Xylem FLYGT Compit 901 Series, Installation, Operation And Maintenance Manual

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1
0.7 m
1 m
0.3 m
5
WS011558C
5
4
6 7 8
2
3
Dimensions in the figure must be regarded as minimum dimensions.
1. Geotextile
2. Backfill
3. Remaining fill
4. Ground insula-
tion
5. Unit insulation
6. Plastic access
cover
7. Concrete ac-
cess cover
8. Paving, as-
phalt, concrete
1. Check that the following requirements are fulfilled:
– The unit must be level after backfilling.
– Backfilling must be correctly made around inlet pipes, outlet pipes, and the unit bottom.
– The pipe work and the electrical connections must be protected and supported during backfilling so that
no load is applied to them by the compaction operation.
– The backfill must not contain any contamination, such as snow or ice of significant importance.
– Backfilling is done with crushed material, grain size 2–36 mm (0.08–1.42 in).
– The remaining fill must not contain stones larger than 50 mm (1.97 in).
2. Execute filling and compaction layer by layer around the unit, up the unit wall and up the pit wall.
Minimum thickness of backfill around the unit 0.7 m (2.3 ft)
Layer thickness 0.15 m (6 in)
a) Start the compaction on the first layer by driving a light, vibrating machine around the unit.
Cover the whole surface.
b) When the first pass is completed, then start the second pass.
c) When all the passes for a layer are completed, then fill the next layer.
d) Repeat the compaction procedure until all layers have been compacted.
3. Do the remaining fill before the groundwater surface is allowed to rise above the crushed material.
4.2.14 Installing the access cover
Install a plastic access cover
en - Original instructions
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