Pivoting valve to regulate the flow of a fluid comprising: - a body (2a, 2b) that includes; - an inlet hole and an outlet hole for the fluid flow path, - a shutter element of the fluid flow path mounted pivotable on a rotating shaft of the valve body (2a, 2b) to be able to rotate from an open position to a closed position of the fluid flow path, - a tubular element to channel the flow of fluid inside the body (2a,2b) of the valve, the tubular element being located between the inlet hole and the outlet hole, and mounted linearly, so that it can be moved from the outlet hole to the inlet hole when the shutter element is in the open position, - means to actuate the displacement of the tubular element inside the body, (2a, 2b), said means comprising a mechanism (10, 11) provided with a first actuating element capable of being actuated from the outside of that body (2a, 2b), including that mechanism (10, 11) transmission means (11a, 11b) for transmitting the movement of that first actuating element to the tubular element that is housed inside the body (2a, 2b), characterised in that said first actuating element is rotary and said transmission means (11a, 11b) include a gear associated to said first actuating element and to a rack joined to the tubular element, said tubular element being susceptible of being displaced when said gear is actuated, wherein the rack is arranged in a groove of guide provided in a surface of the tubular element. - a body (2a, 2b) that includes; - an inlet hole and an outlet hole for the fluid flow path, - a shutter element of the fluid flow path mounted pivotable on a rotating shaft of the valve body (2a, 2b) to be able to rotate from an open position to a closed position of the fluid flow path, - a tubular element to channel the flow of fluid inside the body (2a,2b) of the valve, the tubular element being located between the inlet hole and the outlet hole, and mounted linearly, so that it can be moved from the outlet hole to the inlet hole when the shutter element is in the open position, - means to actuate the displacement of the tubular element inside the body, (2a, 2b), said means comprising a mechanism (10, 11) provided with a first actuating element capable of being actuated from the outside of that body (2a, 2b), including that mechanism (10, 11) transmission means (11a, 11b) for transmitting the movement of that first actuating element to the tubular element that is housed inside the body (2a, 2b), characterised in that said first actuating element is rotary and said transmission means (11a, 11b) include a gear associated to said first actuating element and to a rack joined to the tubular element, said tubular element being susceptible of being displaced when said gear is actuated, - an inlet hole and an outlet hole for the fluid flow path, - a shutter element of the fluid flow path mounted pivotable on a rotating shaft of the valve body (2a, 2b) to be able to rotate from an open position to a closed position of the fluid flow path, - a tubular element to channel the flow of fluid inside the body (2a,2b) of the valve, the tubular element being located between the inlet hole and the outlet hole, and mounted linearly, so that it can be moved from the outlet hole to the inlet hole when the shutter element is in the open position, - means to actuate the displacement of the tubular element inside the body, (2a, 2b), said means comprising a mechanism (10, 11) provided with a first actuating element capable of being actuated from the outside of that body (2a, 2b), including that mechanism (10, 11) transmission means (11a, 11b) for transmitting the movement of that first actuating element to the tubular element that is housed inside the body (2a, 2b), characterised in that said first actuating element is rotary and said transmission means (11a, 11b) include a gear associated to said first actuating element and to a rack joined to the tubular element, said tubular element being susceptible of being displaced when said gear is actuated,