Health and Safety
Executive / Commission
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Woodworking Sheet No 20
Cross-cutting veneer guillotine
This Information Sheet is one of a series prepared by HSE's Woodworking National Interest Group in agreement with the Woodworking Machinery Suppliers Association. The guidance is confined to manually loaded machines of all sizes.
The main source of danger with these machines is through contact with the knife either during a cutting operation or whilst blade changing. Injuries have also been caused by the clamping mechanism and through contact with transmission machinery.
Safeguarding the sides and rear
Access to the knife and clamp at the sides and rear of the machine should be prevented, either by fixed or by interlocked guards. Any openings in the guards should conform to Appendix A of see Code of practice for safety of machinery1. Where scrap is removed from the rear of the machine, the back guard should be designed to accommodate this, for example by the use of a simple rake, the fitting of an inclined chute or the use of an interlocked guard or off-cut bin.
Where access to the blade and clamp is prevented by an interlocked guard or off-cut bin, then a single control system interlock with the knife and clamp drive is sufficient (see Code of practice for safety of machinery1 Section 9.3.7). On microprocessor controlled machines interlocking should not be through the programmable electronic system. The interlocking system should be such that when the guard is opened, or the off-cut bin is removed, movement of the blade and clamp is stopped or reversed before the operator can reach them, and no further movement of the clamp or blade is possible until the guard is closed.
Where the opening at the front of the machine is restricted to comply with the safety distances given in Appendix A of see Code of practice for safety of machinery1, a fixed guard may be used. In most cases however, either an interlocked hinged front guard or a photoelectric safety system is used, in conjunction with a two hand control device.
Where an interlocked guard is used, any openings in the guard should be restricted to comply with the safety distances given in Appendix A of see Code of practice for safety of machinery1. Dual channel control system interlocking using two position switches with positive and negative opening operations (one per channel) which are cross monitored should be used (see Code of practice for safety of machinery1 Section 9.3.5). The guarding system should be arranged so that if the guard is opened, movement of the blade and clamp is stopped or reversed before the operator can reach them, and no further movement of the blade or clamp is possible until the guard is closed.
Any photoelectric trip device used for safeguarding the front of the machine should be designed in accordance with Specification for electrosensitive safety systems to machinery2 Parts 1 and 2, and installed in accordance with the guidance given for a category 1 machine in Application of photoelectric safety systems to machinery3. Interruption of the photoelectric curtain during a dangerous part of the cutting cycle should cause the knife and clamp to stop or begin to retract before the operator can reach them. It must not be possible for the knife and clamp to be set in motion again until the safety system has been restored to its fully guarded condition. Full compatibility between the guillotine control system and the safety system is essential.
On machines fitted with interlocked guards or photoelectric safety devices, it should only be possible to start a cut by operating a two hand control. Two hand electrical controls should comply with Electrical equipment at industrial machines Part 14. In particular:
Dangerous movement of the blade should only be possible with the blade and clamps in the fully guarded condition. If a blade changing key is used, then this should not interfere with the operation of the two hand control device.
Regular maintenance and inspection of guards and safety devices is essential in order to ensure safe operation. Guillotines should be maintained and inspected in accordance with the supplier/manufacturer's instructions and written records of any maintenance and inspection should be kept.
Photoelectric safeguarding methods do not provide a physical barrier between the operator and clamp and knife. The effectiveness of the safeguard therefore depends not only on the reliability of the photoelectric safety system, but also on the ability of the clutch and brake or the hydraulic control valves to respond reliably to the control signal. For this reason, a stringent safety inspection routine is necessary, including tests carried out at the beginning of each shift and after knife changing. Details of these tests will be found in the manufacturers handbook and a written record of tests and their results should be kept on or near the machine on an operator's test record sheet.
Additional advice and information can be obtained from local offices of the Health and Safety Executive. The address and telephone number of local offices can be found in the telephone directory under Health and Safety Executive.
Further copies of this Information Sheet may be obtained from the Woodworking National Interest Group, Health and Safety Executive, 14 Cardiff Road, Luton, LU1 1PP. Telephone (0582) 34121.
This publication may be freely reproduced, except for advertising, endorsement or sale purposes. The information it contains is current at 6/92. Please acknowledge the source as HSE.
Printed and published by HSE NIS/08/20 C150 6/92