Applications of the Diamond-Edge Gaskets Sealing for the Ultrahigh Vacuum Systems

Gao-Yu Hsiung^1*

¹Instrumentation Development Department, National Synchrotron Radiation Research Center, Hsinchu, Taiwan

* Presenter:Gao-Yu Hsiung, email:hsiung@nsrrc.org.tw

Various types of the metallic (Aluminum) Diamond-Edge (DE-) gaskets for the Flat (DEF-) flanges and the applications for the ultrahigh vacuum (UHV) systems are introduced. All the vacuum chamber built with flanges and the gaskets are made of aluminum alloys and produced by the oil-free Ethanol-CNC-machining process. The cross section of the DE-gaskets fit the DEF-flanges not only for the circular profile but also the non-circular profiles, e.g. race-track, rectangular, key-hole, et al. All the chambers with gaskets after ethanol-machining can be assembled without any chemical cleaning. The standard circular DE-gaskets was designed to suit the CF-flanges of the commercial UHV products that can be directly mounted to the DEF-flanges. Several applicable vacuum systems, e.g. for the outgassing rate measurement, were produced and tested. The quality of the UHV at pressure < 20 nPa after vacuum baking has been approved. The non-circular aluminum DE-gasket sealing can be applied for the high radiation reactors, accelerators, wave guides, aluminum ultrahigh vacuum systems, and aluminum chambers for industrial products. The DEF-flanges can be directly machined on the vacuum chambers that won’t take any risk of damage on the sealing surfaces. It results in the consequent advantages of flexible design, higher systematic reliability and lower manufacturing cost.

Keywords: aluminum chamber, ultrahigh vacuum, metallic gasket, sealing, non-circular flange