An automatic ring valve 10 comprising a valve seat 12 provided with a plurality of gas flow passages 14 arranged according to at least one annular row, at least a shutter 18 comprising at least one ring-shaped portion for selectively closing and opening the gas flow passages 14, wherein said ring-shaped portion of the shutter 18 comprises a fiber-reinforced matrix 40, at least one contrasting member for contrasting an opening movement of ring-shaped portion of the shutter 18, wherein said ring-shaped portion of the shutter 18 comprises a structural core 18A made by said fiber-reinforced matrix 40, and wherein at least a portion of said structural core 18A is covered by at least one primary layer 18B, designed to improve fracture and/or impact and/or wear resistance of said ring-shaped portion.