Decisive factors in its specification were the material's compliance with stringent emission levels demanded by some of Germany's automotive OEMs for interior applications and its steel-like springiness. The material is also characterized by its vibration damping effect, its high notched impact strength and very good sliding properties.
The buffer-stop, injection-molded in Delrin® 100PE, takes up very little installation space with its 14 mm ´ 9 mm ´ 6 mm dimensions. Held by a rivet, it slides during adjustment of the steering column on metal guide rails until they reach their limit at the end of the adjustment range. Although the associated jolt may in some cases be hard, two small springs on either side of the buffer-stop are enough - thanks to the high stiffness and elasticity of the material - to cushion the impact both mechanically and acoustically. Moreover, as a direct benefit of the excellent sliding properties of Delrin® acetal resin, the buffer-stop will continue to move easily, softly and virtually inaudibly on the guide rails for the entire lifetime of the vehicle.
According to Ingo Weise, project buyer at ThyssenKrupp Presta: "Acetal is an established material for damping elements used in steering columns. At ThyssenKrupp Presta we have often used Delrin® 100P for similar parts in earlier designs where it met our requirements. In this particular case, however, we needed to meet especially strict emission levels. We therefore worked with DuPont on finding an alternative, including carrying out required testing. This ultimately resulted in us specifying Delrin® 100PE".
Martin Elmer, marketing manager for injection molding at Huber+Suhner, the Swiss-based supplier of the buffer-stops, adds: "We produce these high-precision parts, that are characterized by their variable wall thicknesses, in 16-cavity hot runner molds and keep within a tolerance of just ±0.05mm. Because the processing requirements of the new, low-emission Delrin® 100PE are almost identical to those of the 100P grade, we were able to adapt our production in the shortest of time and without compromising quality, all with the help of the experienced application technicians from DuPont".
Based on the direct and simple changeover in production, as well as the very positive experience to date during serial production, ThyssenKrupp Presta is planning to use Delrin® 100PE for further automotive applications of a similar nature.
The combination of high elasticity and stiffness as well as excellent sliding properties make Delrin® acetal homopolymers a material of choice for applications requiring low weight and where elements are required to absorb high forces, levels of deformation and impact, as well as to continuously move both smoothly and quietly. According to Hans-Hermann Kirner, material development leader for vehicle interiors at DuPont: "Gears and adjustment mechanisms are ideal applications for Delrin®. In view of the strict limits with regard to the emission of volatile particles, Delrin® 100PE is very suitable applications located within the vehicle’s interior. It is able to meet the demands of the global automotive industry with regard to emissions of volatile substances during both processing and use. The same applies to the higher flow grades Delrin® 300PE und 500PE. Tests conducted by SGS Institut Fresenius of Taunusstein, Germany, in accordance with VDA 275, revealed emissions of below 2 mg/kg for all three grades, whereas their strength, stiffness, impact resistance and resistance to creep and fatigue are the same as standard grades". DuPont has also recently introduced Delrin® 127UVE, 327UVE and 527UVE, which are all UV-stabilized versions of its low-emission acetal resin for automotive interior applications.
ThyssenKrupp Presta, Steering Division, is one of the world's largest producers of steering columns and steering systems, ranging from non-adjustable models to manually-operated height- and distance-adjustment systems for mid-class vehicles in Europe, America and Asia and electronically-adjustable models for top-range vehicles. At the end of 2007, the company gained a series production order for the supply of steering columns for the BMW 1, 3 and X3 series, as well as the development order for the steering control of other model ranges.
HUBER+SUHNER Gruppe, headquartered in Switzerland and with 24 companies and numerous authorised agents in over 60 countries around the world, is an internationally-leading supplier of components and systems for electrical and optical connectivity for the telecommunications, industrial applications and transportation industries.
DuPont Performance Polymers is committed to working with customers throughout the world to develop new products, components and systems that help reduce dependence on fossil fuels and protect people and the environment. With more than 40 manufacturing, development and research centers throughout the world, DuPont Performance Polymers uses the industry’s broadest portfolio of plastics, elastomers, renewably sourced polymers, filaments and high-performance parts and shapes to deliver cost-effective solutions to customers in aerospace, automotive, consumer, electrical, electronic, industrial, sporting goods and other diversified industries.
DuPont (NYSE: DD) has been bringing world-class science and engineering to the global marketplace in the form of innovative products, materials, and services since 1802. The company believes that by collaborating with customers, governments, NGOs, and thought leaders we can help find solutions to such global challenges as providing enough healthy food for people everywhere, decreasing dependence on fossil fuels, and protecting life and the environment. For additional information about DuPont and its commitment to inclusive innovation, please visit www.dupont.com.
The DuPont Oval, DuPontÔ, The miracles of scienceÔ and Delrin® are trademarks or registered trademarks of E.I. Du Pont de Nemours and Company or its affiliates.
This press release is based on information provided by:
ThyssenKrupp Presta, Steering Division
FL-9492 Eschen, Liechtenstein
Contact: Ingo Weise
CH-9100 Herisau, Schweiz
Contact: Martin Elmer
Tel.: +41 (0)22 717 54 19
Fax: +41 (0)22 580 22 45
Further Reports about: Buffer-stops > Delrin® > DuPont > fossil fuels > industrial application > low-emission > mechanically-adjustable steering columns > Performance Measurement-Systems > Polymere > steel-like springiness > Steering > ThyssenKrupp
More articles from Automotive Engineering:
Los Alamos catalyst could jumpstart e-cars, green energy
05.06.2013 | DOE/Los Alamos National Laboratory
New Speaker System for Cars Creates Separate “Audio Zones” for Front and Rear Seats
03.06.2013 | Acoustical Society of America (ASA)
... two engines aircraft project “Elektro E6”.
The countdown has been started for opening the gates again for the worldwide leading aviation and space event in Le Bourget, Paris from June 17th - 23rd, 2013.
EADCO & PC-Aero will present at the Paris Air Show in Hall H4 booth F-7 their new future aircraft and innovative project: ...
Siemens scientists have developed new kinds of ceramics in which they can embed transformers.
The new development allows power supply transformers to be reduced to one fifth of their current size so that the normally separate switched-mode power supply units of light-emitting diodes can be integrated into the module's heat sink.
The new technology was developed in cooperation with industrial and research partners who ...
Cheaper clean-energy technologies could be made possible thanks to a new discovery.
Led by Raymond Schaak, a professor of chemistry at Penn State University, research team members have found that an important chemical reaction that generates hydrogen from water is effectively triggered -- or catalyzed -- by a nanoparticle composed of nickel and phosphorus, two inexpensive elements that are abundant on Earth. ...
The Fraunhofer Institute for Laser Technology ILT generated a lot of interest at the LASER World of Photonics 2013 trade fair with its numerous industrial laser technology innovations.
Its highlights included beam sources and manufacturing processes for ultrashort laser pulses as well as ways to systematically optimize machining processes using computer simulations. There was even a specialist booth at the fair dedicated to the revolutionary technological potential of digital photonic production.
Now in its fortieth year, LASER World ...
It's not reruns of "The Jetsons", but researchers working at the National Institute of Standards and Technology (NIST) have developed a new microscopy technique that uses a process similar to how an old tube television produces a picture—cathodoluminescence—to image nanoscale features.
Combining the best features of optical and scanning electron microscopy, the fast, versatile, and high-resolution technique allows scientists to view surface and subsurface features potentially as small as 10 nanometers in size.
The new microscopy technique, described in the journal AIP Advances,* uses a beam of electrons to excite a specially ...
18.06.2013 | Materials Sciences
18.06.2013 | Health and Medicine
18.06.2013 | Life Sciences
14.06.2013 | Event News
13.06.2013 | Event News
10.06.2013 | Event News