Written by Mark Jennings, Engineering Director at Dawson Shanahan
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Engineering businesses grow by employing the latest technologies to strengthen and boost the efficiency of the manufacturing process. Sustainability, which was once considered as an unwanted pressure on business, is now helping to reduce production costs and improve returns on investments by reducing waste and increasing productivity. In some cases, technologies that reduce waste also bring the welcome by-product of improved product quality.
One particularly good example of how improved manufacturing techniques and environmental sustainability has dovetailed is in the technology of cold forming – the extrusion of a part from a blank. Cold forming is a fast, economical way to produce robust, complex components in a wide range of materials. This process is capable of delivering precision engineered parts with up to 80 percent less scrap than machine processes, which, given the current economic climate, is a statistic that ought to attract the attention of any component manufacturer.
Coupled with these reduced costs, cold forming actually offers an opportunity for manufacturers across industry to take advantage of enhanced component quality.
Cold forming makes for superior quality products by plasticising metals along their grain boundaries, rather than cutting across, thus producing parts with extremely low levels of stress deformation and high levels of mechanical integrity, resulting in far greater performance and reliability. Furthermore, cold forming offers outstanding levels of definition, even on parts with complex contours. Typically, dimensional tolerances can be to within plus or minus two microns, with the added benefit of extremely fine surface finishes, which in many cases, require no further machining or polishing.
Additionally, parts undergo work hardening during the cold forming process, improving their machinability and durability still further. Work hardening dislocates the structure of the metal in a way that prevents further dislocations, resulting in a stronger component.
While the technique has long been used with other advanced engineering metals such as copper, aluminium and brass, the inherent strength of stainless steel has been something of a stumbling block for the cold forming process. For engineers today, there is now an alternative to more conventional processes using a safe cold forming technique developed by Dawson Shanahan.
This latest innovative development now means that stainless steel, as well as other exotic metals such as titanium, can be cold formed using a specialised metallic lubrication and extrusion coating avoiding the need for hazardous chemical solutions. This unique shell eliminates the problem of galling, to prevent damage being caused to the components and tooling, which often presents itself in the form of scores or surface imperfections, thus maintaining consistent quality in finished parts.
The advantages of this new process will be of particular benefit to those areas of industry requiring robust, ultra-high precision parts, such as industrial engines where the parts are used to boost overall reliability, while cutting CO2 and particulate emissions. Cold forming also delivers significant ecological benefits compared to processes such as hot forging, where the high level of heat, and thus energy, required comes at a price to the environment. Consequently, cold forming can contribute to a lower carbon footprint, as well as enhancing productivity and business performance.
Another way in which engineering manufacturers can introduce sustainability and environmentally-friendly enhancements to their production processes to deliver the responsible products that customers want and need is by reducing the use of harmful components in the process.
Dawson Shanahan recently decided to adopt an in depth review of cleaning solvents used to remove lubricant from our components. We asked one of our suppliers to perform a number of trials on different components using a variety of solvents and surface cleanliness tests clearly showed that modified alcohol was the most effective solvent for this purpose.
With the addition of trichloroethylene to Annex 14 of REACH (Registration, Evaluation, Authorisation and Restriction of Chemicals) in February 2013 as a Substance of Very High Concern (SVHC) the search for long term variable alternatives continues to gather pace. The industry trend is to move away from using chlorinated hydrocarbons for metal degreasing and modified alcohols offer an excellent substitute, significantly reducing solvent consumption.
With growing demands for industry to reduce wastage rates and energy consumption for both economic and environmental reasons, an increasing number of manufacturers are looking to adopt more efficient and sustainable production methods and for those engineering companies that are aware of, and open to, current technologies there are some powerful options available.
About Dawson Shanahan:
With over 60 years experience, Dawson Shanahan Limited is a leading global specialist offering complete solutions in cold forming and machining of high precision, customer specified copper, aluminium, ferrous and assembled components. The company’s products meet the demands of a wide range of sectors including aerospace, automotive, electronics, laser, medical, packaging, plasma, power distribution, telecoms and welding.