Bolt tensioner is a special tool for tightening or dismantling bolts using hydraulic principle.
By stretching the bolt, it is elongated within the elastic deformation zone and the bolt diameter is slightly deformed so that the nut can be easily loosened or tightened. In addition, it can be used as a device for applying axial force to hydraulic interference connections for top pressure installation.
The operating principle of the bolt tensioner is based on the tensile strength, yield coefficient and elongation of the material. When working, the power source (such as hydraulic pump) output of high-pressure oil through the high-pressure hose delivery to the tensioner’s piston cylinder, under the pressure of the piston in the piston cylinder piston upward, driven by the stretching nut upward movement. The stretching nut is threaded with the working bolt, thus elongating the working bolt, so that the bolt elongation reaches the required amount of deformation (deformation control in the elastic deformation range). Then pre-tensioning or dismantling is carried out, and finally the working bolt is returned to its original shape by means of hydraulic or mechanical return to its original position to complete the operation.
