Professor Chao Peng is investigating the wear of rubber seals at the Institute for Fluid Power Drives and Systems (ifas) at RWTH Aachen University.
Flexible and reliable under the right circumstances, rubber seals are found in almost all’heavy-duty machinery and hydraulic systems. They allow movement while preventing fluid leaks. In applications like excavators and car brakes, for example, they ensure proper functionality and contribute to system safety.
"A sealing ring might be a small component of a machine, but its failure can have a big impact," says Professor Chao Peng. Since September, he has been researching at the Institute for Fluid Power Drives and Systems (ifas) at RWTH Aachen University as a Humboldt Research Fellow. His expertise lies in the wear mechanisms of rubber seals in hydraulic systems. Through the Humboldt Research Fellowship, the Alexander von Humboldt Foundation supports outstanding researchers from around the world.
To improve the durability of rubber seals in fluid power applications, it is crucial to precisely measure material wear. Although there are models that simulate friction between rubber and counter surfaces to predict potential failures, Professor Peng emphasizes: "There is no model that comprehensively accounts for both lubrication and wear." The high pressure these seals often face leads to high friction, posing significant challenges.
Another challenge arises from the uneven surface of rubber and the complexity of tribological contact between the elastic seal material and the cylinder rod, making accurate wear predictions difficult. Previous work has shown that lubrication conditions significantly influence friction and sealing ability and largely depend on the machine’s environmental conditions.
To predict the service life of a rubber seal as accurately as possible, Professor Peng tests seals under various pressure conditions and temperatures ranging from -55 °C to 135 °C (or -67 °F to 275 °F). His experiments show that at a temperature of 80 °C (176 °F), for example, the seal begins to lose its function, leading to fluid leakage.
Chao Peng considers his research opportunity at RWTH Aachen University a great honor: "RWTH is a world leader in mechanical engineering, and I experience firsthand the impressively high level at which my colleagues work here every day," says the engineer. He adds that he was delighted to be given this opportunity to conduct research at RWTH. Professor Katharina Schmitz, Head of the Institute for Fluid Power Drives and Systems (ifas) and globally recognized expert in fluid power seal technologies, will be his host during his funding period.
