The valve cartridge comprises an insert with a sleeve (25) for a valve piston (27), and a ring (26) between the sleeve and the valve cover (13). Either the sleeve or the ring has a discontinuity area (56) in the surface (45) towards the other part. This area forms an open connection between inside and outside of the sleeve. The discontinuity is formed by a recess, or a groove in the end face of the sleeve. A radial seal (33) is located between sleeve and ring.
