Ambika manufactures and supplies products of highest quality in adherence with the BS, ES, ISO 9000 series of quality systems. The production facilities is constantly upgraded. Our physical, chemical and sand testing laboratory are most up to date and we keep record of all the testing as per ISO 9000 requirements. We have in- house pattern making and light machinery arrangements for faster services to our customers. We are also in process of obtaining ISO 9001 certification.

EXTRACTS FROM EN 124 : 1994

The appropriate class of manhole top or gully to to be used depends upon the place of installation. The various places of installation have been divided into groups numbered 1 to 6, as listed below.

The figure shows the location of some of these groups in a highway environment. A guide as to which class of manhole top or gully should be used is shown in parentheses for each group. The selection of the appropriate class is the responsibility of the designer. Where there is any doubt, the stronger class should be selected.

Group 1 (min. Class A 15)
Areas which can only be used by pedestrians and pedal cyclists.

Group 2 (min. Class B 125)
Footways, pedestrian areas and comparable areas, car parks or car parking decks.

Group 3 (min. Class C 250)
For gully tops installed in the area of kerbside channels of roads (as per figure) which when measured from the kerb edge. extend a maximum of 0.5 m into the carriageway and a maximum of 0.2 m into the footway.

Group 4 (min. Class D 400)
Carriageway of roads (including pedestrian streets), hard shoulders and parking areas, for all types of road vehicles.

Group 5 (min. Class E 600)
Areas imposing high wheel loads e.g. docks, aircraft pavements.

Group 6 (min. Class E 900)
Areas imposing particulars high wheel loads, e.g. Aircraft pavement.



Materials
6.1 General
6.1.1  Manhole tops and gully tops
Manhole tops and gully tops with the exception of grantings of granting shall be made from either:
                        a) flake graphite cast iron.
                        b) spheroidal graphite cast iron.

6.2 Production, quality and testing
The production, quality and testing of the materials designated below shall comply with the following ISO standard or Euronorms:

Flake graphite cast iron
              ISO      185      1988 
Spheroidal graphite cast iron
              ISO      1083    1987


Design Requirement
7.1 General
Gully tops and manhole tops shall be free of defects which might impair their fitness for use.
Where there is no detailed specification shown in this standard for any particular requirement, the manufacturer shall state such specification in his documentation.

7.3 clear opening of manhole tops for man entry
The opening of manhole tops designed for man entry shall comply with the safety requirements in force at the place of installation. Generally this is considered to be at least 600 mm diameter.

7.4 Depth for insertion
Gully tops and manhole tops of classes D 400, E 600 and F 900 shall have a depth of insertion A (see Clause 3, No. 12) of at least 50 mm.

This requirement does not apply if the cover or grantings are made secure in their position against displacement by traffic by a locking device but such devices are not included in this standard.

7.6 Seatings
The manufacture of gully tops and manholes tops shall be such as to ensure the compatibility of their seatings. For classes D 400 to F 900 these sitting shall be manufactured in such a way as to ensure stability and quietness in use. This may be achieved by machining of the contact surfaces, use of cushioning inserts, threepoint suspension design or any other appropriate method.

7.9 Slots dimensions
The dimensions of slots in granting shall be selected having regard to the hydraulic capacity and the slots shall be evenly distributed over the clear area. The water way area shall not be less than 30% of the clear area and shall be given in the manufacturer's catalogue.

7.16 Frame depth
The depth of the complete frame of manhole or gully tops of class D 400, E 600 and F 900 shall be at least 100 mm.



Testing
Gully tops and manhole tops shall be tested as complete units in their condition of service.
Compliance with the loading requirements for the appropriate class be determined by the loading test.

8.1 Test Loads
For Gully tops and manhole tops with a clear opening equal to or greater than 250 mm, the test load is shown in the table 6 for each class. where the clear opening is less than 250 mm, the test load shall be that shown in tables 6, multiplied by CO/250.