Insertion And Filling; Laying Connections - Graf 381131 Anleitung

4.3

Insertion and filling

The tanks should be brought into the prepared trench with a suitable device without any jolts.
To avoid distortion, before the surround is filled the tank should be filled 1/3 full with water. The surround
(round gravel, max. grain 8/16 acc. to DIN 4226-1) is then added in layers of max. 30 cm up to 1/3 of the
tank and compressed. You should then fill the tank until it is 2/3 full and fill the trench with layers of max. 30
cm until it is 2/3 full, etc. The individual layers must be well compressed with a hand tamper. Be careful to
avoid damaging the tank when compressing the gravel. Mechanical compression machines must never be
used. The surround must be at least 50 cm wide. Filling with round gravel must be undertaken quickly
and completed in one day. Otherwise filling water may cause excess loads in the event of heavy rain.
4.4

Laying connections

All connections should be fitted to the flat surfaces
below the tank dome to ensure that the maximum
water level in the tank is below the tank/tank dome
connection.
The required holes can be produced with a circular
cutter or hole saw. When doing this, please note
that the maximum hole size is DN 110 (bottom of
end face) or 160 DN (top of end face and at tank
dome).
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). All
intake, pressure and control lines must be routed in
an empty pipe, which must be laid at an angle to
the tank, as straight as possible without any sagging. Any bends that are needed should be produced
using 30° adapters.
Important: The empty pipe must be connected to an opening above the max. water level.
Please note: In order to fit the connections, please always use materials which are suitable for drinking
water (PE screw connections, special seals, connection pipes and connection fittings).
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4. Installation and assembly
maximum water
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