Today, more than 50% of the nearly 7 billion people on our planet live in cities. The FAO (Food and Agricultural Organisation of the United Nations) estimates that the total population will rise to some 9.2 billion by 2050, with the corresponding share of urban residents likely to be more than 75%.
These people will need to be provided with natural resources, energy, water and food, as well as having the ‘waste streams’ they produce — and the associated manufacturing waste — recycled by the most efficient means possible. The associated need for machinery, steel construction and transport means consuming limited resources at an ever-increasing rate, making it necessary to produce and use these resources in a sustainable, efficient and environment-friendly manner.
The German group EWM (
www.ewm-group.com) has developed Blue Evolution — a guide to making welding processes significantly more efficient and minimising their environmental impact. An example of this is the high-performance welding process Force Arc, which EWM developed because it believes that just determining the characteristics and configurations of a welding process is not enough. “It is a matter of developing new processes that are specifically adapted to the welding task,” says the company.
Core expertise
Drawing on their expertise in the areas of electronics, microprocessor technology and inverter technology, the engineers and technicians at EWM analysed the complex interactions between the various components and parameters, allowing them to optimise the entire welding process — and break the ‘established welding code’. One of the characteristic traits of Force Arc is a heat-minimising, directionally stable and powerful arc.
The associated highly dynamic current control also provides for a large penetration depth with fewer under-cuts, providing advantages that include: material and labour cost savings; lower electricity costs; less preparatory work and finishing requirements; and improved working conditions as a result of a reduction in weld-fume emissions. Moreover, Force Arc increases a company’s competitiveness — and it can be applied to both manual and automated welding.
In Siemens’ locomotive manufacturing plant in the Allach quarter of Munich, locomotives have been produced for international markets for 170 years. For welding engineer Richard Beitinger, head of manufacturing, the most important thing with regard to welding the different components and assemblies is maintaining the highest quality standards. At the 2011 DVS Expo in Hamburg, Mr Beitinger met EWM welding expert Dieter Kocab, who was making a presentation on Perfect Welding Technology — a Glimpse of the Future. Siemens subsequently arranged for EWM to make a presentation on innovative welding processes; this was followed by a visit to EWM by Siemens employees.
Locomotive welding
As a result, Siemens started using EWM’s Force Arc process in 2012 at its Australian plant to weld locomotives used for heavy-duty coal transport. The conversion to this process was completed in just three months; after a year of practical experience with it, the company was able to say that its expectations had been fulfilled. Siemens works with various joining processes. For black steel, it uses either manual or robot-assisted MAG welding, whereas the joining of aluminium or stainless-steel parts is accomplished using MIG or TIG welding.
Mr Beitinger says the main advantage of the Force Arc process is the significantly decreased welding distortion that results from the substantially reduced heat input. Also beneficial are the reduction in time required for weld seam preparation, the smaller number of welding passes required and the substantially shortened welding times (not only making it possible to manufacture components more quickly but also giving Siemens more flexibility with regard to production and production planning).
In conclusion, Mr Beitinger says: “Innovative arc welding processes offer the potential of substantial savings for a low investment. Today, most manufacturers of welding power sources offer innovative arc technologies, but just switching to different characteristics alone is not enough. When implementing new welding processes, focusing on the many details and thorough training of the welders is decisive. A further prerequisite for the quick and successful conversion of welding processes and welding construction design is that all key players are involved in the project right from the start — including a nearby experienced partner of the welding-system manufacturer.”