The danger points on sheet-fed folding machines must be guarded. The two main types of machine, buckle and combination, give rise to similar risks. Noise can be a particular problem and will need to be addressed by, for example, the provision of suitable noise hoods for the buckle plates.
On new machines noise reduction measures should have been provided as part of the machine’s standard specification.
The main in-feed rollers should be provided with fixed guards with a narrow slot for sheet entry. Access to the folding rollers should be prevented by a combination of guards, the machine’s frame and the buckle plates.
In-running nips associated with drive tapes should be guarded. This can be achieved by designing the transport/feed tables to ‘fit’ the pulleys, i.e. – reach to a point within 4mm of the in-running belt/pulley nip or the provision of nip bars. Particular attention should be given to the nip points associated with tensioning pulleys. Therefore, fixed guard should be installed.
The dangerous intakes associated with folding knives should be guarded. On modern machines this may be in conjunction with the delivery area of the buckle folding unit, i.e. – an all-enclosing interlocked guard. On older machines a more localised fixed or interlocked guard should be provided.
Perforators, creasing units and slitters are often fitted to this type of machine. The intakes associated with these devices should be guarded, as should any in-running nip created between them and fixed parts of the folding machine. This second identified nip often occurs at the delivery area of the buckle folding unit. Precautions also need to be taken to prevent access to the periphery of running slitters and perforators.