A diaphragm-sealed valve provided with a valve cap and a valve body, a diaphragm and a plunger assembly. The diaphragm is compressibly positioned between the valve cap and the valve body. The valve body comprises a process purging channel extending along a main recess of the valve body, under a pre-formed deformation of the diaphragm. A process purging inlet passage and a process purging outlet passage, both opening on the process purging channel, allow for a purging gas to flow in the process purging channel.