Manhole Covers

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 SYI Manhole Cover Series (EN 124) – Maximum load allowed for various classes

–  GROUP 1: (class A 15 minimum) Test 1.5 metric ton
Areas which can only be use by pedestrians and pedal cyclists.


–  GROUP 2: (class B 125 minimum) Test 12.5 metric ton
Footways, pedestrian areas and comparable areas, car parks or car parking decks.


–  GROUP 3: (class C 250 minimum) Test 25 metric ton
For gully tops installed in the area kerbside channels of roads which when measured from the kerb edge, extend a maximum of 0.5m into the carriageway and a maximum of 0.2m into the footway.


–  GROUP 4: (class D 400 minimum) Test 40 metric ton
Carriageway of roads (including pedestrian street), hard shoulders and parking areas, for all types of road vehicles.


–  GROUP 5: (class E 600 minimum) Test 40 metric ton
Areas imposing particularly high wheel loads, e.g. docks, aircraft pavements.


–  GROUP 6: (class F 900 minimum) Test 90 metric ton
Areas imposing particularly high wheel loads, e.g. Aircraft pavements.

The standard specifies that the designer is responsible for making the appropriate choice of class and where there is any doubt regarding the class to be used, a higher class should be selected.

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Material — Ductile iron and Grey iron:

– Microstructures of the two types: 

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– The difference between ductile iron and traditional grey iron: The addition of magnesium at the molten stage transforms the flakes of graphite which are common with the grey iron casting process and transform them into spheroidal or
nodular form. The nodular structure provides a higher tensile strength as well as a higher “strength to weight”ratio when compared with the properties inherent with grey iron manufacture.

– The benefit of ductile iron: Ductile iron high strength to weight ratio allows for the production of light weight castings that offer what can amount to a 50% weight saving over traditional grey iron.

 

Most of the standard sizes are available.
Ask SYI Sales Representatives for more details at info@syifoundry.com