5.3.4 Connection of several tanks
Two or more tanks are connected via the assembly surfaces by means of GRAF special seals and basic
pipes (to be provided at construction site).
The apertures must be drilled to the
corresponding size using only the GRAF
special crown bit. It must be ensured that
the distance between the tanks is at least
600 mm. The pipes must project at least
200 mm into the tanks.
5.4
Insertion and filling
The tanks must be inserted, impact-free,
into the prepared trench using suitable
equipment. The tank is filled with 1/3
water before filling in the tank surrounding.
Afterwards
the
surrounding (roundgrain
gravel, max. grain size 8/16) is then filled
in layers of max. 30 cm steps and is
compacted. The individual layers must be
well-compacted
(manuel
Damage to the tank must be avoided
during
compaction.
compaction machines must not be used
under
any
circumstances.
surrounding must be at least 500 mm
wide.
5.5
Routing connections
All feed and overflow pipes must be routed
with a decline of at least 1% in the direction
of flow (possible, subsequent settling must
be taken into consideration in this case). If
the tank overflow is connected to a public
sewer, this must be protected against reflux
by means of a lifting station (mixed sewer)
or
reflux
seal
(pure
according to DIN 1986.
All suction, pressure and control lines must
be routed in an empty pipe, which must be
routed as straight as possible, without
bending,
to
the
tank
Necessary bends must be formed using 30°
moulded sections.
Important:
The
empty
connected to an aperture above the max.
water level.
w w w .graf.info
5.
Installation and assembly
tamper).
Mechanical
The
rainwater
sewer)
with a decline.
pipe
must
be
Sew er
18 / 50