Around 80,000 products leave the Aschaffenburg plant each year, where LHY Powertrain manufactures hydraulic drive systems for mobile machinery. Pumps, motors and valves are supplied to manufacturers of construction, agricultural, forestry and municipal machinery throughout Europe and worldwide. The unique selling point of the company – which emerged in 2012 from the hydraulics division of Linde’s forklift truck manufacturing business – is its wide range of variants: more than 100,000 product variants are manufactured in batches averaging 50 to 60 units. All core components, such as drive shafts, pistons, cylinder blocks and control pistons, are produced in-house, whilst key parts are sourced from the neighbouring Linde foundry. Thanks to this vertical integration and high quality standards, tolerances of two micrometres can be maintained in piston production. For quality control, all products are ultimately tested on one of the 14 test benches.

At the Nilkheim site, around 300 employees work in production, of whom approximately 130 are in the assembly department. “The assembly department is a key value-adding area of our company – and we are constantly working to further improve ergonomics, health and safety, and efficiency,” explains Rene Pfeifer, assembly planner in the Industrial Engineering Assembly & Testing department at LHY Powertrain.

The new generation of CPV pumps was the catalyst

The CPV series of hydraulic pumps provided the impetus for the new workplace design. The swash plate pump for closed-loop systems is available in eight nominal sizes ranging from 45 to 175 cm³/rev, operates at pressures of up to 500 bar and weighs between 50 and 110 kilograms, depending on the size. Its modular design allows for highly flexible configurations within a minimal installation space; between 130 and 140 individual parts are assembled per pump.

For the assembly process, this meant: numerous components, high variability, heavy weights and a complex assembly process. “We wanted to use this project to embark on the digitalisation of the assembly process,” explains Tobias Petermann. There were two further motivations: “We want to tackle the shortage of skilled workers and design the workplace in such a way that the operator is at the lowest possible risk of making mistakes. An operator guidance system provides instructions, requires confirmation – and makes incorrect operations highly unlikely.” Like Pfeifer, Petermann is an assembly planner in Industrial Engineering Assembly & Testing; together, the two of them led the project.

Six years of looking for a partner

Once the new pump series had been announced, Pfeifer and Petermann immediately set about looking for a supplier of a worker assistance system. Their search took around six years. “The market is confusing; there are many suppliers, including small firms and start-ups,” noted Pfeifer. “We chose Armbruster Engineering because they are a strong partner with a good track record. Their expertise in integrating with our SAP system was particularly important to us.”
As far as handling equipment was concerned, the choice of partner was a foregone conclusion: products from the ROEMHELD Group have been in use at LHY Powertrain for more than 25 years – ten lifting and swivelling modules are now in operation at the plant. The Aschaffenburg-based company also utilised machine vices and hydraulic clamping devices from the Hessian supplier’s range in its production, as well as press-fit devices in the assembly department.
“The fact that our modules were a given at LHY Powertrain right from the start gave us the opportunity to discuss the interfaces with Armbruster Engineering at a very early stage – and that was precisely what mattered in this project,” adds Peter Föhst, Area Manager at ROEMHELD.

Five stages, one continuous process

The CPV assembly line comprises five stations: four workstations for the pre-assembly of the actuator piston, control base mounting, adjustment unit and rotation assembly, as well as a main assembly station. This is where the four sub-assemblies are brought together. The cycle time for the main assembly is around 25 minutes. At the heart of this station is an electric moduhub handling system from ROEMHELD, comprising the Solid lifting module and the Strong rotary module. The electromechanical lifting module offers a stroke of between 200 and 600 millimetres with a lifting force of 4,000 N; the rotary module operates with a horizontal axis of rotation, a maximum torque of 500 Nm and a holding torque of up to 2,000 Nm. It can rotate continuously in both directions, is self-locking in any position, and its mechanical components are designed for 1,000,000 locking cycles.
Using a hand-held pushbutton for the lifting motion and a foot switch for the rotational movement, the fitter can effortlessly move the pumps – which weigh between 50 and 110 kilograms depending on the model – into the desired position, whilst keeping their hands free.
The decision to opt for an electric solution rather than a pneumatic or hydraulic one was a conscious one. “For us, precision, repeatability and integration into the digital operator guidance system were the top priorities,” emphasises Petermann. “Electric lift-and-rotate modules can be positioned precisely and integrated directly into the control system – added to this are the high reliability and low maintenance requirements that we are familiar with from other projects.”

At all five stations, the ELAM operator assistance system from Armbruster Engineering guides the process; between 60 and 80 work steps are programmed for each station, and depending on the variant, these add up to a total of 400 to 500 operations.

The operator guidance system takes charge

At all five stations, Armbruster Engineering’s ELAM operator assistance system guides the process; between 60 and 80 work steps are programmed for each station. “We develop bespoke solutions, and at LHY Powertrain we have between 400 and 500 work steps for the complete pump, depending on the variant,” explains Christoph Haase, project manager at Armbruster Engineering. LHY Powertrain’s work planning department categorised the assemblies and described the assembly steps; Armbruster Engineering implemented the plan and advised on which steps could be combined. “It was important to us to keep the number of changes to a minimum,” adds Pfeifer.
The key lies in the integration of handling technology and software: ELAM not only specifies the work step but also controls the position of the workpiece – the module rotates and lifts the pump into the optimum assembly position and clamps it in place for processing. To enable the handling system’s control unit to communicate with the workstation guidance system and, via this, with SAP, a sensor/actuator box is interposed, which in turn is controlled by the SWA – Smart Work Assistant from Armbruster Engineering. The company adapted this “ROEMHELD box”, which originated from an earlier joint project, to meet the requirements in Aschaffenburg. Also integrated are an RFID system for identifying the component size, scanners for reading the parts to be assembled, the control system for the assembly screwdrivers, a camera that compares 20 images per minute against stored templates, and a pressure tightness test.
“ELAM generates a product life cycle file,” emphasises Petermann. “Every step – checking, screwing, measuring, assembling – is not only specified but also precisely documented. This extends to details such as the torque at which a particular screw was tightened. In addition, there is a plausibility check to ensure that the components fit together.” Once a pump is complete, the workstation automatically reports this back to the SAP system.

The ELAM operator guidance system from Armbruster Engineering provides instructions, requires confirmation – and ensures correct operation in the specified sequence

Relief that makes a difference

In practice, the benefits are most evident where physical labour is involved: heavy components no longer need to be turned by hand, and the risk of workpieces falling is significantly reduced. “The biggest improvement relates to ergonomics and health and safety,” summarises Pfeifer. “At the same time, our colleagues are able to work more comfortably and quickly. Consequently, the system has been very well received.” CE compliance was achieved without difficulty, and the health and safety team also approved the workstation without any restrictions.
“Mechanical, electrical and control interfaces were jointly defined as early as the planning phase. This is why the lift-and-rotate module could be seamlessly integrated into the production line and the operator guidance system,” emphasises Haase. During the pilot phase, Armbruster Engineering was also able to adjust processes remotely from Bremen.

From pilot project to standard

By mid-2026, CPV assembly was in its ramp-up phase, initially producing 14 pumps per day in single-shift operation. The workstation is designed to produce around 50 units per day in three-shift operation, equating to approximately 10,000 CPV pumps per year. Deliveries to the first customers began right from the start – even though the workstation was technically still under construction.

“The pilot project went extremely well,” says Petermann. “Technically, there is nothing to prevent the results from being rolled out to other assembly workstations and production lines – that is precisely why we are laying the foundations here.” Pfeifer is also looking ahead: “We are consistently pursuing the goal of further digitising our assembly processes and improving their ergonomics. We can very well envisage working together with ROEMHELD and Armbruster Engineering again on future projects.”