It is a filtration device for preventing foreign matter from entering, which is installed in the lower part of the piping of the foam chamber fire extinguishing system. Foreign substances such as sand, rust and metal impurities are filtered by
the built-in metal screen and accumulated at the bottom of the outer part of the screen. And foreign substances generated by corrosion inside the pipe connected to the foam chamber are accumulated at the bottom of the inner part of the screen, thereby preventing degradation due to foreign substances when discharging foam. Re-assembling is also easy after
removing foreign materials by detaching the lower cover flange.