With nearly 10,000 employees, 50 foreign subsidiaries and more than 500 sales and service partners, HYDAC International GmbH, based in Sulzbach, Germany, is one of the world's leading fluid technology companies. The product range extends from individual components and subsystems to complex, open-loop and closed-loop drive units for mobile and stationary machines and systems. HYDAC also offers its customers a comprehensive package of technical services in fluid engineering for media such as hydraulic oils, lubricants, cooling lubricants and water. Contemporary topics such as predictive maintenance, condition monitoring, e-mobility, energy-efficient hydraulics as well as process transparency, electrification and function integration are currently dominating developments. The Saarland company is also involved in the promising hydrogen solutions segment. In the run-up to the upcoming HANNOVER MESSE 2023, HYDAC is addressing the design challenges of fuel cells with an innovative clamping band solution.

Fuel cell vs. battery solutions

Many experts now see fuel cells, some of which have already been written off, as the better alternative to battery solutions when it comes to mobile applications that require large amounts of energy and high performance over a long period of time, such as heavy-duty transport, buses, trains or ships. In combination with high-pressure hydrogen refueling systems, fuel cells offer an economically viable alternative for zero-emission driving and operation. For these fuel cell systems HYDAC develops specific solutions in fastening technology. In addition to the fastening of high-pressure tanks, innovative tension band solutions in the direct vicinity of the fuel cell are used above all.

Tensioning straps as a better solution

In contrast to fuel cell manufacturers who brace their fuel cell stacks with threaded rods, the Saarland-based company relies on circumferential tensioning straps. According to HYDAC, threaded rods have the disadvantage that they distribute the contact pressure unevenly, which means that optimum force distribution on the stack cannot be achieved. As a result, leaks could occur between the individual bipolar plates, which in turn leads to energy losses and poorer system efficiency of the fuel cells. Compared to conventional threaded rods, the HYDAC solution with tension bands has the advantage, among other things, that the contact forces are applied much more evenly to the fuel cell seals. In addition, the tensioning band solution can reduce the weight of the fuel cell stack, optimize installation dimensions and simplify the assembly and maintenance process.