Brazing of automotive heat exchangers. If flux is used to clean the surfaces, this acidic material evaporates and enters the vacuum system. These vapors can attack the oil in oil-sealed pumps and can cause pump corrosion.
RUTA pump system with DRYVAC, VARODRY or LEYVAC dry-compressing screw pumps.
For this application, the use of dry-compressing screw pumps is the best choice as screw pumps can easily handle the flux outgassing of the furnace. The flux remains in the vapour phase and does exit the pump without condensing or causing corrosion.
The system operator does not have to respect shorter maintenance intervals, the usual annual oil change of a dry-compressing screw pump is sufficient.