At Bauma 2022, Liebherr presents the new generation of concrete mixing plants, which replaces several predecessor series at once. Jürgen Forster, production manager for mixing plants, and Henrik Utoft, Team leader loading and shipping, explain the advantages and functionality of the new modular concrete mixing plant in this interview.
Mr. Forster, the new plant platform is technically and conceptually different from the predecessor model. What are the specific new developments?
Forster: “The new plant platform will replace several series at the beginning of next year. Our development focused on a modular design. This means that individual modules such as the mixer or scale module, but also the feeder module, can be planned, manufactured and combined with other modules or independently of each other. Several versions can be realised by choosing the appropriate support frame: Steel foundation for gravel foundation, steel foundation with a high degree of preassembly for an assembly optimisation on the construction site or the classic anchoring parts for the construction site assembly. The customer benefits from shorter delivery times, faster assembly and high parts availability. The customer is also more flexible in the configuration of the system.”
Utoft: “This modular system also has a number of advantages from a logistical point of view: Due to significantly more preassembled parts, fewer parts have to be manually packed and shipped. Another advantage is that we always have the same basic dimensions due to the modular design. This makes the planning of the vehicles easier.”
Impressive. This begs the question: Why did you make these innovations? Were there specific customer requirements?
Forster: “For us it was a mixture of customer requirements as well as our striving for optimisation and technical innovation of the system. With the innovation, we have reacted to the changed market situation. In particular, the rising costs and logistical challenges that require efficient and high-performance material supply and production played a role. On the other hand, we are responding even more explicitly to the wishes of our customers: Depending on the application, different mixer systems can now be installed with the same basic system.”
One technical innovation that immediately catches the eye of experts is the so-called ring-pan mixer with variable agitator speed. Could you briefly explain to laymen the principle and the development idea behind it?
Forster: “The ring-pan mixer is characterised by high mixing quality and high efficiency due to the agitator systems. With this ring-pan mixer, two powerful drives allow infinitely variable control of the main speed as well as the whirler speed. This creates the prerequisite for efficient and highly variable production of a wide variety of concrete types. Even highly complex concrete formulations for the precast industry are no problem with this mixer.”
With the help of a specific example: What advantages does the new series offer in a real-life application?
Utoft: “The modular design already plays a decisive role when setting up the new Betomix. The feeder lift is a concrete example: This can simply be “attached” to the respective concrete mixing plant, regardless of the plant output. Due to the vertical installation, up to 20 % less space is required for the entire plant.”
Forster: “In addition, the built-in frequency converter ensures more energy and resource efficiency. This offers the potential to reduce energy consumption by up to 30 %. With regard to the resource “cement”, the frequency converter works with an accuracy of +/- 0.5 %. To put it in concrete figures: for a typical recipe with 300 kg of cement per cubic metre of concrete, up to 7.5 kg of cement can be saved.”
Liebherr has already presented the plant platform at the Bauma media dialogue on 21 June 2022. How much development time did the innovations take and are there already first customers interested in the new concrete mixing plant?
Forster: “It took about two years from the first idea to the operational prototype. Currently, some projects are in the final phase, so that we expect the first orders by Bauma.”