The German fashion retailer mister*lady relies on energy-efficient heating without dust and drafts. LK Metall installed an innovative heating and ventilation system as part of a new construction of a logistics center for the German fashion retailer mister*lady in Schwabach. An investment that has already proven itself in many ways, emphasizes mister*lady managing director, Rudolf Kempter.
Background: mister*lady GmbH moved its headquarters from Nuremberg to Schwabach. In addition to the new central administration with an area of 6,000 m², two logistics halls with an area of 4,500m² each were built. Each hall has 10 gates, a room height of about 7.50 m and a room volume of about 75,000 m³.
In particular, the climate-friendly heating and ventilation of the logistics halls posed a challenge. Managing Director Kempter was faced with a choice. “The architect, general contractor and other consultants recommended different solutions,” he recalls, “so with new construction, it’s important to find out exactly what the requirements are.” Of course, the warehouse activities had to be taken into account: The approximately 22 mister*lady employees moved about 15 million parts in about one million packages per year in single-shift operation. Around 3,600 arrivals and departures took place at the 10 loading stations.
Since the production halls employ the company’s own staff, Kempter is particularly concerned about their well-being: “A modern and energy-efficient solution was important. To achieve a good indoor climate for our people, the temperature distribution must be even and free of dust and drafts. Rudolf Kempter deliberately decided against using gas-fired dark radiators.
Technical structure of the hot air generators
The warm air generators installed under the ceiling draw in waste heat rising from the hall – such as heat generated by lighting or solar radiation – and filter it. In addition, fresh outside air can be drawn in. The air passes a stainless steel combustion chamber to bring it to the desired room temperature. Turbulent flow of the exhaust gases is generated inside the heat exchange tubes arranged on the left and right, thus ensuring optimized heat exchange. Special air outlets and return air ceiling fans distribute the air flow draught-free in the hall. The hot air distribution is controlled automatically by means of PI differential temperature control via measuring sensors in the working area and on the ceiling.
A control system regulates the temperature of the system intelligently and adapted to the wishes of mister*lady: The hall is heated individually as required. The desired room temperature is freely programmable. After an installation period of only one week, mister*lady was able to put the systems into operation.
Costs in view
Looking back, after a first winter heating season, the managing director’s expectations have been met: “The employees are satisfied. The air layering is super, as promised. The air is distributed evenly. There are no cold or warm corners, no trace of drafts.” The energy consumption is also convincing: “On normal working days, we need an average of 320 m³ of gas during the cold season, which corresponds to a cost of about €80,” says Rudolf Kempter.
Especially in the transitional period, the system does not require the burner to be switched on. Then the accumulated heat under the hall roof is already enough. The return air ceiling fans then distribute it evenly back to where it is needed. Great climate should also prevail in the summer at mister*lady. Here, the good hall insulation and the ventilation system play the supporting role. At night, the system draws in the cold outside air and has already ensured pleasantly cool temperatures in the logistics hall by the time the shift begins in the morning. This makes extra air conditioning superfluous.
Advantage: less space required for hall expansion
Another advantage of the plant will only come into play in the future. Rudolf Kempter has further plans for the expansion of the hall. He would like to add a lattice mezzanine at mid-hall height for administration. No problem thanks to the intelligent air distribution of the RBW 125. “With our heating solution, even the employees on the first floor still get warm feet. In addition, there is no need to maintain a minimum distance, as is required for radiant heaters. The space consumption would have been enormous with probably up to 70 radiant heaters needed in the logistics area,” he concludes.
Euphoniums, cajons and agogos – all these wonderful musical instruments can be found in Treppendorf in the Steigerwald in the 7,700 square meter logistics halls of the Thomann music store. In total, there are about 24,000 items here – from guitars and pianos to stringed instruments and various types of percussion instrument.
“We need a special indoor climate for storing musical instruments,” explains Stefan Thomann, co-founder and project manager for logistics at the music retailer. “The items are very sensitive; for example, if the humidity is too low, the tops of guitars can crack. With temperatures, constant air quality is especially crucial.”
Therefore, the company paid special attention to heating and air conditioning technology. Stefan Thomann: “For the pallet warehouse, we only had low temperature requirements because employees are not permanently working here. In the small parts storage area, on the other hand, we were aiming for a temperature of 16 to 17 degrees. But for incoming goods, it had to be a little warmer. The challenge with the technology: despite the three different temperature areas, it is one large, continuous hall.” This three-part temperature concept was realized by LK Metall. Two RBW direct-heated warm air generators with integrated mixed air equipment were used in the pallet and small parts warehouse, which were mounted on the hall ceiling between the two areas. An RBW warm air heater with integrated mixed air unit was also installed in the goods receiving area.
Music store Thomann
Evenly from the floor to the roof
The heating system is controlled by a building management system and several thermostats. If the temperature in one of the zones falls below a programmed set point, the respective heating system automatically turns on. Through the surface of the combustion chamber, the heat released by the burner is transferred directly to the passing air. Thus, up to 95 % of the energy used is converted directly into heat. In addition, further heat exchange of the flue gases takes place through the downstream, countercurrent heat exchange tubes, which are washed by the air flow along the entire length of the plant. At the end of the heat exchange pipes, the heated air leaves the plant via mixed air parts. Individually installed return air ceiling fans ensure uniform heat distribution over the entire height of the hall. A differential temperature control system also optimizes and reduces the temperature differences from the roof to the floor in the entire hall area to around 3 to 4 degrees.
A special feature of the system: the warm air generators can be used not only for heating, but also for ventilation. “In the summer months, the temperature in the hall is driven down by a summer night cooling system,” explains Harald Wimmer Sales Manager at LK-Metall. “This allows air temperature, air quality and air distribution to be adjusted as needed.”
Thanks to the finely tuned heating technology between the halls, the sensitive musical instruments will be safely stored in the future with regard to room temperature.
Neue Materialien Bayreuth GmbH has commissioned a new 600 t hydraulic press equipped with various temperature control technologies for lightweight components in its pilot plant. The press is used for processing fiber composites, metallic and foamed materials.
The processing of the materials involves thermoplastic composites treated at a temperature of up to 450 °C. In order to achieve maximum freedom in the working area of the press, the hydraulic unit was placed directly under the roof of the hall. This positioning favors the unhindered propagation of sound emissions throughout the hall. This would result in a high noise exposure that would be hazardous to the health of employees at the hydraulic press and surrounding workplaces. In order to protect employees from the stresses, it was particularly important for Neue Materialien Bayreuth GmbH to comply with the legal requirements and to reduce the sound pressure level at the workplaces concerned to below 80 dB(A) during operation.
The feed pumps on a 600-ton hydraulic press are a potential source of noise.
After rebuild measures: The machine enclosure from LK Metall reduces noise.
Reduce noise at the source
In order to use effective noise protection measures in such a plant, it was necessary to completely enclose the feed pumps. A site inspection revealed that the space required for an enclosure was extremely limited. It was also necessary to ensure that the electric motors of the feed pumps continued to receive the necessary fresh air for cooling. Therefore, a soundproof enclosure with a wall thickness of around 50 mm was installed to reduce noise emissions. An additional built-in fan in the cabin continues to provide fresh air to the engines.
Soundproofed ducts cover the required supply and exhaust air openings. Special supports underneath the hydraulic unit enabled space-saving installation of the enclosure. “We were able to reduce the sound level of the feed pumps from 88 dB(A) to 77 dB(A) in working mode and from 81 dB(A) to 64 dB(A) in stand-by mode,” said Carsten Schröder, technical sales at LK Metall. Compactly built Thanks to an individual sound insulation concept and a compact design of the enclosure, the customer’s requirements were met more than expected. LK Metall reduced the subjective noise pollution at the hydraulic press by more than 50%. A meaningful contribution to the protection against health-endangering noise pollution in the workplace.
Reducing wastewater pollution from degreasing baths while saving costs in terms of environmental protection is an important issue in electroplating plants.
The manufactured components must be degreased and freed from corrosion protection before a painting or coating process. With the light liquid separator from LK Metall, it is possible to use the contaminated wash liquor in the degreasing bath for a significantly longer period of time without additional chemicals by extreme removal of the accumulating oil.
LK light liquid separator: suitably designed for degreasing processes
Continuously remove oil from wash liquor
To degrease the components, they are immersed in degreasing baths and cleaned with the help of cleaning chemicals at a temperature of up to 90 °C. The oils and greases (light liquids) remain in the bath and, after a certain concentration, lead to saturation of the wash liquor. In turn, the floating oils contaminate the components and lead to a loss of quality in further processing. Suction of the oil by a simple skimmer on the surface of the wash liquor is often insufficient and too low in efficiency. Integrated into existing galvanizing processes, the easy-to-operate and low-maintenance light liquid separator from LK Metall continuously removes the oil from the wash liquor. A physically operating oil separator built into the system solves this task reliably and particularly economically. The disposal intervals are considerably extended. The oil separator guarantees high safety and long service life.
Process water treatment: degreasing with LK separator system
Longer service life reduces disposal cycles
Fully integrated into the ongoing production process, the service life of the degreasing bath is extended from about one week to around eight weeks. Compared to weekly disposal, this means an increase in service life of up to 8 times and thus a significant reduction in disposal cycles. An additional cost savings is achieved in the reduced load on the neutralization plant. Thus, on average, more than 100 liters of pure oil are separated within the first eight weeks after startup. At the same time, this means a substantial saving in chemicals. Adapted to the corresponding size of the degreasing bath, the LK light liquid separator can be integrated into almost any production process.
An interview with Harald Wimmer
Even before the 2021 federal election, sustainability and environmental protection were dominant topics in politics, society and business. The industry faces the major challenge of converting its plants to be environmentally friendly or switching to completely new systems. LK Metall from Schwabach is a specialist for environmentally friendly and climate-friendly systems and a partner in demand throughout Europe in various fields.
“We focus on sound insulation, water treatment, process technology and hall heating,” says Marketing Manager Harald Wimmer, explaining the company’s core competencies. “In this context, hall heating is our most important area,” the marketing manager continues. “Here we are innovative and individually positioned. We are able to tailor our solutions to the needs of the customer.
“We want to be CO2 neutral in a few years.”
Sales Manager, LK Metall
Just recently, LK Metall equipped a company with the world’s largest milling center, where, among other things, gear wheels for wind turbines are machined, with two RBW warm air generators with condensing boiler technology. “The challenge here was that the temperature difference from roof to floor could not be higher than a maximum of two degrees,” says Harald Wimmer. “We developed a special distributor head for this purpose, a Thermovent mixed air distributor, which uses fans to take the temperature cushion and incorporate it into the heating flow. Via this solution, we were able to reduce the temperature difference to 1.5 degrees.”
In the field of sound insulation, LK Metallwaren focuses mainly on wire drawing machines. The interweaving of metal wires creates a significant volume. LK Metallwaren is able to reduce the noise level to 70 to 80 dBA, allowing employees to converse at the machines at a normal volume.
With its solutions for water treatment, the company is particularly in demand among automotive suppliers. “The process wastewater generated must be cleaned,” says Harald Wimmer. “Politicians are imposing ever stricter rules here, for example in what degree of purity the water may be discharged. This is where we can help. In addition, we also offer a complete service around the clock for the plants.”
In process technology, LK Metallwaren focuses primarily on solutions for painting and drying, and supplies well-known manufacturers of powder coating and painting systems with supply and exhaust air systems. Air filters with three stages complete the portfolio of LK Metallwaren. The filters are available in dust, activated carbon and H14 stages, which filter out 99.995% of viruses and bacteria from the air.
Leading in process technology
“We are at the forefront of the market in process technology, and we are also in the top third of the market in the segments of water treatment, hall heating and sound insulation,” says Harald Wimmer, explaining the company’s market position. “We have customers from a wide range of industrial segments, for example from the automotive sector or machining, but we have also equipped event and trade fair halls. In the process, we work for companies of all different sizes, for small automotive workshops as well as for corporations.”
LK Metall is positioned throughout Europe, particularly strong in the DACH region. In the coming years, the company intends to consistently expand its international market presence. “Customers get exactly the systems they need from us, not off-the-shelf solutions,” says Harald Wimmer, explaining the company’s success. “This is our big advantage over competitors, who in most cases can only offer standard solutions.” LK Metall trains skilled workers itself and has sound know-how.
Security and social benefits
The company invests heavily in the training and further education of its employees and relies on state-of-the-art technologies. For example, since 2019 they have been operating a fully automated swing bending center. “It is important to us that our employees can work under optimal conditions and feel comfortable with us,” says Harald Wimmer. “That’s why we place a high value on safety and offer good benefits.”
In the coming months, LK Metall will combine the RBW warm air generators and the REKU ventilation system with heat pumps. In addition, the further development of the combustion chambers as well as the hall heating systems with EC motors are an important topic in order to be compliant with the ERP and the climate protection laws.
LK Metall’s vision is clear: “We want to be CO2-neutral in a few years and run our plants on hydrogen,” says Harald Wimmer. “We hope that politicians will move more strongly and that the industry will be even more responsive to process heat. Overall, we are confident about the future.”
The interview was conducted by the Economic Forum.
The RBW decentralized warm air generators from LK Metall are an efficient and climate-friendly heating solution for large production halls.
In order to heat the new light-flooded production hall with a total area of around 32,000 m2 evenly and effectively during the annual heating period and to achieve a pleasant hall climate in summer, the axle manufacturer commissioned Kessler+Co. GmbH & Co KG from Abtsgmünd, Germany, provided the LK Metall company with a climate-friendly heating system using effective condensing boiler technology.
A total of 12 decentralized warm air generators of the RBW type were installed over a wide area under the hall ceiling. In order to achieve a uniform temperature of around 18 °C during the heating period, rising hall air is extracted, filtered and heated via the combustion chamber and the designed heat exchangers and fed back into the hall without drafts. The decentralized warm air generators are each heated with a natural gas-fired gas blower burner.
Warm air heater RBW for Kessler+Co
Additional use of waste heat
The rising warm hall air from process heat and the solar radiation via the skylights are an additional usable heat source for the warm air generator. The hall air extracted and filtered under the hall ceiling mixes with supplied fresh air. Due to the additional use of waste heat in combination with the modulating burner operation of the units, the RBW warm air generators consume significantly less energy.
“The use of the decentralized warm air generators type RBW for heating production halls is a convincing contribution to climate protection,” says Harald Wimmer Sales and Marketing Manager for hall heaters at LK Metall, “Because the additional use of waste heat means that less fossil fuel is consumed. This significantly reduces CO2 emissions.” The heat output range of RBW warm air heaters is from 40 kW to 160 kW. Special knitted metal filters made of stainless steel clean the hall air from dust particles and aerosols from production. Around 90 installed return air ceiling fans reduce the temperature stratification over the entire hall height to 0.3 °C to 0.5 °C per rising meter. These are regulated by sensors in the ceiling and floor areas.
Cooled hall air in summer
In the summer months, the RBW warm air generators improve the hall climate through the mixed air device. An automatic night-summer ventilation control system uses the cool outside air at night to cool the hall air, reducing accumulated heat from the day back to a comfortable temperature. “Thus, the RBW warm air heaters are also used in summer to maintain a pleasant daytime temperature,” said Harald Wimmer after commissioning the heating systems at Kessler+Co.
Central control from PC
A modern PLC flexibly controls the warm air generators. All settings are made via the respective touch displays on a total of four control cabinets. In order to be able to operate the twelve warm air generators centrally via a PC, the systems were integrated into the company’s network. Regardless of the size of the production and manufacturing halls, the RBW warm air heaters from LK Metall are a flexible, efficient and infinitely scalable heating solution with an extremely high efficiency of up to 99% based on the calorific value, thanks to the decentralized installation under the hall roof.
LK Metall supplies a 2-stage water treatment plant, overcomes the challenges and lays the foundation for future cooperation. The customer is a leading global supplier of constant velocity drive shafts for the automotive industry with a total of several thousand employees in 30 countries.
In 2016, LK is commissioned to design and implement a solution for the treatment of washing water and emulsions containing oil and graphite from the forge at the site in Rhineland-Palatinate.
The source of environmentally friendly water treatment
While the precursor separation plant separates the light and heavy phases from the wastewater, the ultrafiltration plant prepares the pretreated wastewater so that it can be fed into the public sewer system. The small amount of separated residual material is fed to the disposal route via a double-walled storage tank. Both plant sections are automated and communicate via an Ethernet interface. By linking the two plant sections, it was possible to operate both plants from spatially independent control panels and to monitor the operating states. The entire plant is equipped with a remote monitoring module that provides secure access to the plant’s control system. A fault and warning notification system informs the operator in real time by e-mail about the current plant status.
“Barrages” on the way
This is where the first challenge of the project arises. Although a total volume of 1,600 m³ per year of wastewater is generated, fluctuations and peaks in wastewater volumes must also be taken into account for the functionality of the systems. In particular, the adhesive properties of the graphite component have been crucial in the system design and selection of the MSR technology. Project engineer Jan Graeber of LK Metall explains the problem: “We already have to set up the planning so broadly that we can cover all eventualities.” In order to be able to channel the supply of the different wastewater streams and to realize a nearby location of the plant, it was decided to build a separate hall, especially for LK’s ultrafiltration plant.
The project comes into flow
After a previous on-site plant test and membrane test runs in LK’s laboratory, the project will be implemented within a few months in 2019. Here, LK Metall faces the second challenge: The installation site is located close to the Moselle River in a flood protection area. Therefore, the plants must be erected about 70 cm above the ground so that containers do not float and the technology is not damaged. Nevertheless, after the preparatory work, the team of fitters, electricians and programmers manages to complete the installation in two construction phases in a total of just seven weeks.
In order to ensure a coordinated start-up of operations and the required work output of the plants, the business partners agree on an accompanying phase starting in January 2020: For this purpose, the project engineer is personally on site, checks the smooth operation, determines that the desired values are correct and expresses his satisfaction: “The most beautiful thing about such a project is to see that the plants work as planned.” In order to ensure long-term operation, a service technician from LK Metall will be at the client’s site on a regular basis until the end of 2020 in order to be able to respond to unusual incidents.
The mouth in satisfaction
For the client, the success of the project has paid off: the new plant saves the company high disposal costs because the wastewater is suitable for indirect discharge. And it conserves water as a resource because the treated wastewater is easier to recycle. Not least for this reason, further projects are already being planned.
Steadfastness and tenacity, but above all the ability to overcome the odd dry spell when it comes to achieving one’s own goals on time: This is what distinguishes the company LK Metallwaren and its employees.
The goal that our Purchasing Manager Gerhard Gleixner had set for November 5 on the occasion of the Nuremberg Megamarsch 2022 immediately seemed endlessly far away: Fifty kilometers were to be covered on a circular route through the Franconian metropolis in a period of less than twelve hours – on foot, mind you.
Gerhard Gleixner – at 58 years of age fitter than his sneakers – left no doubt at any time that he would complete the course on time to be back home in time for shopping.
In the end, he even made it under the magic ten-hour barrier during his forced march. The reward: certificate and medal he finally accepted in the certainty that his circulation can withstand even strenuous circle runs like this without any problems.
PS: LK Metallwaren managing director Jochen Haberkorn was absent this year, but announced on the occasion of Gerhard Gleixner’s silver company anniversary next year that he would follow closely on his heels on the 50 km course.