We have a contractor doing a field fix for one of our connections and our delegated connection designer is proposing using a KB-TZ2 Wedge Anchor installed in the face of a concrete wall. However their connection is showing connecting a threaded rod to the TZ2 using a coupling nut.
I don't know if there is enough room to keep the TZ2's nut on the wedge anchor, so I have two questions:
- Is it okay to remove the nut and washer from the Kwik bolt provided it was initially installed to the proper torque? I have seen some testing documents that state to remove the nut when testing as required, so I wonder if it would be okay to keep the nut removed after installation?
- Is it okay to use a coupling nut on the end of the Wedge anchor? I know there is the dog point at the end of the anchor bolt and am unsure if Hilti would prohibit or discourage the use of a coupling nut.
Hi Henry,
For the KB-TZ2, the nut and washer are part of the tested, qualified anchor assembly. If the fixture needs to be serviced, then the nut and washer may be removed, but the nut and washer must be retorqued to the original value when reinstalling. Leaving the nut and washer permanently off the anchor or substituting an alternative nut is not covered by Hilti’s testing or approvals.
The included nut and washer should be used to install the anchor prior to attaching the coupler. In general, Hilti expansion anchors have not been tested with couplers, and the coupler may need to be evaluated separately. If a coupler is used, care must be taken to not negatively influence the installation torque applied to the anchor. It is recommended to select an anchor length that is sufficient to achieve the required embedment depth, fixture thickness, and nut and washer height. Additional anchor length may be needed for a coupler.
Regards,
Katelyn