A cask vehicle, more specifically a cask wagon or a tank truck, for transporting a fluid or semi-fluid material, preferably in the form of slurry or the like, comprises a tank body defining a chamber for housing the material and means for conveying the material, which connect the housing chamber with the outside environment, more specifically to allow the suction of the material inside the chamber; respective valve means are provided, which are designed to open or close the passage of material between the conveying means and the material housing chamber; the valve means are of the gate-like type and comprise a respective shutter body defined by a corresponding blade or plate that is movable in a translating way in a respective transversal plane; the vehicle further comprising means for unloading the material that remains trapped in the material conveying means connecting the housing chamber with the outside environment; said means provided for unloading the material that remains trapped in the material conveying means being in the form of means for automatically actuating the unloading of the material; said means provided for unloading the material that remains trapped in the material conveying means comprising means which are designed to provide a pressure condition in the material conveying means, more specifically corresponding to the atmospheric pressure or to the pressure of the environment outside the vehicle, such as to allow or induce the unloading of the material from the conveying means; said means that are designed to provide a pressure condition in the material conveying means comprising opening means, which opening means are made in the material conveying means; capping means being provided that are designed to open and close the opening means, and more specifically the connection of the opening means with the source generating the pressure condition such as to allow or induce the unloading of the material from the conveying means and, more specifically, that are designed to open and close the communication with the outside environment; the opening means being in connection with the means that are designed to provide an unloading pressure condition of the material through corresponding duct means; more specifically the duct means have having a respective end mouth at and in communication with the opening means and a respective opposite end mouth, which opposite end mouth being designed to be put in communication with the source that provides a pressure condition in the material conveying means such as to allow or induce the unloading of the material from the conveying means; the openable and reclosable capping means being especially at, and designed to open and close, the opposite end mouth; the cask vehicle being characterised in that the respective opposite end mouth of duct means is at the valve means; in that said capping means comprising surface means for closing the connection of the opening means with the source generating the pressure condition such as to allow or induce the unloading of the material from the conveying means and, more specifically, to close the communication with the outside environment, and a respective hole to open the communication with the source generating the pressure condition such as to allow or induce the unloading of the material from the conveying means and, more specifically, to open the communication with the outside environment; and in that the respective hole is provided in the single capping body, said capping body being in the form of a plate defining the shutter body of the valve means.