Safety valve for a hydraulic system comprising oil, , said safety valve comprising: - an inlet ; - an outlet ; and - a channel ; wherein, for the safety valve , a maximum operating flow rate value Q m of the oil is predefined, and wherein the channel is suitable to guarantee an operating oil flow from the inlet to the outlet , the operating oil flow having a flow rate comprised between zero and the maximum operating flow rate value Q m ; wherein the safety valve further comprises emergency blocking means positioned along the channel ; and wherein the emergency blocking means are adapted to be actuated by an oil flow rate along the channel which exceeds the maximum operating flow rate Q m and are suitable for closing the channel ; wherein the emergency blocking means comprise a shutter adapted to move between an open position and a closed position of the channel , and a spring for which a preload value is predetermined, and wherein the preload value of the spring can be adjusted during the operating life of the safety valve ; characterized in that the channel comprises a main channel and an auxiliary channel , and in that the emergency blocking means are adapted to be actuated by an oil flow rate along the auxiliary channel . - an inlet ; - an outlet ; and - a channel ; wherein, for the safety valve , a maximum operating flow rate value Q m of the oil is predefined, and wherein the channel is suitable to guarantee an operating oil flow from the inlet to the outlet , the operating oil flow having a flow rate comprised between zero and the maximum operating flow rate value Q m ; wherein the safety valve further comprises emergency blocking means positioned along the channel ; and wherein the emergency blocking means are adapted to be actuated by an oil flow rate along the channel which exceeds the maximum operating flow rate Q m and are suitable for closing the channel ; wherein the emergency blocking means comprise a shutter adapted to move between an open position and a closed position of the channel , and a spring for which a preload value is predetermined, and wherein the preload value of the spring can be adjusted during the operating life of the safety valve ; characterized in that the channel comprises a main channel and an auxiliary channel , and in that the emergency blocking means are adapted to be actuated by an oil flow rate along the auxiliary channel . wherein, for the safety valve , a maximum operating flow rate value Q m of the oil is predefined, and wherein the channel is suitable to guarantee an operating oil flow from the inlet to the outlet , the operating oil flow having a flow rate comprised between zero and the maximum operating flow rate value Q m ; wherein the safety valve further comprises emergency blocking means positioned along the channel ; and wherein the emergency blocking means are adapted to be actuated by an oil flow rate along the channel which exceeds the maximum operating flow rate Q m and are suitable for closing the channel ; wherein the emergency blocking means comprise a shutter adapted to move between an open position and a closed position of the channel , and a spring for which a preload value is predetermined, and wherein the preload value of the spring can be adjusted during the operating life of the safety valve ; characterized in that the channel comprises a main channel and an auxiliary channel , and in that the emergency blocking means are adapted to be actuated by an oil flow rate along the auxiliary channel . <EOS>