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Modular aluminium profile systems are often used for machine guarding, though care has to be taken to ensure that aluminium is, for the particular application, more functional or cost-effective than fabricated steel or modular steel perimeter guards.
Aesthetics is often used as an argument in favour of aluminium guarding, especially if aluminium extrusions have already been used for the machine frame, conveyors or other components on the machine. In addition, the clean appearance of anodised aluminium is often preferred to painted or powder-coated steel. After a few months of use, when a machine has received a few minor knocks, these also tend to be less noticeable on aluminium than on painted steel. Aside from the aesthetics, if machine builders do not have in-house painting facilities and therefore have to sub-contract any finishing, aluminium, once again, offers an advantage.
Corrosive environments can pose problems for steel guards. Although painting or powder coating should, in theory, provide protection, it only requires small imperfections in the finish or subsequent damage to enable rust to get a hold. In extreme circumstances stainless steel may be required, but anodised aluminium is suitable for use in most corrosive environments, provided care is taken in specifying adequately protected fasteners and accessories.
Some machines, such as canning lines, tend to have the guarding built on-site around the finished machinery. In this case, aluminium's versatility means that complete guards can be readily made-to-fit on site (rather than made-to-drawing), or partially-finished guards can be delivered to site for completion using a kit of aluminium profiles and fasteners - and a simple set of tools.
Modular aluminium systems are also easier to adapt and modify, thereby saving time and labour costs. So, for example, if a machine is likely to evolve after the guards have been installed, or if it is known that upgrades, modifications or repairs are likely in the future, aluminium is usually preferred over steel. Cutting, drilling and attaching threaded fasteners to aluminium profiles is also cleaner than welding, and in some situations (such as on-site modifications) welding may be difficult or prohibited.
In some cases there may be a weight limit for the machine or the guarding - especially if the guards are regularly or even infrequently opened or removed, perhaps for loading/unloading parts or for maintenance. The lower density of aluminium can be a distinct advantage over steel here - and some manufacturers of aluminium profiles offer ranges of lightweight profiles with adequate stiffness, specifically for applications where weight is an issue.
If cost is the major consideration, there are circumstances where aluminium is almost certain to prove the best option. These include projects where modifications will definitely be required either before commissioning of the machine or at a later date, and projects where the guarding is complex and labour-intensive - perhaps involving sliding or lifting guards. In complex designs, the time saved by using aluminium profiles and accessories is likely to more than offset any additional materials costs.
Aluminium is also likely to be cheaper if there is a need to achieve exact fits, minimal gaps or near-perfect seals, as these would be difficult to achieve with steel unless expensive jigs are used.
While there is always a desire to minimise costs, occasionally costs have to be compromised in order to meet a deadline (or if a customer is prepared to pay more for a machine if the lead time can be reduced). Aluminium profiles can be used to good effect to save time, especially if steel frames would have to be sent to a sub-contractor for finishing. Furthermore, bolting together aluminium profiles is relatively unskilled compared with welding, so it is easy to find additional labour with adequate skills if aluminium guards need to be assembled quickly.
Procter Machine Guarding is the UK's leading supplier of bespoke and modular machinery guarding. While the company has built its reputation upon the supply of steel guarding, it recognises that there is strong demand for aluminium guarding. Procter has therefore teamed up with specialist suppliers to provide guarding constructed from their ranges of aluminium profiles and accessories. Guards can be supplied complete to customers' drawings, or Procter can undertake to design and install the guards, making use of its extensive knowledge of machinery safety standards to ensure that all legal requirements are met. This service is available for both perimeter guarding and guarding for smaller machines - such as automated assembly cells.
By sub-contracting the guarding to Procter Machine Guarding, customers benefit from faster delivery, reduced cost, and Procter's experience - which results in a better overall design. If required, the guards can be equipped with safety switches ready to be wired into the machine's safety-related control system.
To discuss any requirements for aluminium machine guards, please email
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or telephone 02920 855758.
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