Innovating Across Decades: A Technology Ahead of Its Time

As ETP Transmissions celebrates 40 years as a company, the innovation that took the company out of the starting blocks is still as relevant as ever. The first hydraulic hub-shaft connection, long known as the “ETP-CLASSIC”, was sold in 1973 – more than ten years before the company saw the light of day. With a groundbreaking design, built on hydraulic principles, it came to shape the subsequent journey for the corporation.
– We like to say that Pascal came up with the idea and we put it to work. And, luckily, the industries were as enthusiastic as we were, Niclas Rosberg, CEO at ETP Transmissions, says.

In the early 1970s, the advent of advanced manufacturing machinery prompted a surge in demand for innovative hub-shaft connections suited for the new era of power transmission. While inventors in other parts of Europe focused on mechanical transmissions, the Swedish entrepreneur Kjell Landeaus had a different, in many ways more innovative, approach. Inspired by the principles of the renowned French mathematician Blaise Pascal, he engineered a product that in large consists of hardened double-walled steel sleeves welded together to create a hollow chamber that can be filled with a hydraulic pressure medium. By applying hydraulic pressure, the chamber expands uniformly against both the shaft and hub, ensuring a very accurate and rigid joint from which the power is transferred through friction – providing groundbreaking concentricity and repeatability. The original patent was developed for Försvarets Fabriksverk (a part of the Swedish Armed Forces), but soon the founders started to look for civil applications for the product and ten years later it became a cornerstone in the offering for the then newly formed company ETP Transmissions AB. Since then, the hub-shaft connection has come to be known as the ETP-CLASSIC and has been followed by many renditions aimed at different segments of the manufacturing industry.

“We recognized the greatness of using the hydraulic principles and saw an opportunity to build a company around the concept. Until then, the industry had not seen the kind of precision for hub-shaft connections that we could provide – especially not in combination with how reliable the couplings are over time. To ensure minimal leaks, we developed our own type of 'clay' where the viscosity makes it much harder for it to escape the structure compared to other mediums”, Niclas Rosberg says before adding:

“Our hub-shaft connections are more expensive than those based on mechanical joints, but when those working in the industry have had the chance to try our solution, there's rarely any discussion about which they prefer. Especially these days when we have made the couplings incredibly easy to attach.”

Kent Månsson, Börje Peterson and Anders Samelius showing the first hydraulic sleeves from ETP.