Rotors for crushers must withstand the highest loads and require the precision of our KUKA welding robot

Lasaco has long relied on the advantages of automation for projects that require a high degree of precision and quality, which are only really brought to bear by the requirements and possibilities of Industry 4.0. In this project, a customer required high-quality welding equipment for the production of rotors, as used in so-called rock crushers or crushers. Such equipment is used to process minerals, metals, rocks and other materials that are similarly difficult to crush. The aim is often not only to crush the fragments, but also to separate different valuable materials so that they can be recycled or reused in other ways.

Why is a Kuka robot being used?

Welding rotors for such crushers is a complex process that requires a high degree of uniformity and stability. Otherwise, the rotors cannot withstand the forces that occur as desired. The tractors that power the rock crushers operate at up to 400 horsepower. The forces that have to be compensated by the rotors are correspondingly high. It is particularly important for the low-wear and reliable operation of the rotors that the teeth, which carry out the actual crushing process, are positioned with absolute precision. In addition, the welding must meet the highest quality standards and should therefore not exhibit any fluctuations, as can occur in manual production. In addition, the production of rotors is significantly faster due to the use of automated welding systems. These requirements are met by our KUKA robot, which not only delivers first-class weld seams, but can also repeat the production process any number of times with the same quality.

Kuka Robot KR16-2

Data sheet KR16-2

Lorch S8 RoboMig XT

RoboMIG data sheet

How does robotics help welding on an industrial scale?

Industrial manufacturing benefits in many areas from the use of robotics to automate welding tasks. In this case, a Kuka robot was used with Lorch S8 RoboMIG XT power source, which has the appropriate performance level for the customer's specific requirements. The actual welding is done by a Lorch MAG welder, which is precisely controlled by the robot according to the specified program. Lorch MAG products have proven to be particularly well suited for automation in manufacturing plants because they have been designed with interaction with robots in mind. As a result, the customer can not only produce his rotors for the crushers faster, but also rely on the consistently high manufacturing quality.

How does robotics help welding on an industrial scale?

Regardless of whether only one product is to be manufactured or variations in different designs are required: In order for the Kuka robot to know where and how to set the weld seams and spot welds, it naturally needs precise information about the workpieces to be processed. In the case of rotor production for stone crushers, adjustments to the program are always necessary because different rotors are used depending on requirements. Different lengths and diameters require corresponding program adjustments. For each new rotor, the necessary 3D data is created once, which provides exact information about the respective position of the teeth. After the robot has been fed this three-dimensional model, it can automatically calculate the position data for all weld seams and spot welds.

The robot does the manufacturing almost alone

Supplied with the existing data, the automatic welding system can position each component independently and specify the respective tooth positions. The human operator only has to tack the teeth there so that the robot can finish welding them on. If the system has a selection of different component sizes, these can be easily preselected at the control panel. This even makes the production of individual parts economically viable. The robot proceeds strictly according to a defined welding sequence, which helps avoid spot heating of components. Multi-layer welding ensures maximum strength of the joints. Another major advantage in the workflow is that tacking and welding are done in a single fixture without the need for reclamping. To ensure that this automatic production runs smoothly, Lasaco carries out a complete system maintenance once a year. Of course, our technical experts are also available to the customer at any time by telephone or - if necessary - on site to provide advice and assistance.


  • Position specification for tacking the teeth to be welded by the robot

  • Automatic calculation of all welding and intermediate positions

  • Rotor production in different lengths and diameters

  • Individual positioning of all teeth

  • Multi-layer welding

  • Definition of welding sequences in order to avoid spot heating of components

  • Tacking and welding in one fixture without reclamping