Vacuum unit is an equipment to purge gases from the die before molten metal is charged into the cavity. It consists of vacuum exhaust valve for blocking the molten metal, vacuum pump, vacuum tank, control panel, trap, etc. Product quality depends on the vacuum rate in the cavity.
The effectiveness of this technology to improve quality has been proven by wide range of researches, and it is adopted by many diecasters who produce complicated high quality products. By sucking and discharging gases generated during injection process, injection in the cavity is stabilized, and various troubles resulted from back pressure caused by negative pressure can be diminished. Furthermore, it improves the production efficiency, and enabales after-treatments e.g. surface treatment like plating, heat treatment and welding that were not possible in the past.