When cryogenic and vacuum seals start to degrade over time, whether due to heat, thermal cycling, or constant pressure, they may need replacement to maintain functionality. If the device is still usable, the indium seal can often be renewed by following these steps:
- Disassemble the indium sealing, ensuring to carefully remove any remnants of the previous gasket material on the flanges or mating surfaces.
- Use a razor blade, scraper, or putty knife to remove as much of the old indium gasket material as possible. For highly sensitive seals, a soft cloth can be used instead of mechanical means. In some cases, gently warming the area can help soften the indium gaskets material for easier removal.
- For seals using indium as the gasket material, if any traces remain on the flanges after scraping or wiping, a 10% solution of HCl can be applied to eliminate them. Ensure to rinse thoroughly with deionized (DI) water, followed by acetone, and allow to air dry or use nitrogen for blow drying.
- Once the preparation is complete and the surfaces are clean, the new indium gasket material can be installed.