5.3
Joining multiple vessels
The coupling of two or more tanks is achieved by means of assembly areas moulded into the bases of the
tanks using special plastic weld connections and canalisation pipes. It is important to note that the
distance between the tanks is minimum 1000 mm or 1300 mm if the tanks are to be installed side by side.
5.4
Placing and filling
The tanks are guided and placed into the
excavation using suitable equipment and
without any knocks. (see also point 4 –
Transport and storage)
To avoid deformation of the tank during the
embedding/back fill process, it is important to
first fill the tank to 1/3 with water and then to
begin back filling and embedding/compacting
in even layers of no more than 300 mm until
the 1/3 level. Following this the tank must be
filled to 2/3 with water and the process of
filling in layers of 300 mm repeated until the
2/3 level is reached, each layer must be well
compacted with a hand tamper. Repeat the
process
until
the
embedded. Care must be taken during the
embedding to ensure the tank is not
damaged. Under no circumstances should
powered compacting machines be used. The
surrounding back fill must be at least 500 mm.
When installing the tanks in an area to be traversed by light traffic (passenger cars) there must be a
final bearing layer of coarse gravel approximately 200 mm to 300 mm deep. The area of the bearing
layer of coarse gravel must be equivalent to the base of the excavation.
Backfill material:
The filling materials must be ideal for compacting, permeable, shear resistant, remain frost free
and contain no sharp objects.
These qualities are accomplished with smooth sand and not exceeding the grain size 8/16
according to DIN 4226-1.
Excavated earth or "fill sand" are in most cases unsuitable.
Earth, clay and other impermeable soils are not suitable for back filling/embedding.
5.
Installation and assembly
tank
is
completely
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