vonRoll hydro CLASSIC Montageanleitung Seite 21

Fitting nuts with pre-determined
breaking point
1. The brass nuts with pre­determined breaking point may only be
tightened with 60 Nm at the most.
2. The nuts must be tightened only with a suitable torque wrench.
Otherwise, this could lead to the nut being tightened too firmly,
which would lead to early breakage of the nut.
3. The screw and the nut must not cant, this could possibly lead to
early shearing of the nut's thread.
If the top part of the fire­hydrant is removed during maintenance, it is
recommended that new nuts with pre-determined breaking point
be used. In this way a pre­determined breaking point can be guaran­
teed.
Fire­Hydrant CLASSIC with loose flange :
Before tightening the nuts with pre­determined breaking point, the
hydrant can be positioned stepless on 360°.
Correct tightening of nuts:
1. Fit all screws and tighten up manually
2. Cautiously tighten nuts across from each
other with reduced force (35 – 40 Nm)
3. Finally, tighten the nuts across from each
other with a maximum torque of 60 Nm