Insertion And Filling; Laying Connections - Graf 380601 Notice De Montage Et D'installation

5.3

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 indi-
vidual layers must be well compressed with a hand tam-
per. Be careful to avoid damaging the tank when com-
pressing the gravel. Mechanical compression machines
must never be used. The surround must be at least
500 mm wide.
5.4

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 in-
cline 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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5. Installation
maximum
water level
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