Insertion And Filling; Laying Connections - Graf 380050 Notice D'installation Et D'entretien

5.5

Insertion and filling

The tanks should be brought into the prepared
trench with a suitable device without any jolts.
Before the surround is filled the tank is filled with
around 25 cm water, the surround (round gravel,
max. grain 8/ 16mm) is then added in layers,
max. 40 cm at a time, up to the top edge of the
tank and compressed. The individual layers must
be well compressed with a hand tamper. Be care-
ful to avoid damaging the tank when compressing
the gravel. Mechanical compression machines
must never be used. The surround must be at
least 500 mm wide.
5.6

Laying connections

Wastewater must not enter the extinguishing
water tanks.
When filling, the water between the outlet of the
filling pipe and the maximum tank water level in
accordance with DIN 1988-6 must come into
contact with the free atmosphere. An air cushion
of at least 100 mm must be observed between
the maximum water level and tank cover. If nec-
essary, the tank should be protected against
overfilling.
All inlet and overflow pipes must be laid with an
incline of at least 1 % in the direction of flow
(remember that subsequent settling may occur).
If the tank overflow is connected to a public sew-
age network, in accordance with DIN 1986, this
must be protected from backflow. All control lines
must be routed in an empty pipe, which must be
laid at an angle to the tank, as straight as possi-
ble without any sagging. Any bends needed
should be produced using a 30° adapter.
Important: The empty pipe should be connected to an opening above the max. water level.
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5. Installation
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