De-tensioning procedure 100% bolt to tensioner ratio configuration

See also Tensioning Preparation for the safety instructions.

  1. Fit the Tensioners to the bolts and connect the link hoses. See also Tensioner System Configuration for configuration guide and see Tensioner Installation for an installation guide.

  2. Before commencing pressurization, back off all of the thread inserts by 5mm (0.2”). Ensure there is still enough thread engagement between the thread inserts and the bolt thread protrusions.

  3. For pump operation refer to the supplied pump instruction document. Operate the pump unit and pressurise the system to 1000psi (70 bar) and check that the pressure is holding steady. If the pressure drops investigate the problem looking for leaks.

  4. Once the pressure is holding steady, continue to slowly increase the pressure, continually monitor a single joint nut (tensioner end) for rotation. Use a tommy bar inserted into the nut socket. Once the break loose pressure (BLP) is found, stop the pump to hold the pressure and make a note of the pressure. Once the pressure is holding steady, continue to slowly increase the pressure, continually monitor a single joint nut (tensioner end) for rotation. Use a tommy bar inserted into the nut socket. Once the break loose pressure (BLP) is found, stop the pump to hold the pressure and make a note of the pressure.

    Break Loose Pressure (BLP) is the pressure at which the user can rotate one of the joint nuts (tensioner end) by hand.

  5. Make sure the pressure is holding steady and using a tommy bar inserted in the nut socket, back off every joint nut (tensioner end) by 3mm (1/8”). Do not back off the nut to a greater value than the distance that you backed off the thread insert in step 2.

    If the nuts are difficult to rotate at this break loose pressure, slightly increase the pressure until the nuts become loose. Never exceed the maximum working pressure of the tensioner. Make sure that the bolt material and joint material can withstand the load you are applying.

  6. Slowly release the pressure to zero.

  7. Using a tommy bar, tighten down the thread inserts to fully close the pistons. Repeat until all of the pistons are fully closed.

  8. Disconnect all hoses and remove all tensioners from the joint.

  9. The de-tensioning procedure is complete.