Together with the wire rope manufacturer Teufelberger, Liebherr is developing a new type of high-strength fiber rope which will replace wire ropes for various applications.
The new climatic chamber in Biberach an der Riss (Southern Germany): temperatures can be as high as 176°F (80°C) here, or as low as 41°F (5°C) below freezing point. Sand or dust may swirl through the air to simulate conditions on a construction site in the desert. A moment later, monsoon-style rainfall sets in.
This is where a team led by Dr. Ilaka Mupende, Research and Experimental Manager at Liebherr-Components Biberach GmbH, is testing a high-strength synthetic-fiber rope for use on cranes. “The rope is extremely light but nevertheless very strong. It has the same load capacity as a steel rope and spools up excellently. Although the prestress is low in the lower rope layers, the rope is scarcely subject to any wear when several layers are spooled onto the drum.”
This innovative product is being tested under extreme weather conditions as well as different load patterns. Together with his team Dr. Mupende is subjecting each prototype of the new rope to thorough testing on various fixtures for at least three months.
For Ilaka Mupende, the rope is only one element in the overall lifting gear, but a decisive one. “A high tower and a long jib may make the crane look highly spectacular, but without the rope the entire structure would be pointless. As I see it, the crane’s rope is just as essential as a human’s heart.”
“The rope’s weight can therefore be almost entirely disregarded as an operating factor,” says the 52-year-old. There is an enormous gain in rope operating life as well. “The fiber rope we have developed has an operating life ten times longer than a steel rope.” Translated into customer benefits, this means the rope must not be replaced so frequently.
During development work on the synthetic fiber rope, close attention was given to the correct spooling formation on the rope drum and to identifying the need for renewal when approaching the crucial rope wear limit. “A visual check on the outer sleeve of the fiber rope is all that’s needed,” says Dr. Mupende.
Ilaka Mupende remains fascinated by rope technology, and will press ahead with intensive research work until the high-strength fiber rope is ready for the market. An important aspect of his team’s work is identification of the wear limit. “Our aim in the next few years is to modify and optimize the rope to make it suitable for a variety of practical applications.”