Hydraulic percussion/pressing device

A hydraulic device comprising a valve housing (1) with a movable valve body (2) arranged inside the valve housing, at least a hydraulic chamber (115) provided inside said valve housing (1), and at least a control mechanism (4) for the control of said movable valve body (2), wherein the valve housing (1) comprises a plurality of combined elements (102, 103, 104), at least two of said elements (103, 104) being co-axially arranged relative to each other so that an annular space (128) is formed between said two parts;

• the valve body (2) is substantially sleeve-shaped and arranged inside said annular space (128) in the valve housing (1);
• and said valve body (2) is provided with a plurality of apertures (250, 251, 252;
• 206, 202) to make a flow of hydraulic liquid possible in the radial direction through the valve body (2), characterised in that the valve body (2) is provided inside the valve housing (1) in such a way that it is substantially balanced with reference to the hydraulic forces acting in the radial direction;
• that said valve body in the vicinity of said apertures is provided with edge portions (272A, 272B) at both the inner and outer surfaces of the valve body, which edge portions (272A, 272B) interact with edge portions (103C, 104C) and channels (160, 164) provided inside the valve housing (1), so that hydraulic liquid is allowed to flow from each one of said channels and between each of said edge portions, wherein the valve body (2) is positioned inside the valve housing (1) to allow a flow of liquid to and from said hydraulic chamber (115);
• and that said edge portions at a second position of the valve body (2) interact in a sealing manner, so that the hydraulic liquid cannot flow to or from said hydraulic chamber (115).