"The first email sounded quite harmless," recalls Hartmut Wandel, Managing Director of Neff Gewindetriebe GmbH. "It was an inquiry about torque and temperature range." A foreign company contacted Neff in April 2021 to solve a special task for the altitude level regulation of a research station - in Antarctica, where the average annual temperature is -55 °C!

Research activities on the southern continent include meteorology and climate, geosciences and glaciology as well as oceanography and marine biology. While temperatures on the coast even reach a few degrees above zero in January, the lowest temperature ever recorded in the wild was recorded in East Antarctica almost 40 years ago: -89 °C.

Technical challenges

A new building for a research station is currently under construction. It stands on glaciated ground that moves slowly. Added to this are precipitation and wind. To prevent the building from sinking over time, it has to be leveled. That is why it stands on 36 steel feet that can be adjusted using lifting gears.

The research station is located on the flat snow surface of the East Antarctic glacier plateau, above the largest subglacial lake on earth. It lies at an altitude of 3,488 m above sea level, approximately 1,250 km from the geographic South Pole. The thin air at this high altitude favors cooling: In the Antarctic winter, temperatures here can be as low as -80 °C. In this inhospitable environment, the technology has to withstand all weather conditions. Neff selected 36 size C100 linear actuators in a lifting cylinder design for the level control. They are height-adjustable over 900 mm and can lift loads of up to 100 tons each. However, there were other challenges in addition to the required force: The lifting speed had to be 30 mm/min. A reserve of 30 % above the nominal value was required for the torque. However, the greatest engineering achievement was to design these screw jacks for the extreme cold. "While materials down to -40 °C are specified in Europe, -80 °C was required for the southern continent of Antarctica," reports Neff Managing Director Wandel. "All attachments - the geared motor, electrical sensors for temperature monitoring, sensors for stroke measurement and stroke limitation - must be able to withstand these adverse environmental conditions." The necessary lubrication and sealing of the entire system are also an unusual Herculean task.

Powerful drives

Neff sent an inquiry to SEW-Eurodrive, which sales engineer Markus Raff from the Stuttgart technical office dealt with. "Bevel gearboxes are particularly compact," he explains. "This feature is therefore of interest for applications with limited space, such as those in the stainless steel feet of the research station." Due to the extreme environmental conditions in the Antarctic, SEW-Eurodrive carried out strength calculations for housings, shafts and gear parts at -80 °C. Special surface and corrosion protection was selected as special measures for the extreme operating conditions. In addition, heating tapes and a special lubricant for the low temperatures were used. SEW-Eurodrive calculated the power loss for an ambient temperature of -35 °C in the Antarctic summer, at which the drives are operated. The gear oil, the sealing system, distortions and other criteria were taken into account. The Bruchsal-based drive specialist assured the customer of the torque and maximum speed values at the output of the geared motor. A total of 36 bevel geared motors from the KAF87 DRN160M4 series were selected as drives and adapted to the Neff lifting gearboxes using a special flange. With a rated output of 11 kW, these geared motors deliver a torque of 2,000 Nm under the specified boundary conditions.

Function test at -80 °C

In October 2021, Neff subjected a complete C100 lifting system to extensive testing at IABG in Ottobrunn, a testing service provider for the aerospace industry, to ensure that everything works under the extreme conditions in Antarctica. The lifting system was tested in a cold chamber at -80 °C with a static load of 100 tons. A dynamic test was then carried out with the same load at -35 °C. This corresponds to real conditions, as lifting movements are only carried out during the Arctic summer. This ensured that there were no negative surprises after delivery. Neff also supported its customer with the installation of the hoist gearbox in the steel base. At the company headquarters in Weil im Schönbuch, the installation was practiced together with the customer's fitters so that nothing was left to chance later in the Antarctic cold. The entire project was also under enormous time pressure because the gearboxes had to arrive on the southern continent before the start of summer, i.e. around the turn of the year. "It was a 'hot box'," recalls Hartmut Wandel.

Transport logistics to the South Pole

"Logistics was also a big issue," explains the Neff Managing Director. After a trial assembly, all the material was shipped to Antarctica. 36 crates with the screw jacks were transported by truck to Bremerhaven and loaded onto an icebreaker there. Once on the southern continent, 29 crawler tractors transported the equipment through the Antarctic ice desert day and night for two weeks. The Pistenbullys covered 1500 km in one direction. Due to the weather conditions, the station and drives can only be installed in the short time window during the Arctic summer months, i.e. between November and March. During this time, the average temperature is a "warm" -25 °C.

Cooperation based on trust

The Neff branch in Oberwang, Upper Austria, 35 km east of Salzburg, was in charge of the technical solution. Its manager Martin Kirchmaier recalls: "The first emails and video meetings with the business partners' managers were characterized by cautious restraint. Over the course of the project, however, a dynamic developed with the strong will to deliver the lifting elements with the required technical performance, cold-tested and on the agreed date. It became a flow with our team, but also with our suppliers." Neff Managing Director Hartmut Wandel adds: "What drives us is always the idea of moving things forward with our customers. We offer engineering services made in Austria and Germany and implement solutions for complex drive technology problems. We rely on resource-saving materials and durable products that can still be repaired decades later."

A major advantage for Neff and the end customer is that the customer advisors at SEW-Eurodrive always take comprehensive care of the projects. This greatly simplifies project coordination. What's more, Markus Raff originally comes from the same place as Neff Gewindetriebe GmbH. He remembers: "When I was young, I did an internship at Neff and later worked there as a vacation helper." Since then, he has had good contact with Neff, which he now supports in SEW sales. And David Bohny, Market Manager for gear units, adds: "As you can see from this particular application, SEW-Eurodrive is very flexible in responding to customer requests. With the experience gained from a large number of different projects, we can develop customer-specific solutions in a short space of time. The geared motors are assembled using standardized processes to ensure product quality. Finally, the logistics processes enable fast and reliable delivery - worldwide! "

Gunthart Mau, Press Officer at SEW-Eurodrive, Bruchsal