Industrial doors have come a long way since the days of manual handling of slow-moving, biparting shutter doors, and even when powered vertically, opening shutter doors was painfully slow. Since then, legislation, working environment and highly temperature-sensitive production processes demand a great deal more from doors, especially in demanding applications like cold stores.
As a result, door manufacturers have devised many improvements to make them more productive by way of more automated control methods and quicker, easier repairs, like crash-out facilities. But all these welcome improvements come with a higher cost so it is important to try to gauge a return on investment (ROI) and get a handle on their reliability.
First step usually involves selecting the door supplier that meets your criteria of the right price, performance specifics, reliability issues and quality of after-sales service. On the subject of after sales service reliability it would be preferable to enquire about site visits to a supplier’s clients, and stick with members of ALEM. On the price issue it is sensible to ensure one is comparing like with like when comparing quotes because door performance rates are highly variable, as are maintenance-free claims. Beware also of cheap doors because apart from reliability issues they may also pose a delay in spares deliveries.
Once a particular door type has been chosen how important is opening and closing speeds and is security an important issue? This will depend on the door user’s production environment, the nature of the goods being produced and stored, and sometimes the flexibility of the door supplier. At the Grob-Werke factory in Mildenheim, for example, who produce complex machine tools, its Efaflex highspeed doors must remain sealed and stable, even if there are large differences in air pressure because otherwise draughts could occur. Such is the nature of Grob- Werke’s production in highly insulated rooms that if its measurement instruments cool down even a little, it could take days to recalibrate them – a very costly issue for both Grob-Werke and its clients. This highlights the importance of very high door speed movements to ensure almost constant temperatures, and at 4 mt/sec the Efaflex vertical doors far exceed the typical maximum of 2.5 mt/sec offered by competitors.
A good door supplier will also be highly flexible, bending over backwards to meet a client’s specific needs. Will, for example, your supplier develop a special control system because of secrecy issues, as was the case at Audi’s Motor Sport Centre. Its door supplier provided programmed doors to stay open for the shortest possible time and were fitted with special controls so that no-one could gain unauthorised access. Doors and curtains do not have to be visible in the ordinary sense, as in the case of air curtains, which should be considered in combination with a security door, where the traffic movement is so high that the door should be kept permanently open during working hours. They offer lower energy costs (up to 30%) and safety advantages which eliminate any risk from forklifts hitting fast roller and spiral doors.