Application

Conveyor Platforms, Walkway and Stairs are utilised in installations where equipment is installed at high level, and maintenance access is required.  Platforms and walkways may be mounted from building columns, floor, ceiling or a combination of all three, depending upon the requirements of the customer and the design of the building.

Steelwork is configured to suit the system requirements and is designed in accordance with BS 5395, BS5950 and/or the legislation of the country in which the Baggage Handling System is installed.

Platforms and Walkways

When there are a concentration of conveyors or handling devices at high level, these will often be mounted on a platform structure, rather than using a matrix of walkways for access.

All platforms and walkways should have handrails around all open sides. Toe plates shall be provided around all open sides of the platform and walkways and beneath the first step of any open riser stair.

The clear width to the side of the conveyor should be a minimum of 750mm.

Typical walkway arrangements:

Typical platform arrangement:

Stairs

Stair access will generally be used where operator access is required, and ladders normally for occasional maintenance activities. Clear width should be minimum 750mm. The maximum pitch shall be 30o for straight stairs in general use and 42° for occasional access.

Landing design will follow the recommendations for platforms and walkways.  The length of the landing should be not less than the clear width of the stair or 850mm, whichever is the greater.

Straight stairs and landings shall have continuous handrails on both sides as shown below.  Helical and spiral stairs shall have handrails on the outside.

Ships Ladders

Where ladders are used for access, preference is given to ship’s ladders if space permits, otherwise normal fixed ladders are used.

For a ship’s ladder, the width between stringers shall be in the range of 450-550mm, with the slope in the range of 65-75°. 

All rises shall be uniform and in the range 225 - 255mm.

 A single handrail shall always be provided on both sides of a ship’s ladder. 

Fixed Ladders

Where fixed vertical ladders are used, the width between strings shall be in the range of 380 - 450mm.
A rise in a flight must be uniform and the top surface of the rung level with the platform or landing.  All rises shall be uniform and in the range 225 - 255mm

A safety cage shall be fitted whenever a user can fall 2 metres or more.

 

Conveyor Cross-Over

In some cases a conveyor cross-over may be required to pass from one side of a conveyor to the other. Depending upon spatial constraints and regularity of access, this cross-over may be made up of a pair of stairs, ship’s ladders or fixed ladder with a landing over the conveyor. In these instances the design guidelines used will be similar to that described above.

 

 

Design Loads

The design loadings will be determined to suit the specific project requirements, but typically the following guidelines can be considered:

Mezzanines and Platforms – Typically 200 to 300kg per square metre is used dependant on concentration and type of conveyors and miscellaneous devices. This value would account for the weight of the conveyor, bags and operators.  Where X-rays and Vertical Diverters are sited loading may be increased to take account of the additional load of each particular machine.

Walkways – Typically 150kg per square metre to account for operators or maintenance personnel.

Vertical deflection of beams due to imposed load: 1 in 360 of span of the beam
Vertical deflection of beams due to total load: 1 in 250 of span of the beam

Vertical deflection of floor decking to total load: 1 in 200 of span of the floor decking.

Horizontal deflections of column or hanger: 1 in 300 of the height of column or the length of hanger.