Assembly / Installation Of External Filter; Preparation Of The Excavation; Placing In The Excavation And Laying The Connections; Telescope Installation - Graf Optimax 340035 Notice D'installation Et D'entretien

5. Assembly and installation of external Filter
5.1

Preparation of the excavation

So that sufficient working room is available and the filter can be evenly embedded, the sur-
face area of the excavation should exceed the filter dimensions on all sides by approximately
50 cm. The excavation slope is according to DIN 4124. The installations excavation must be
level and smooth. The depth of the excavation must be measured so that the final installation
depth of the filter underside is a maximum 1320 mm. As an under surface for setting down, a
layer of smooth sand with a grain size of 8/16 according to DIN 4226 – 1 and a layer depth of
approximately 10 cm should be used.
Important: The setting down surface for the filter must be absolutely level to ensure an op-
tional performance.
5.2

Placing in the excavation and laying the connections

The filter is installed in the prepared excavation and is then connected to the relevant pipes
etc. Attention, it is important to note that all the pipes to be installed have a must have a gra-
dient of at least 1% in the flow direction without sagging or bending downward. To effectively
reduce the rate of flow of the incoming water, a "U" bend, similar to a siphon is installed in
the pipe before the filter. This has the effect of improving filtration and so increasing the
amount of water able to pass through the filter into the tank.
Important: It is important to follow the DIN 1986 – this requires  inlet =  outlet.
5.3

Telescope installation

5.3.1 Telescope pedestrian resistant
The telescope is pressed into the filter housing
from above. For excavation depths < 900 mm
the telescopic attachment and in some cir-
cumstances, the filter housing must be short-
ened. It is important to pay attention that the
inlet pipe is not obstructed in any way by the
telescope when installed. Before pushing in
the telescope the profiled sealing ring is
placed in the housings recess. The telescope
and the sealing ring must be thoroughly coated with the lubricating soap included in the de-
livery (use no lubrication that is mineral oil based). Attention: If the lubricating soap be-
comes dry and the telescope becomes difficult to move then there is the danger that the
sealing ring will be forced out of its recess. Before filling the sealing ring must be checked
once again that it is seated correctly in position. The telescope must be sufficiently embed-
ded and supported that no forces are transferred to the housing.
5.3.2 Telescope suitable for light traffic
The telescope is installed as in Point 5.3.1. To ensure the function in areas traversed by light
traffic, the telescope must be embedded around the collar with lean mixed concrete. The
concrete encasement must be uninterrupted, 20 cm wide and approximately 30 cm deep.
Attention: It is important to use the cast steel cover. Transport vehicle weight of heavy
goods vehicles and machinery is not permitted. The telescope must be sufficiently embedded
and supported that no forces are transferred to the housing.
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