The direct sewage electric ball valve can be used as a pipe connector in water supply and drainage, water supply and other pipeline systems under the conditions that the material selection of the direct sewage electric ball valve needs to meet. The material selection of electric ball valve for direct sewage supply shall meet the following conditions: 1. The body and gland of electric ball valve for direct sewage supply shall be of integral casting structure, cast with resin sand, and made of nodular cast iron GGG50, which meets the requirements of DIN1693, with strength greater than 500MPa and elongation greater than 10.
It is higher than QT400-10 and has high strength and corrosion resistance. When bearing the maximum pressure difference of the pipeline, the stress shall not exceed 1/5 of the tensile strength of the material. 2. All valve seals are made of NBR, and the valve raw materials are from Bayer, Germany. All sanitary, mechanical, physical and corrosion resistance indicators meet the requirements of German DVGW, so as to ensure that the service life of the valve gate is 35 years under normal conditions. The valve has excellent wear resistance, resilience, cavitation resistance, aging resistance and acid and alkaline resistance.
3. The limit valve pipe of electric ball valve for direct sewage supply is Q235-A.
4. Fasteners shall be Q235-A with galvanized surface.