Lighter, faster, more precise
Modern materials, lightweight components or even more efficient and highly productive manufacturing: In many industries these keywords indicate a permanent challenge for production planners and designers. The advantages of rotary swaging also apply perfectly in this case. Rotary-swaged components are lighter, highly accurate and produced faster than is possible in comparison to cutting procedures. We have summarized the advantage of this process in six main areas.
Advantages and characteristics
Rotary swaging gives designers a great degree of design freedom. The range of possible shapes is larger than with other forming processes. In the case of tubes, this applies to both the inside and outside diameter. Even complex internal profiles, splines and sophisticated geometries are produced ready for installation.
With many applications, rotary swaged components made from tubes can replace solids parts that have previously been used. This significantly reduces the weight of the components. The process also stands for greater economic efficiency: There is no build up of swarf, the volume of the blank is already the same as that of the formed component (see Table 1). A great deal of material is hereby saved during production. Complex components can therefore also be produced economically, whereas their shape would make it difficult to use blank tubes in other processes.
Workpieces can be formed to the final shape by rotary swaging. The tolerances on the outside diameters are between 0.01 and 0.1 millimeters. This corresponds more or less to classification 8 to 9 of the ISO tolerance (IT) (see Table 2). The accuracy improves as the diameter is reduced. In the forming of inside diameters over a mandrel, tolerances of less than 0.03 millimeters are achieved. The precision depends on the process used – recess swaging or infeed swaging – and the cycle times during forming. Generally, rotary swaged surfaces show very little surface roughness and a high proportion of the surface will be load carrying. There is practically no indentation effect. Mean values of 1.0 micrometer Ra for infeed swaging and 0.1 micrometers for recess swaging are normal. The surface quality achievable is equivalent to skim pass turning.
During cold forming, the workpiece becomes harder and in many ways, more stable – distributed almost evenly over the entire cross section of the workpiece. The yield strength which is generally crucial to the strength interpretation of mechanical parts is hereby increased significantly more through cold forming than the tensile strength of the formed component (see Table 3). Rotary swaging can also achieve greater degrees of deformation as compared with many other solid cold forming processes. Reductions in cross section of up to 90 percent without intermediate annealing are achievable. This also means: the process chain is significantly slimmed down.
Ready for installation
Producing workpieces that are ready for installation or nearly ready for installation. When manufacturing precise components, only slight turning operations are generally required. If desired, these and other Felss operations can also be integrated into the transfer lines (axial forming, thread forming and rolling, punching, milling, measuring /testing, etc.).
In principle, all materials that can be formed are suitable for rotary swaging. Even sintered materials can be compressed in this way. The elongation at fracture A5 should however be at least five to ten percent. Non-alloyed steel is suitable for steel materials as are low and high alloy steels. Non-ferrous metals such as aluminum, copper, brass, bronze, titanium and their alloys can also be formed without problems.