Ultra-pure, non-reactive, elevated-temperature seal assembly
US5971402A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Oct 31, 1997 |
| Grant date | Oct 26, 1999 |
| Priority date | — |
| Expiry date | Oct 31, 2017 |
Classification
- Technology area (CPC F)Mechanical Engineering; Lighting; Heating
- CPC primaryF16J15/106
- WIPO fieldMechanical elements
- WIPO sectorMechanical engineering
Abstract
Sealing assemblies are illustrated for heaters, pumps, conduits, and the like for handling process fluids used in the semiconductor-processing industry. Clean, particle-free, nonreactive, non-trapping, ultra-pure, thermally tolerant, sealed systems are required to maintain process fluids with contaminant levels below parts per billion, or even trillion. A lip seal connects a tube, having a lip at each end, to a face of a creeping material. A creeping fluorocarbon sealing material may form the interface for reducing stress concentrations on the tube, and for providing a consistent reliable seal between the lip and the creeping face. A face seal between creeping faces may be effected by a creeping sealant there between. The faces may be loaded entirely by their own creeping structural materials. No flanges are required. In certain embodiments, retaining rings may be provided for preventing unrestrained creep of sealing assemblies. Heat soaking may accelerate primary creep and expanded fluorocarbon materials may provide creeping sealants having inherent dimensional stability in at least one dimension without relying on fillers or fibers of other materials.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.