I was wondering if there are any tips or advice for securing a Viton gasket on a CF flange. One of our flanges would be opened frequently to access our samples but in trying to close it, so we cant ...
Hot zones are the hearth of every vacuum furnace. When purchasing a new furnace, you might face with the Hamletic doubt about hot zones: graphite-based or all-metal design hot zone? That’s the question! The graphite wafer is an excellent material. It allows operation at very high temperatures (up toRead more
Hot zones are the hearth of every vacuum furnace. When purchasing a new furnace, you might face with the Hamletic doubt about hot zones: graphite-based or all-metal design hot zone? That’s the question!
The graphite wafer is an excellent material. It allows operation at very high temperatures (up to 3000°C based on the vacuum level), has low density, reduced weight and modest thermal capacity. It creates the ideal black body conditions (emissivity about 1) inside the heating chamber for obtaining high uniformity.
All-metal hot zones are used in high demand industries where sensitive materials are processed, such as aerospace, electronics and medical. There are heat treatments that require a particularly clean environment or extreme vacuum levels. There may be different reasons: in some cases the chamber’s graphite could interfere with the process, resulting in unwanted carburation of the pieces treated. In other cases, the load could be particularly sensitive to the presence of residues in the oxygen or hydrogen atmosphere (which could lead to embrittlement of the pieces), and so graphite wafer degassing during the cycle could be damaging. In these circumstances, the user should opt for all-metal heating chambers (shields and resistor).
If you want more information on this topic and a detailed analysis of the differences, take a look at the following 2 articles:
Vacuum furnace hot zone: graphite vs all-metal design [1/2]
Vacuum furnace hot zone: graphite vs all-metal design [2/2]
Securing a Viton gasket on a ConFlat (CF) flange can be challenging because Viton gaskets aren't specifically designed for the knife-edge seal of CF flanges, which are typically used with annealed copper gaskets that form a metal-to-metal seal. However, since you're looking for a reusable solution fRead more
Securing a Viton gasket on a ConFlat (CF) flange can be challenging because Viton gaskets aren’t specifically designed for the knife-edge seal of CF flanges, which are typically used with annealed copper gaskets that form a metal-to-metal seal. However, since you’re looking for a reusable solution for frequent access, there are a few tips and alternative approaches you could try.
Summary of Options:
- Use vacuum-compatible grease to hold the Viton gasket in place.
- Consider magnetic or temporary adhesive solutions.
- Machine an O-ring groove into the CF flange if permanent modifications are acceptable.
- Explore elastomeric seal adapters or switch to flanges with O-ring grooves.
- Ensure careful alignment during closure to avoid shifting the gasket.
- Check for proper alignment.
- Consider spring-loaded Viton seals.
- Consider CF-Compatible O-Ring Seals.
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