Pre-tensioning tool
A pre-tensioning tool or screw pre-tensioning tool is a tool for the axial pre-tensioning of screws or threaded bolts using leverage or hydraulics .
Manual screw preload
Various manually operated hand tools can also be used as pre-tensioning tools . For example, with the help of wrenches , ratchets (or ratchets), the wheel nuts of vehicles are not only tightened to the stop, but are also tightened with an undefined preload force for a wrench or with a certain preload force or a defined torque for a torque wrench.
Hydraulic screw preload
Hydraulic screwdrivers
The hydraulic screwdriver also serves as a screw pretensioning tool with a specific, adjustable torque.
Bolt tensioner
In complex technical systems such as B. Steel bridges , wind turbines , marine applications or nuclear power plants are sometimes special, hydraulic tensioning tools (English: Bolt Tensioner) are used, with which one or more threaded bolts can be tightened and pretensioned at the same time. These hydraulic pre-tensioning tools can also be permanently installed in or on a technical system and continuously monitor and regulate the pre-tensioning force using sensors and a controller . Depending on the application, the preloading tools can be arranged, for example, in a predefined perforated ring or at certain distances along a rail . One supplier of such preloading tools is SKF, known worldwide for the sale of rolling bearings .