WCA September 2013

Flat wire for high-performance springs

strength across the entire cross-section. In addition a stable supply-chain with a broad set of machines is recommended, that can ensure both small quantities for validation purposes and larger annual contacts with partial deliveries and accurately maintained tolerances. Studer SA – Switzerland Website : www.studersa.com For extremes As oil and gas producers push their technology to ever-greater ocean depths to find sources of supply, there has been an increased need for long-distance, high-temperature and high-pressure sensors and communications devices. Ametek SCP has developed the technology to produce a glass-sealed fibre optic feedthru (FOFT) for extreme high-pressure, high temperature appli- cations. Ametek SCP – USA Website : www.ametek.com

providers work in the range of 1:2 to 1:10. Depending on the required applications, such a flat wire has: • natural edges In the small to mid-latitudes thickness ratio natural edges provide an economical solution. Rounded edges, ie edges that go through a peeling process after cold rolling, offer an even closer and more regular width tolerance, especially for high quality products with very tight bending radii. Rolled edges are formed by a vertical pair of rollers. This manufacturing step shows width tolerances similarly tight as rounded edges. Defined radii allow very tight customer specific requirements to be obtained. Compared to steel strip, cold-rolled flat wire has the advantage of very large lengths without welds (wire up to 500kg per coil) and a homogeneous spread of • rounded edges • rolled edges or • defined radii.

Today’s technical applications call more and more for springs with a compact design combined with high spring forces. In addition, due to highly automated manufacturing processes, often tight dimensional tolerances are requested. Whether in the automotive sector, precision engineering or medical technology, textile machinery or electrical connection technology, a high resistance to corrosion is often needed. For such applications, stainless-steel flat wire is commonly used – both traditional materials, such as AISI 300 and 400 series as well as special alloys. Specialised suppliers are even able to offer almost all cold-formable materials, whose procurement is possible. Flat wire is available in industrial quantities from widths of about 0.05mm, with a tolerance of ±0.005mm. Thicknesses start from about 0.02mm (20 micron) and tolerances of less than ±0.001 are possible. Some specialised companies in this field achieve width-thickness ratios of up to 1:50, and even up to 1:70, while the majority of

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Wire & Cable ASIA – September/October 2013