O Ring mounting for an ultra-high vacuum application . Pressure distribution within the cross-section of the O Ring. The red lines are hard surfaces, which apply high pressure. The fluid in the seams has lower pressure. The soft O Ring bridges the pressure over the seams. Orings are one of the most common yet important elements of machine design. They are available in various metric and standard sizes. The UK standards sizes are known as BS Sizes and typically range from BS001 to BS932. The most common standard sizes in the US are controlled by SAE AS568. In general orings are specified by the inside diameter and the cross section diameter (thickness). The O Ring is one of the simplest, yet most engineered, precise, and useful seal designs ever developed.
The typical working temperature range is -50°C to +100°C.