Low Pressure Injection Molding

Mar 30, 2023 Cable Overmolding

Low pressure injection overmolding (LPIO) is a process used to encapsulate and protect electronic components, such as cable assemblies, from environmental factors like moisture, dust, and vibration. This process involves injecting a liquid thermoset material into a mold cavity and curing it to create a solid, durable, and waterproof coating around the assembly.

Cable assemblies are used in various industries, including aerospace, automotive, and medical, to connect different components and transfer data or power. These assemblies can be exposed to harsh environments, including extreme temperatures, chemicals, and physical stress, which can damage or compromise their performance. Overmolding cable assemblies with a protective material enhances their durability and longevity, ensuring reliable and consistent performance.

LPIO has several advantages over other encapsulation methods, such as potting and manual encapsulation. It is a cost-effective and efficient process that reduces labor costs, material waste, and cycle time. The low pressure used in LPIO also eliminates the risk of damaging delicate electronic components during encapsulation, ensuring a high-quality finished product.

To begin the LPIO process, a mold is designed and manufactured to match the shape and size of the cable assembly. The mold is then mounted onto the injection molding machine, and the cable assembly is positioned inside the mold cavity. A liquid thermoset material, typically a two-part epoxy or polyurethane, is then injected into the mold cavity under low pressure, filling the voids around the cable assembly and creating a solid, watertight seal.

The curing process takes place in the mold, and the time and temperature required depend on the specific material used. Once cured, the mold is opened, and the finished overmolded cable assembly is removed. The excess material is trimmed off, and any necessary secondary operations, such as connector assembly, are performed.

LPIO can be used to overmold various types of cable assemblies, including single wires, bundles, and connectors. The finished product is lightweight, flexible, and can withstand harsh environments, making it ideal for applications such as sensors, control systems, and power distribution.

Overall, LPIO is a reliable and efficient encapsulation process that offers several benefits for cable assemblies. It enhances their durability and longevity, reduces the risk of damage, and improves overall performance. As technology advances and the demand for smaller, more complex electronic components increases, LPIO will continue to play an essential role in ensuring their protection and reliability.