00 0290 395 0 - RHB C 490-C 370 - 03/09
15
1 Introduction
General repair instructions
44966
Pre-assembly
– Cut off the tube at right angles.
Do not use a pipe cutter! This will slant the tube
wall, causing heavy inside and outside burrs.
– Slightly deburr the inside and outside tube ends.
Do not chamfer!
– Clean the tube end.
In case of tube bends, the straight tube end up to
where the bending radius starts must be at least twice
the height of the union nut.
– Push the union nut and the profiled ring on
the tube.
– Push the tube against the stop in the union and
tighten the union nut until the profiled ring catches
the tube.
The tube must not rotate.
This point can be felt because increased power is
needed from here.
– Tighten the union nut half a turn beyond the point
where resistance is felt.
– Check the cut produced by the cutting edge:
A visible collar must fill up the space ahead of the
profiled ring face. The profiled ring may rotate, but
axial displacement must not be possible.
Final assembly
– Insert the pre-assembled tube into the well-oiled
screw fitting.
– Tighten the union nut until considerably more
force is needed and then add another half a turn.
Important:
Back up the threaded joint with
a spanner!
Repeated assembly
– Every time the profiled ring fitting has been loos-
ened, retighten the union nut until resistance is
felt and then continue for half a turn beyond that
point.
Important:
Back up the threaded joint with
a spanner!
Profiled ring fitting leaks
If a fitting leaks, first loosen the union nut until some oil
escapes and then tighten it as specified.
Any deviating tightening torques reduce the rated
pressure resistance and the service life of the screw
fitting. This results in leaks and the tube slipping out.
