Injection of gases requiring passivation

DANGER

danger

Fluorine mixtures

Fluorine mixtures are extremely toxic and corrosive gases. Heavy reactions may occur if fluorine mixtures are applied to non-passivated surfaces or in combination with (air) humidity.

  1. If the fittings are used for gas mixtures with a fluorine content of up to 10%, the purging and passivation regulations must be strictly observed.
  2. Do not use for gas mixtures with a fluorine content > 10%.
  3. Use of gas mixtures with a fluorine content > 10% only after consultation!

DANGER

danger

Passivation

During passivation, local heating occurs as a result of the chemical reaction taking place.

  1. Before passivation, the entire gas-wetted surface must be flushed with purge gas!
  2. The temperature of the armatures must be monitored throughout the process. It may not exceed 50°C.

The passivation must be carried out in stages. In the first stage, the fluorine content may not exceed 1%. In the further stages, the concentration may be increased by a maximum of 1% in each stage. Overall, this passivation must consist of at least 3 stages.

If the entire system is filled after the first stage, the gas mixture must remain in the system at about 1 bar for at least 12 hours.

The entire system must then be purged and the next stage can be introduced.

When the concentration corresponds to the process gas and the last stage is completed, the outlet pressure can be slowly increased to the required process gas pressure.

NOTICE

notice

Passivation is also recommended for these gases, among others: HF, NF3, BF3, PF5, ClF3 as well as BCl3, HCl and Cl2.
The gas supplier must be consulted before carrying out the procedure.