Seals for Helium Leak Tests
Helium is a commonly used leak test gas because its small, lightweight molecules can easily detect the tiniest leaks. In addition, helium is inert and more environmentally friendly than some alternatives, making it much safer to use. Helium, however, is highly permeable to most traditional seal materials, such as thermoplastics and rubbers, when exposed over short periods. An excellent candidate to consider in designing your leak test is thermoset polyurethanes. This unique material provides the physical properties necessary to create reliable and repeatable seals for helium leak tests.
Advantages of Polyurethanes for Helium Leak Tests
1. Thermoset polyurethanes are formed through the chemical reaction between a polyol and diisocyanate. Due to their versatile cross-linked chemical structure, thermoset polyurethanes can display a much higher density than their counterparts. As a result, this makes thermoset polyurethanes not permeable to helium and a dependable solution for helium leak test seals.
2. Unlike most thermoplastics and rubbers, thermoset polyurethanes can be customized to meet exact geometry and performance requirements. For example, thermoset polyurethanes can be chemically engineered into a solid or foam and display varying levels of superior physical properties such as compression set, hardness, and tensile strength, to name a few. For this reason, thermoset polyurethanes enable product engineers to design seals that fit perfectly within their testing environment.
Helium leak testing is a highly efficient form of leak detection that can provide dependable results when employed with the appropriate material. Because of this, helium leak testing is commonly used in applications such as medical devices, packaging, and military & defense, which are typically required to meet stringent requirements. Employing the appropriate seal material in your helium leak test design can considerably reduce false test results and improve reliability for extended periods. Thermoset polyurethanes enable product engineers and OEMs the ability to maintain product quality and avoid downtime or additional costs that may be associated with troubleshooting false results.
If you find thermoset polyurethanes are a key requirement for your helium leak test, this can easily be customized by your thermoset polyurethane manufacturer. For material assistance, complete our design tool here, or click the button below to start your custom polyurethane seal today.