Hydraulic flange bracing  

The tensioning of flange connections using a hydraulic power pack is a tried and tested method that is preferably used for tensioning bolts in the M20 to M48 range. 

With the correct approaches for friction coefficients and a specified sequence of bolts to be tightened in several steps, the tolerance of force application is approx. +/- 3% of the calculated installation bolt force.

Alternatively, or as a supplement, electric screwdrivers can now also be used to screw in the M20 to M30 range within the same tolerance range.

  Bolt stretching process  

The stud tensioning method is the most precise tensioning method for flange connections because it works without friction. Hydraulic cylinders are used to tension the bolts with their calculated force, then the nut is screwed onto the flange by hand and the bolts are untensioned again. The "pulled" force is retained. This method is particularly suitable for thread sizes M52 to M110 / UN1" to UN4", in high-pressure applications or for tensioning RTJ flange connections.

  Flange service  

For us, flange service means

• Tightening of flange connections of all types as a service, including, if necessary, determination of the tightening torques (pre-testable by notified bodies) and preparation of the assembly documentation.                                                                                                
• Provision of a supervisor for the assembly of sensitive flange connections - independent of material delivery by our company
• Follow-up inspection of flange connections in compliance with EN1591-4 and our works standards 357 and 362

In all these cases, we guarantee the full functionality of the flange connection for all inspected components and all supervised work processes.