Abstract: A hydraulic screw tensioning device includes a tubular body, with a through opening and an annular cylinder chamber surrounding the through opening and a tubular piston movably supported in the tubular body and connectable to a screw to be tensioned. The tubular piston includes a stepped outer portion and divides the annular cylinder chamber into a first pressure chamber and a second pressure chamber. The second pressure chamber is closed by an annular end cap secured to the tubular body. The first pressure chamber is connectable to a pressure source for hydraulic fluid. The second pressure chamber is connectable to a pressure source for a compressible medium via a conduit connector mounted on the annular end cap. The conduit connector extends radially in relation to a geometric axis (A-A) of the tubular body. A damage protecting structure is provided to protect the conduit connector against accidental physical damage.

Abstract: A hydraulic screw tensioning device includes a tubular body, with a through opening and an annular cylinder chamber surrounding the through opening and a tubular piston movably supported in the tubular body and connectable to a screw to be tensioned. The tubular piston includes a stepped outer portion and divides the annular cylinder chamber into a first pressure chamber and a second pressure chamber. The second pressure chamber is closed by an annular end cap secured to the tubular body. The first pressure chamber is connectable to a pressure source for hydraulic fluid. The second pressure chamber is connectable to a pressure source for a compressible medium via a conduit connector mounted on the annular end cap. The conduit connector extends radially in relation to a geometric axis (A-A) of the tubular body. A damage protecting structure is provided to protect the conduit connector against accidental physical damage.

Abstract: A hydraulic tensioning apparatus for tensioning a threaded member (2) having a thread, comprising: a hydraulic tensioner (1), having a body (4) and a pressure space (13) for hydraulic fluid and having a thread engaging member (7) arranged to engage the thread of the threaded member (2) and to be urged away from the body (4) on introduction of hydraulic fluid into the pressure space (13) so as to tension the threaded member (2); a displacement sensor (11, 12) arranged to measure a linear displacement of the thread engaging member (7) relative to the base (4) and to provide an output indicative of the linear displacement; a rotation sensor (65, 66) arranged to determine a rotation of a nut (3) rotating on the threaded member (2) and arranged to produce output indicative of a rotation angle of the nut (3); and a control unit (80) arranged to take as inputs the outputs of the displacement sensor (11, 12) and the rotation sensor (65, 66), and to determine from the output of the displacement sensor (11, 12) a requi

Abstract: A hydraulic screw tensioning device includes a tubular body, with a through opening and an annular cylinder chamber surrounding the through opening, and a tubular piston movably supported in the tubular body and connectable to a screw to be tensioned. The tubular piston includes a stepped outer portion and divides the annular cylinder chamber into a first pressure chamber and a second pressure chamber. The second pressure chamber is closed by an annular end cap secured to the tubular body. The first pressure chamber is connectable to a pressure source for hydraulic fluid. The second pressure chamber is connectable to a pressure source for a compressible medium via a conduit connector mounted on the annular end cap. The conduit connector extends radially in relation to a geometric axis (A-A) of the tubular body. A damage protecting structure is provided to protect the conduit connector against accidental physical damage.