of the component.
As with any process, correct potting depends on getting a number of factors right. For example, the resin must have the right temperature to be of the viscosity needed for the specific application. Most importantly however, the formation of air bubbles in the potted material and in the cavities around the component must be avoided at all costs. This can be achieved with the correct configuration of the metering system.
Meter Mix® metering and mixing systems provide everything that is required for successful potting of electrical and electronic components. They are specifically designed to process low to high viscosity potting materials such as epoxies, polyurethanes or silicones in a consistent and bubble-free way. Our high quality standards are based on 30 years’ worth of experience in the engineering of metering systems for potting applications.