Modern measuring system integrated into historic building fabric

Since the old measurement room now serves as an anteroom for the new facility, the height difference of half a floor, which exists between the two building sections, had to be bridged barrier-free. For this purpose, a hydraulic lifting platform was installed. Source: Nerling Systemräume GmbH

The new measurement room facility consists of a precision measurement room of Grade 2, a measurement room of Grade 3 for 3-coordinate measurement technology, and a material testing laboratory. These were roughly planned to allow the measuring machines to operate effectively. The intelligent lighting control via the built-in DALI system enhances this effect. Source: Nerling Systemräume GmbH

Since Bühler considered transparent design of the spaces very important, Nerling installed system rooms with full-glass walls reaching to the floor, with a height of 2.60 meters, used in this form for the first time. They allow visitors an unobstructed view into the measurement rooms. Source: Nerling Systemräume GmbH

For the testing and calibration of precision parts and measuring instruments, highly accurate measurements are necessary. These were carried out at the research facility of Bühler Motor GmbH, which manufactures mechatronic drive solutions for the automotive, industrial, and medical sectors, in outdated premises. To meet the high requirements even more precisely and with reliable reproducibility in the future, the company installed a modern, multi-part measurement room system that allows measurements of quality classes 2, 3, and 4 in separate rooms. To realize the project despite the location of the rooms on an exterior facade and insulation from the 1980s, Nerling Systemräume GmbH installed a system wall that acts as an insulator and thus creates the basic conditions for a uniform room climate. Since design and transparency of the new rooms also played a crucial role for Bühler, floor-to-ceiling glass walls and doors were integrated, providing visitors with an unobstructed view into the measurement rooms.

"One of the biggest problems of our old measurement room at the Nuremberg site was the lack of space," says Rainer Osterloh, Quality Manager Metrology at Bühler Motor and project manager for the new measurement room system. "There was also no division according to accuracy classes, and the office area was directly integrated." As the accuracy and reproducibility of measurement results also increase steadily in the manufacturing of drive solutions, Bühler Motor commissioned Nerling Systemräume GmbH to build a generously sized system: "A fine measurement room of quality class 2 was to be established, where, for example, ball bearings can be tested and measuring devices calibrated, as well as a class 3 measurement room for 3-coordinate measuring technology, and a test laboratory according to class 4, where hardness, coating thickness, and tension-compression forces on various materials can be examined," explains Olaf Nerling, managing director of Nerling Systemräume. Additionally, there should be a meeting corner and a separated larger office area for quality assurance. Bühler Motor specified the space requirements for individual machines and their assignment to the fine measurement or standard measurement room depending on their sensitivity. Based on this, Nerling Systemräume created a floor plan for the available area of a total of 36 meters in length and 11.40 meters in width.

Insulation concept ensures a uniform climate despite unfavorable room orientation

The challenge of the project was to achieve the required quality classes within the existing building fabric from the 1980s. Since the building insulation corresponded to standards of that time, Nerling installed a system wall in front of the actual building wall, which acts as an insulator. Without this measure, winter cold would have penetrated the room, and in summer, sunlight would have heated the air, leading to problems with the air conditioning system: "It is generally very unfavorable for a measurement room if it is placed on the exterior facade, as direct sunlight alone is enough to significantly disturb the room climate," says Nerling. Since exterior shading can only partially reduce this problem, corners would have formed where conditions differ from the rest of the room. The air conditioning system would also not have been able to compensate for this difference, as it only regulates based on a set value: "If temperature X is present in the room, air with temperature Y is blown in, and the system tries to distribute the air volume evenly to achieve the desired conditions," Nerling explains. "However, this does not balance out differing temperatures in the corners." By installing the insulating partition wall, the conditions are now met to create uniform conditions with the help of the air conditioning system.

The space created between the outer wall and the system wall can also be used as a technical area for noise or heat sources such as small pumps, PCs, and control cabinets: "All interfaces for power, air, and air conditioning are located in the narrow corridor," says Osterloh. "Maintenance and repair work can also be carried out there, so technicians no longer need to enter the fine measurement room." This reduces disturbances, and quality class 2 can be reliably maintained.

Simple load adjustment in air conditioning through individual units

Another challenge was that the ceiling height was only 3.35 meters, while the desired ceiling height in the measurement room was 2.85 meters. Nerling Systemräume installed individual units directly in the suspended ceiling, which achieved short air duct routes and thus low flow resistance and losses. Furthermore, the modular design allows the system to be expanded later without difficulty. "Typically, a central unit is installed in air conditioning systems, and only the ventilation ducts are laid in the ceiling," explains Nerling. "In case of expansion, the entire duct system must also be rebuilt." Additionally, once a central unit is purchased, it is fixed to a specific dimension that can no longer be changed. However, with the concept used at Bühler Motor, the room can be enlarged and adapted to higher loads, for example by installing two additional units in the ceiling. This also enables energy-efficient operation."

Since the old measurement room now serves as an anteroom for the new system, the height difference of half a floor between the two building parts had to be bridged barrier-free. For this purpose, a hydraulic lift with a one-ton payload was installed, where the room height also proved to be a challenge during assembly.

Transparent walls allow visitors insight into measurement rooms

Besides the building fabric and the location of the rooms, design was also a key consideration: "We are a research and development site, with renowned customers from the automotive and medical sectors coming and going," says project manager Osterloh. "Therefore, it was important to us to have an appealing and, above all, transparent design with a high glass content. We wanted to showcase one of the most beautiful measurement rooms in Germany." As a decisive design element, Nerling Systemräume used floor-to-ceiling full-glass walls with a height of 2.60 meters, which were used in this form for the first time. They allow visitors an unrestricted view into the measurement rooms without entering. Usually, the static design of such walls is difficult; in this case, installation was only possible because laminated safety glass was used, and the walls at Bühler Motor do not bear ceiling loads. Additionally, the doors were equipped with an electric drive that supports opening and automatic closing, preventing damage.

Comprehensive remote maintenance via PLC control

Since the system contains many rooms with high requirements not only regarding temperature stability but also humidity control, an elaborate and individual control system was necessary. Nerling Systemräume uses a freely programmable, central PLC control system. As part of remote maintenance by the measurement room builder, full access to all systems is possible. "In contrast to this holistic concept, conventional separate controls would only allow remote maintenance for the most important system," explains Nerling. An integrated 15-inch color display, embedded in a wall at a central location in the room system and showing all parameters, allows staff to quickly check, for example, the current temperature in any room and where the lights are switched on.

The measurement room system at Bühler Motor in Nuremberg has been operational since August 2011. "We are very satisfied both technically and in terms of design," confirms Osterloh. "Our temperature measurement results are very good, and the fine measurement room even reaches quality class 1 in a stabilized state." The entire system is also largely draft-free and very quiet, and the lighting is optimal: "We see the measurement room system as a long-term investment and are convinced that, based on the current values, we are well prepared for the future with this system," concludes the project manager.