... control valve 2,DN: DN15-DN200 3,Materials:ceramic 4,Certificates:ISO9001 Ceramic water level control valve Standards: 1,Material: ... The parts contacting with the media are made of ceramic material, whose chemical stability and hardness (Rockwell hardness HRC90 ... resistance, corrosive resistance, ablative resistance, thermal insulation, and small thermal expansion.3, The manufacture of the ball uses ...