Whether in radiators or catalytic converters – knitted wire fabric is used frequently in modern automobiles. DHD Technology, a leading company in the process and environmental engineering sector based in Spalt near Nuremberg, Germany, supports its partners in the automotive and automotive suppliers industry with many years of experience. The tailored solutions range from filtration to storage and insulation.
The innovative fabrics from DHD Technology can contain up to 5 strands – smooth or wavy. The diversity of knitted materials comprises steel, various stainless steels and copper. Monel®, plastic monofilament, multifilaments, aluminium, glass and carbon can also be processed, however. Wires with diameters from 0.03 to 1.0 mm are knitted.
The special knitting machines, which are sometimes manufactured in-house, have special requirements where stitch forming is concerned. With very fine wires, tearing of the wires has to be avoided and an optimal stitch has to be formed. With extremely thick wires the situation is different: enormous forces are generated here which have to be absorbed.
Knitting machine needles by Groz-Beckert impressively fulfil these tasks. In many years of cooperation with DHD Technology, precisely coordinated needle and hook shapes have been developed. With their geometry these guarantee long service life even under the toughest of conditions.
For thick wires, for instance, needles of the type Lehal 81.230 G 01 are used, while type De 76.90 G 01 from the extensive Groz-Beckert portfolio is used for fine wires.
“With these products we are ideally positioned, and with Groz-Beckert we have a partner who represents expert consulting and a keen understanding of details,” says CEO Dieter Heubusch.
Sample automotive mesh applications
1.Knitted wire mesh filter and cooler for the gas generator in the airbag
2.Acoustic and shielding technology
3.Oil mist separators for the valve hood
4.Sliding seat rings and catalytic converter bearings for exhaust systems
5.Decoupling elements for the heat shield
6.Vibration dampers for the engine and exhaust area
Thoroughly effective insulation plays an important role in automotive longevity. In contrast to conventional materials, sealing cords made from knitted wire fabric or fibreglass have far higher temperature resistance. As a result, certain combinations of materials have proven themselves for many years now. Whether fully knitted, hollow-knit or with fibreglass sheathing, sealing cords resist temperatures of up to 1,100° C reliably and long-lastingly.
Moreover, knitted wire fabric performs important services in the automotive industry even before the complete vehicle is delivered. Knitted wire fabric and formed parts made from high-quality stainless-steel wire are used for the efficient storage and protection of sensitive and highly-priced components such as catalytic converters and exhaust systems.
Diversity in filtration
Interior air filters, oil mist separators, fuel filters, particulate filters… The environmentally compatible separation of oil/water mixtures is yet another example of filter application diversity inside a car. Filters are even employed in airbag systems. Knitted filters made from wire or composites function highly effectively here. Alongside the development and production of suitable knitted wire fabric here, DHD Technology also offers industrial parts cleaning and residual contamination analysis among its services.
Industrial parts cleaning
Knitted wire fabric only achieves its full effectiveness when in optimal condition. In view of the importance of sustainability, any dirt or contamination needs to be professionally cleaned away. For years now DHD Technology has provided a method for just this: the full vacuum plant using perchlorethylene cleans cheaply and effectively, and can be specially adapted to individual requirements. Both the mechanical engineering and automotive industries make use of this industrial parts cleaning method.
Far-reaching residual contamination analysis
By means of targeted residual contamination analysis, DHD Technology detects the amount and the quality of substances adhering to the surface of a structural component that can be removed with the prescribed solvents and cleaning techniques. The company makes use of diverse technologies in this regard:
In the so-called flushing cabinet, which contains up to three membranes, components can be cleaned by spraying, ultrasound, flushing and flooding. Here DHD Technology fulfils not only the requirements of norms ISO 16232 and VDA Band 19, but also the factory norms of its international customers.
After cleaning, gravimetrical evaluation takes place with an accuracy of 0.01 mg.
In light microscopy, the number and size of the detected particles are analysed. A differentiation is made between metals, fibres and non-metals. Working together with DHD Technology, Groz-Beckert is proud of being a part of the supply chain for innovative automobiles of the latest generation.