April 2019

41 www.drivesncontrols.com April 2019 CONVEYORS AND MATERIAL HANDLING n What does the palletiser safety standard mean? I n January of this year, EN 415-4: 2017 – Safety of packagingmachines. Palletisers andDepalletisers was published and harmonised with the Machinery Directive. While EN 415-4 has always been the standard that should be followed for the safe operation of palletisers, it was originally published more than 20 years ago and was only ever harmonised to the old Machinery Directive. In 2009, the old Directive was replaced by the new Machinery Directive 2006/42/EC, which meant that EN 415-4 ceased to be a harmonised standard and that, technically, there was no longer a standard for palletisers and depalletisers. During this time, TÜV SÜD’s advice was to continue using EN 415-4 until its revision was published, as this approach indicated“best practice”, and showed due diligence on the part of the machinery owner. Defined as a C standard, EN 415-4 gives detailed safety guidelines for a particular machine or group of machines. This means that the provisions of this standard take precedence, if they are different from those that are stated in type A (basic design guidelines and terminology) or B (one safety aspect or type of safeguard, which can be used across a wide range of machinery) standards. It also now includes the extent to which hazards, hazardous situations and events are covered. For example, the 1997 version covers the process, with hazards being identified in isolation. The new version of EN 415-4 is much more detailed, describing specific types of system and indicating their corresponding requirements. Likewise, auxiliary equipment such as grippers and other machines for pallets is included for the first time, and corresponding requirements are also specified. To prevent unintended lowering of lifting systems, EN 415-4 now specifies measures for ropes or similar devices, hydraulic or pneumatic equipment. Most importantly for machinery end-users, they must understand that it is the machinery manufacturer’s responsibility to describe the safe procedures and measures. Also, to ensure machine safety and efficiency, the machinery manufacturer is now responsible for specifying in the instructions what the pallet quality requirements are. Another significant change is that EN 415-4 has introduced detail in relation to automatic guided vehicles (AGVs). This aligns the standard better with industry practices, because many more processes are now automated. These include the automated movement of pallets by AGVs, such as moving pallets to a palletiser, stretching wrapping materials, and transporting pallets within a warehouse. An informative annex (C) details the design criteria for the safety of a multi- station palletiser served by an AGV. The new standard also introduces guidance to determine the stability of stacked pallets, while Section 5 covers the requirements to prevent pallets falling. It states that where pallets are stacked automatically, the pallet magazine must be fitted with a sensor to prevent overloading. Likewise, for manual forklift stacking, the magazine must be fitted with a top bar, cover, or sensor to prevent overloading. Another informative annex (A) gives guidance on the method for assessing the stability of loads, looking at the prevention of slipping and overturn. Another new annex is D, which covers the safety aspects for an integrated palletising system, could prove invaluable to machinery end-users. It could be used as the basis for a checklist, especially where various machines, or partly-completed machines, which form part of a single integrated palletising system, are supplied by different manufacturers. In this case, the standard states that the end- user, or the integrator appointed by the end- user, is responsible for performing the specific tasks outlined in the standard. So, using this annex as a checklist could prove to be useful as part of the machine safety process. The new version of EN 415-4 has been updated to take into account a wealth of new machinery technologies, such as: the increasingly widespread use of industrial robots; the additional risks posed by palletising and depalletising systems; and additional measures to minimise risk. It also extends its scope to associated equipment. New technologies add a layer of safety compliance complexity and a Puwer assessment should be completed before any new machinery enters operation. n The EN 415-4 safety standard covering palletisers and depalletisers has been updated and harmonised with the Machinery Directive. Paul Taylor, UK head of industrial products at the product testing and certification organisation TÜV SÜD, explains the significance of this move and what it means for machinery users. Injuries caused by palletising operations can be serious, or even fatal, if the right safeguards are not in place