New torque suppressor cures problems of metal face seal fittings

he metal face seal fitting is the standard reusable coupler for fluid systems in semiconductor manufacturing facilities. Historically, this fitting has connected lines and components carrying semiconductor gases and liquids throughout the fab and within process equipment. Elaborate and costly strategies have been used to hide fundamental flaws of this fitting: bolting down components, clamps to prevent tube rotation, devices to lock the male and female nut together to prevent loosening, and gas manifolds with additional right angle bends to isolate sections from rotation. Even with all these precautions, technicians inevitably introduce torque in the lines, damage the toroid on each make up, generate particles, and are limited to a 1/8th-turn-past-fingertight installation regimen. This study identifies the standard metal face seal fitting as a source of particles in the range of 0.1 to 1.0 microns. Standard fittings are also prone to anomalous loosening and leakage. The OmniSafe fitting, described here, prevents these possibly catastrophic failures. How face seal fittings work