A high pressure valve includes a body on which is fixed an electromagnet, the shell of which has a radial discal part provided with a central hole connecting an internal opposite surface to an external surface. The body is provided with a cylindrical external centring surface and with a radial support surface. The shell is arranged on the body around the centring surface, the external discal surface being in surface contact against the support surface of the body. The coil of the electromagnet is arranged in the tubular space between the body and the shell itself closed by a closure ring. The liquid-tightness between the body and the shell is ensured by a gasket compressed by a wedging washer against the centring surface and against the internal discal surface. The shell is then immobilized on the body by the wedging washer.