A gate valve for a chemical plant including a valve housing having an upper opening and an opposite lower opening; an upper sealing seat and a lower sealing seat disposed on the valve housing; a valve gate movably disposed in the valve housing, for blocking a path between the openings in a closed position and opening said path in an open position, the valve gate comprising a first plate having lower surface with a blind recess and a second plate at least partially disposed in the blind recess; wherein, in the closed position, the upper sealing seat sealingly engages the first plate, the lower sealing seat sealingly engages the second plate and the second plate is at least indirectly in contact with the first plate.