Mobile and crawler cranes

4 minutes - magazine 01 | 2023

Why new oil for the superstructure gearboxes?

When we think about advances in crane construction, the first thing that comes to mind is longer booms, higher lifting capacities or more modern crane controls. But at Liebherr we also work continuously on improvements which are often invisible at first glance. Our objectives include higher quality, a longer service life, economy and greater comfort for you, the crane contractors and operators.

Currently we are looking at changing the gearbox oil for superstructure drive units. What we mean by this is the pump distributor gear, the slewing gear and the hoist winches as well as the travel drives on crawler cranes. Since a lot of departments must be involved to make such a massive project a success (design, documentation, purchasing, work preparation, production, testing, customer service and gearbox and oil suppliers), we asked representatives of some of these groups to explain.

On the assembly line - Information signs ensure that the correct gearbox oil is placed in the gearbox during the production process.

Modern and ready for the future

The new oil bears the name Liebherr Syntogear Plus 220 and replaces the existing Liebherr Gear PG 220. The new oil is more modern and ready for the future. It is a fully synthetic high performance PAO-based gearbox oil. Polyalphaolefin fluids are synthetic hydrocarbons which are designed to provide outstanding lubrication over a wide range of temperatures.

The oil is even suitable for cranes in countries with extremely low temperatures down to minus 40 degrees. That means that we can use the same oil for all temperature ranges throughout the world, which in turn means that we will not have to change any oil before delivery.

Liebherr Syntogear Plus 220 also delivers more positive features. It is more compatible with seals and paint and is less hygroscopic, which means it absorbs less water or water vapour from the ambient area.

Teamwork - We checked with representatives from several of the departments involved: (from left to right:) Patrick Strohm (Testing), Markus Bendt (Design), Christian Brunner (Production), Gerald Geisselhart (Design), Markus Kolb (Design), Manuel Letzgus (Production).

Around one half of crane models already switched

Such a massive change involving so many crane models requires a great deal of planning. We have tested that the new oil is not harmful to our drive units here at the plant and this has also been confirmed by external laboratories. The switch must be well documented and traceability must be guaranteed. That is also important for our customer service teams and crane contractors.

Everybody concerned must be provided with all the information they need to ensure that the right oil is placed in the vehicles. In fact, we receive many components from suppliers already filled. During the shipment assembly, the levels undergo a final check and are topped up with oil if necessary. We identify gearboxes which contain the new oil by information signs so that we can ensure that the correct oil is placed in the components throughout the entire production process.

Currently around half of our crane models are being supplied with the new gearbox oil. More models will follow gradually. It is also possible to switch cranes that have already been delivered to the new oil. But one thing you must take care not to do is to mix the different oil types. Contact our Customer Service. The team there will be able to provide you with instructions for switching to the new oil.

This article was published in the UpLoad magazine 01 | 2023.

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