<p>Membrane valve comprises a stationary plate (20) detachedly positioned in a valve housing (1) and formed as a radial tangent guide in its operating position. Preferred Features: A shaft seal (25) facing an adjusting drive (15) is fixed using the stationary plate and/or its holding parts. An additional holder (26) is arranged between the upper front side of the stationary plate and the shaft seal. The stationary seal and/or the additional holder are detachedly held by locking screw (28).</p>
