Executive Q&A: Danfoss’ Tony Welter on the future of hydrostatic drives

Launched in 2005, Danfoss Power Solutions’ H1P axial piston pump – which is said to have pioneered the closed-circuit variable displacement axial piston pump category – continues to serve as a flagship product for the company.

Tony Welter, president, Hydrostatics Division, Danfoss Power Solutions. (Photo: Danfoss Power Solutions)

Yet, even as the H1P has continued to endure, the shift to electrification has some wondering how long hydrostatic drives may ultimately last and the role products such as axial piston pumps will play in the years to come.

The Power Briefing editorial team reached out to Tony Welter, president, Hydrostatics Division, Danfoss Power Solutions, to gain his insights on this topic, as well as the history behind and future of the iconic H1P.

PB: With electrification growing, are hydrostatic drives — long a cornerstone in mobile equipment — at risk of being phased out, or will their role evolve?

Hydrostatic drives will not be phased out. We see a long, bright future ahead for our portfolio and the market in general.

The products will — and have — evolved. For example, we’re adding new products to our H1 high-power platform and MP1 medium-power platforms, and we’re continuously developing new control options and new features. Hydrostatics are still winning new applications, such as tractors, wheel loaders and telehandlers, where OEMs are rolling out new machine sizes and platforms. So, we still see hydrostatics as a growth market overall.

Electric drives are making inroads in some traditional hydrostatic applications, such as aerial work platforms, but the value proposition is different. There are some markets and applications in which electrics are a better fit than hydrostatics, but both have their place.

PB: What applications do you believe will continue to rely on hydrostatic transmissions over the next decade? What makes them irreplaceable in those applications?

Hydrostatic transmissions will remain dominant in applications requiring high power density, robustness and reliability. Today, those applications include compact track loaders, skid-steer loaders, wheel loaders, tractors and the like.

Those applications could change in the next decade, but what won’t change are the capabilities hydrostatics provide: the ability to deliver a lot of power from a compact package, withstand environmental extremes with ease and offer smooth performance and durability in very dynamic loading situations, meaning constant forward-backward, start-stop motions.

PB: Before debuting the H1P in 2005, what challenges or trends was Danfoss responding to at the time? What made the H1P a standout solution?

H1P addressed several trends. The first is space constraints. Our customers wanted a more power dense solution to fit into increasingly crowded engine compartments. In general, H1 was more compact and power dense than alternatives at the time.

The H1P remains a flagship product for Danfoss due to its efficiency, compact and lightweight design and precise control. (Photo: Danfoss Power Solutions)

The second trend is electronic control. Our customers were interested in transitioning away from manual controls, so we wanted to develop a solution that enabled more functionality and more options than we had historically.

Third, we wanted to enhance the performance of the pump, primarily in efficiency.

And finally, with the increasing globalization in machine development, we wanted to design a product with common interfaces and controls.

The H1P was a standout solution and remains our flagship product today because of its high efficiency, compact and lightweight design and precise control. These features enable safe, predictable machine operation while reducing total cost of ownership.

PB: After 20 years and 1.7 million units sold, what has kept the H1P design relevant in a dynamic market? What have you learned from its long production run?

Those value propositions I previously mentioned are the first part of H1P’s enduring relevance. The second part is that our control strategy anticipated market needs.

As machines have become smarter, more customizable, and increasingly electronically controlled, we have been able to evolve the pump’s controls design and performance. We’ve developed new control options with no change to the pump’s hardware. We’ve also changed some hardware options that have enabled additional functionality and features.

Customers value the quality and innovation we bring to the table, but there’s more to it than great products. Partnering with them over the years has helped us to define value not only in the product, but at the machine solution level and in day-to-day operations. Over 20 years, we’ve developed a level of familiarity and flexibility with our customers that they really value.

PB: What does the recently introduced 180cc H1P with ECO Mode and PLUS+1 compliance tell us about where the platform is headed? More broadly, what does it say about the future of hydrostatic technology?

We have multiple displacements in our H1P product line, and the 180cc pump fills a gap we had in the line. As platforms have evolved, the 180cc displacement is now more of a sweet spot in terms of market volumes. Sure, we could specify a larger pump for those applications, and that has been done in the past. But today it’s important to offer the right-sized product to drive the most efficient, effective performance in the application.

Hydrostatic transmissions will remain dominant in applications that require high power density, robustness and reliability. (Photo: Danfoss Power Solutions)

As for what it says about the future of hydrostatic technology, at Danfoss, we’re bullish that there are still growth opportunities. Furthermore, OEMs want options and flexibility in the products they apply. Products enable a solution, and we want to be a full solution provider.

Control modes, like our ECO Mode, are one example that mirrors what we see in cars today, offering flexibility and configurability to drive optimal performance in different operational conditions. It also reflects the changing dynamics of the workforce. Providing different modes of control enables the right machine configuration tuned for the specific operator for the specific task.

PB: Should OEMs expect a fourth-generation H1P in the future, or are you more focused on incremental innovation within the H1 family?

Danfoss continually invests in new technology and innovation in hydrostatics. We have some really interesting things on the horizon, but we’re not ready to talk about them just yet.

What I can say is the trends we discussed around power density, efficiency and controls will remain focus areas for us as we strive to push the envelope. We have a full pipeline of innovative ideas that we look forward to launching on the market.

PB: As machines become more integrated by blending hydraulics, electronics and software, how is Danfoss positioning the hydrostatics division to stay ahead of the curve?

Our solutions are technology agnostic. Danfoss will provide the best solution for the market need.

For example, we’ve partnered with companies to design transmissions that can use hydrostatics or electric solutions interchangeably. That architecture enables OEMs to offer flexibility to their end markets.

Our Editron division is taking advantage of the shift to electric drives in aerial work platforms with their low-voltage system solutions.

Whether electrics or hydraulics are the right fit, Danfoss has a solution. Within our Hydrostatics division, we’re keeping an eye on platform evolution, especially the shift from internal combustion engines to batteries. We’re looking at our architecture to determine how we might better serve battery-electric vehicles and whether other architectures could be more beneficial for our customers.

And, of course, we’re always exploring new and different applications beyond traditional propel systems to ensure continued industry leadership.