Challenge Europe’s business policy has always been to provide the fullest of support to their customers in all aspects of fastener supply. This has often involved anticipating changing demand patterns during those periods of industrial upheaval, especially now seen in the medical device industries.
During difficult times both suppliers and customers will usually look to reduce stock holding, whereas we at Challenge will increase stocks. We recognise that in the ‘little and often’ scenario created by recessions, pandemics and the like, customers need an instantaneous response to their needs. Our ability to meet difficult demand situations spills over into being able to provide and support Kanban, VMI and other supply to line systems which can be infinitely adapted to suit individual customer needs.
The Challenge service does not stop at supplying goods, but includes a total partnership support package as illustrated below.
In recent years, the complex nature of fasteners has tending to be overlooked or misunderstood. Due to the wide range of specifications it often proves difficult for design and production engineers to decide upon the most suitable fastener for specific applications.
Whilst International Standards will provide comprehensive information on things like fastener diameters, lengths, materials etc., we should not assume that the entire range listed in a particular Standard will be available from stock as standard product range – so even “standard” fasteners may require specialist sourcing and supply arrangements.
Reference to these international standards will provide detailed specifications for thread tolerances and other information on the geometry of fastener threads, while considerations of other configuration requirements, such as the specific drive type required, can be integrated in the final design. Similarly, for material selection, including steel; stainless steel – Austenitic, Ferritic or Martensitic; plus, brass, bronze, aluminium, copper and plastics of many sorts.
The increased use of CAD systems can be seen as a solution but often compound the problem of selection since they can correctly identify dimensional requirements but not necessarily the appropriate material or tensile strength.
Associated with this is the problem that ultimately one can never know completely how a fastener will function in-situ until you try it. Which is why accelerated aging trials and extended excess load tests are frequently performed to ascertain a realistic safety margin. Guidelines from hard-won experience can normally be accessed, but sometimes an unusual situation needs to be evaluated or perhaps a replacement of the exact same type is simply not available and a suitable replacement is required. It is easy and tempting to over-specify, but Challenge Europe can help.
This generally occurs in applications where there are issues of weight and space but where cost is secondary because of the safety critical nature of the situation. However, sometimes, given a minimum lifetime expectancy, there can be a tendency to “play it safe” and add a safety margin on top of a safety margin, leading to gross over-specification, e.g. going up one or two sizes with consequent weight and space implications, or maybe calling for an exotic and expensive alloy where a lower-cost high-grade treated steel would be more appropriate. Over-specifying one fastener may not be a problem but over-specifying thousands can make a big difference overall.
Again, with the help of the Challenge Europe partnership support package, assistance can be provided in not only the choice of suitable specifications but also those specifications most readily available and hence most economic in use. Samples can be made available for testing and proving purposes as an additional aid to correct selection.
Typically, this covers stainless steel machine screws, self-tapping/thread-forming screws and steel chipboard screws. Of increasing popularity are self-drilling types such as SPAX – which have a special thread form to cut into timber without a pilot hole – and HECOFIX screws, also with a range of specialised threads, both especially designed for professional users.
In some cases, it is not always possible to avoid the use of a customized fastener and Challenge Europe are also able to advise and support such requirements. For maximum benefit consultation at the concept/design stage is recommended where proper advice can cover screw type, hole sizes, clearances, torque settings etc. For example, we find that people often use self-tappers in plastic without realising that there are specialist designed-for-plastic screws – and only find out later that ordinary self-tappers can bind in the hole where they snap off or split the component.
Challenge (Europe) Ltd
Tel: 01234 346242
Email: sales@challenge-europe.co.uk
