Water-cooled electronics: Always stay cool – and dry
Power loss occurs in semiconductor elements, based on the operating point, and results in heat. The temperature must not exceed a specified value that is dependent on the semiconductor used. However, the relatively small surface of the housing can dissipate only a limited amount of heat, which necessitates the use of suitable heat sinks. The company austerlitz electronic gmbh specialises in such special cooling systems, which are equipped with connection technology from Eisele to ensure highly reliably seals.
austerlitz electronic gmbh was founded in 1968 as a subsidiary of Austerlitz Werksvertriebe, a distributor of electro-acoustic components since 1951. The company founder Alfred Austerlitz was one of the first entrepreneurs in Germany to recognise the demand for cooling systems for semiconductors. The company’s huge success soon necessitated a separate factory for the special cooling systems, which was built in 1971 in Henfenfeld near Nuremberg.
Today, the Austerlitz portfolio also includes media and communication solutions, connection and antenna technology as well as CNC and anodizing treatment, but the main focus remains on the innovative cooling systems, which are generally custom designed and manufactured by the company’s experts. “For all applications of our international customers that generate high power and high heat we develop highly efficient custom-
tailored semiconductor heat sinks,” explains Thomas Banz, Marketing Director at austerlitz electronic gmbh. “And we support our customers from the first contact all the way through to series production, all from a single source.”
A case for an expert
A main focus of production at austerlitz is on liquid heat sinks. This technology is gaining ground in the semiconductor industry, because the chips cannot always be cooled sufficiently by means of forced air. “However, the area of application for these liquid heat sinks is very diverse,” says Thomas Banz. “They are also used for cooling components such as diodes or capacitors, as well as entire assemblies.” The design of a liquid cooling system is more complex than that of an air-cooled system: it generally consists of a pump, a fluid tank and a heat exchanger, to dissipate the absorbed energy into the environment.
No less important is suitable connection technology for connection of the cooling systems to the supply and discharge lines. For the past 15 years austerlitz has relied on connection components from Eisele – and for good reason, because this application is very clearly a case for an expert: “After all, water and electronics must always be separated,” explains Thomas Maier, Managing Director of Eisele Pneumatics GmbH & Co. KG. “And that means that these systems require connection technology with absolutely reliable seals.” Also indispensable are good resistance to pressure and heat, as well as high flow rates; and the technology used must also be resistant to aggressive aqueous media and solvents.
A special product line for liquid cooling systems
No problem for Eisele: the company developed a special product line to meet the special requirements of closed liquid cooling systems. The LIQUIDLINE consists of different connector types and sizes, as well as a suitable selection of compatible hoses. Of course, all of the components are designed for excellent sealing: “So much expertise went into this development that certain connectors of the LIQUIDLINE can even be used directly in the control cabinet or in the cleanroom,” Thomas Maier explains. “We rely on connection technology used for example for leak detection in such demanding products as cardiac catheters.”
The components used by austerlitz from this line include straight threaded connectors as well as swivelling elbow connectors of the 2400 and 2600 series. The latter feature high-quality seals made of FPM (Viton) – all sealing points on the hose, threads and housing are designed for a life-long seal. The swivelling elbow connectors of the 2400 series are even equipped with two seals and are designed for pressures up to 24 bar. The components are manufactured from dezincification resistant brass – an alloy developed especially for closed liquid cooling circuits. LIQUIDLINE connections are resistant to high temperatures, aggressive aqueous media and many other substances. Another advantage: they can easily be connected and disconnected without the use of tools.
Aluminium instead of brass
Some of the austerlitz liquid heat sinks are equipped with an aluminium cooling channel, which requires a new approach to the connection technology. “Liquid coolers are often made of aluminium due to the high thermal conductivity of the material and generally remain in service for several years,” Thomas Maier relates. “In these cases, however, aluminium connections are also necessary to prevent electrolytic corrosion of the aluminium cooler.” This is the exact reason why the 2500 series of Eisele’s LIQUIDLINE also includes push-in connectors made of corrosion-proof aluminium – just the right product for austerlitz, as Thomas Banz confirms: “In the extensive assortment from Eisele we really always find the right solution. And we are also very pleased about the large number of individual connection options and capacity diameters.”
For the aluminium liquid heat sinks austerlitz chose the straight and swivelling elbow connectors. The customers benefit from optimal reliability: the threaded fittings of the 2500 series are ideal for motion-intensive applications requiring solid connections with maximum holding power or for applications with increased strain on the hoses. The reliability of the hose connections also pays off in the case of high pressure fluctuations. For the material, Eisele uses the special corrosion-proof EN AW-AlSi1MgMn. Conventional aluminium alloys such as AlCuBiPb cannot achieve the desired water resistance, which is why the manufacturers of liquid coolers are also increasingly switching to the new material, since it offers good protection against seawater and excellent protection against environmental influences. In terms of corrosion resistance, AlCuBiPb is satisfactory, while EN AW-AlSi1MgMn achieves good to excellent ratings in this respect.
Eisele Pneumatics GmbH + Co. KG
Hermann-Hess-Straße 14-16 | 71332 Waiblingen | Germany
Tel. +49 7151 1719-0 | Fax +49 7151-1719-17
