VOL. 25 May ISSUE YEAR 2024


in Vol. 25 - May Issue - Year 2024
Striving for Enhanced Sustainability and Economical Efficiency of Mass Finishing Operations
Ruediger Böhm, Head of Global Research and Development at Rösler Oberflächentechnik GmbH

Ruediger Böhm, Head of Global Research and Development at Rösler Oberflächentechnik GmbH

Increasing the size of a grinding media by 1 mm can result in a 12% longer usable life representing a significant cost saving

Increasing the size of a grinding media by 1 mm can result in a 12% longer usable life representing a significant cost saving

The multi-shape media was developed with an AI-based software

The multi-shape media was developed with an AI-based software

The non-foaming plastic media makes mass finishing processes more stable and reduces cycle times. A win-win situation for the customers!

The non-foaming plastic media makes mass finishing processes more stable and reduces cycle times. A win-win situation for the customers!

The anti-dust additive for drying operations with organic drying media prevents dust from contaminating the work piece surface and ensures a cleaner working environment

The anti-dust additive for drying operations with organic drying media prevents dust from contaminating the work piece surface and ensures a cleaner working environment

Fully automated Rösler mass finishing system. The entire system requires one person – for supervision!

Fully automated Rösler mass finishing system. The entire system requires one person – for supervision!

Digitization will play a key role in making our processes more efficient and cost-effective

Digitization will play a key role in making our processes more efficient and cost-effective

Today’s business environment is characterized by a high degree of uncertainty. Issues like the looming climate crisis, global supply chain problems and growing cost pressures are posing serious challenges for any business. It becomes increasingly more difficult for suppliers to satisfy the customer needs. Today, eco-friendly solutions are not only demanded, cost-efficient and competitive solutions are also expected. Above all, the businesses make sustained efforts to be sustainable and provide long-term cost stability, not just for a few months but for several years. Of course, these challenges apply to everybody, including companies active in the field of surface treatment. MFN had the opportunity to talk with Ruediger Böhm, head of global research and development at Rösler Oberflächentechnik GmbH. Specifically, we wanted to learn how Rösler, the global leader in surface refinement technologies such as mass finishing, shot blasting and post processing of AM products, is adapting to this new, more difficult business environment.

(?) MFN: Rüdiger, nowadays phrases like ”sustainability”, “saving of valuable resources” and “environmental protection” have become part of the business vocabulary all over the world. They can be spotted in nearly every PR publication and numerous advertisements. How is your company dealing with this new and challenging situation? 

(!) R. B.: You might want to add another important term, namely “supply chain stability”. Before going into specifics, let me explain what we at Rösler understand under sustainability. For us, sustainability means “providing surface finishing solutions that save valuable resources, are eco-friendly and, above all, represent a tangible, long-term economic value to our customers”.

How do we cope with these, no doubt, more difficult business conditions? We must direct our entire focus to the customer requirements. A “one size fits all” product package is no longer acceptable. Practically, all the processes we develop must be tailored to the specific needs of our customers. Let me express this in another way: 90% of all our finishing solutions are custom-engineered nowadays - with special emphasis on quality but also long-term economic viability for our customers.

(?) MFN: Are you mainly concentrating on equipment?

(!) R. B.: Absolutely not. The cost and quality challenges apply equally to equipment and consumables. This is not surprising, because the consumables represent a huge cost factor. The media and compound purchases of our top-line customers amount to hundreds of thousands of Euros every year. In a few cases even millions!

(?) MFN: To us, the goals of high finishing quality and long-term economic viability/cost efficiency seem to be a bit contradictory. How do you deal with this contradiction?

(!) R. B.: Be assured that we never compromise on quality. We achieve our leading market position with first-class finishing solutions, and we want to keep it this way.

However, we check every finishing process, whether new or already existing, for its environmental sustainability and, above all, its long-term cost-effectiveness. This means that a large portion of our R & D efforts is focused on making existing products more efficient, but the development of new products is not left behind. This applies to the equipment as well as the consumables side.

(?) MFN: Can you give us some examples?

(!) R. B.: Let us look at an established process that has been used for several years. The results are excellent, and the costs were manageable. Now, because of drastic cost increase for our raw materials, we have had to raise our media and compound prices, making the process significantly more expensive. In such cases, we turn the entire process upside down to look for savings.

(?) MFN: Can you be more specific?

(!) R. B.: First we might look at the media, which is the largest cost factor in general cases. For example, we might be able to take advantage of a somewhat larger grinding media. This can make a huge difference.

(?) MFN: Please explain.

(!) R. B.: Let us say, the customer has been using a 29 mm plastic cone. By increasing the size by 1 to 30 mm, a 12% longer usable life is expected for this particular product without jeopardizing the finishing quality.

(?) MFN: Isn’t this an over-simplification?

(!) R. B.: Not at all. You might be amazed at the amount of money we can save for the customers by optimizing their processes. Let me give you another illustration. Sometimes our customers use media that is not perfectly matched to the respective finishing machine. For example, they use a very abrasive but fast-wearing media in a high-energy centrifugal disk machine. A slower wearing media might produce the same good results but will last 30% longer. This can result in savings of thousands, even tens of thousands of Euros.

(?) MFN: What about new products?

(!) R.B.: We develop new products consistently. For example, our multi-shape ceramic media on the media side was a real breakthrough.

(?) MFN: This sounds complicated.

(!) R. B.: Not at all. Through the intensive “rubbing” interaction between media and work pieces, the media wears and is increasingly smaller. At a certain size, individual media stones tend to lodge in the work pieces, producing possible catastrophic effects on downstream manufacturing and assembly operations. By virtue of an AI-based simulation program, we developed a new media in an entirely new shape. It maintains its original shape, even as it becomes smaller, and does not get lodged in the work pieces.

The innovative multi-shape media not only lasts longer but also reduces the cycle time. A double win for our customers!

(!) R. B.: Another success story is our non-foaming plastic media. The use of plastic media in finishing operations tends to cause extensive foaming. Because of its buffering effect between media and work pieces, foam can reduce the grinding performance, resulting in unwanted cycle time increases. Foam will also contaminate the work pieces with metal and media fines. In the past, the foaming issue had to be controlled by injecting special defoaming compounds into the finishing machine making the process less stable and more expensive. 

(?) MFN: So, how did you solve this problem?

(!) R. B.: We developed a plastic grinding media that no longer produced unwanted foam. The results are impressive: The specified finishing results are achieved in shorter cycle time, the entire process becomes more stable, and less compound is used. Again, a win for improved sustainability and long-term economic benefits for our customers.

(?) MFN: Do you have any other success stories?

(!) R. B.: We are constantly working on new consumables. Sometimes, we create new media and compounds when developing or optimizing certain finishing process for a customer.

Another development for long-term ecological sustainability and long-term economic benefits for our customers are our long-life compounds for process water cleaning and recycling operations with centrifuges. While centrifugal cleaning and recycling generates huge savings in water and compound consumption, the process water is eventually seriously contaminated and must be replaced with fresh water and compound. Disposing of the contaminated liquid is not only expensive but also disrupts the finishing operation. With our recently developed long-life compounds, the time period between process water exchanges could be doubled. Huge cost savings! The long-life compounds are also resistant against unwanted bacterial infection. This eliminated the need for injecting expensive biocides into the process. 

Let me just say a few words about our anti-dust additive for drying operations with organic drying media such as crushed corn cob, generally known as maizorb. Organic drying media produces an excellent drying effect, but dust will come along and settles on the work piece surface. This can cause problems with subsequent manufacturing operations. In addition, the generated dust also pollutes the immediate environment around the finishing operation. With our new anti-dust additive, we could completely eliminate the dust problem.

(?) MFN: What about your equipment?

(!) R. B.: Here we work on two fronts: First, we work on increasing the efficiency and automation of the finishing operations. Second, we want to reduce the operational costs. Here our main focus is on reducing energy consumption. Targeting at both areas, we have been developing sophisticated digital tools.

(?) MFN: Tell a bit more about these efforts.

(!) R. B.: Let me give you one simple example, which might sound a bit trivial but proves to be very effective. Practically all our machines are equipped with frequency inverters nowadays, allowing the adjustment of the drive systems, be it vibratory drives, the motors of our blast turbines, the drive motors for roller conveyors, conveyor belts, etc., to the exact required speed. This not only improves the efficiency of our mass finishing and shot blasting processes but also saves energy.

We are also constantly improving the energy efficiency of our driers. These are essential accessories for pretty much all mass finishing processes. But they are a huge cost factor amounting to thousands every year. Let me explain: The heating system of a drier can use up to 60 kWh. At 0.25 Euros per kWh, this amounts to hourly costs of 15.00 Euros. In a 24/7 mass finishing operation where the equipment is running more than 5,000 hours per year, this can amount to a whopping 75,000 Euros every year.

With an innovative heat pump/condensation system in our hot air belt driers, we are able to cut the energy requirements for the drying operation by up to 75%. This alone represents annual cost savings of tens of thousands.

(?) MFN: How does this work?

(!) R. B.: We are guiding the moist air, picked up from the work pieces by the drier, through a dehumidification module, where the moisture precipitates on the fins of an air cooler. In a subsequent air heater the dehumidified air is then re-heated to the specified drying temperature. Of course, this is a bit more complicated than it sounds and, by the way, we have filed for a patent for this revolutionary drying system. 

(?) MFN: How about other drying systems?

(!) R. B.: With a simple design change in our vibratory dryers, we could reduce the average energy requirements for the drying operation by 50%. Again, this translates into annual cost savings of thousands of Euros. 

(?) MFN: Any other success stories?

(!) R. B.: Rösler is actively pursuing its goals for long-term sustainability and cost-efficiency with the automation and digitization of mass finishing and shot blasting processes.

(?) MFN: Why is automation so vital for sustainability and cost-efficiency?

(!) R. B.: Rösler has always been a leader in the field of automation. But since in today’s business environment it is extremely difficult to find qualified, well-trained mechanical personnel, automation is frequently the only means for economic survival. Our customers are telling us all the time that it has become practically impossible to seek out the right people for physically demanding operations such as manual belting, grinding or buffing. Automation is the only feasible way out of this dilemma.

(!) R. B.: But automation helps not only with today’s personnel shortages. Taking the human factor out of mass finishing and shot blasting operations significantly improves the finishing quality. In addition, automation guarantees a stable process environment and ensures absolutely repeatable results. A significant step towards the “zero defect” goal!

(?) MFN: Why is Rösler so strong in the field of automation?

(!) R. B.: For many years, our company has not only built the actual mass finishing and shot blasting machinery but also a wide range of material handling equipment like conveyor belts, roller conveyors, vibratory hoppers, all kinds of loading devices, etc. In addition, a powerful electronics team is always available that utilizes the most modern control devices. So, very early on we became a specialist company in automation. Today we are not only using the latest PLC controllers but also multi-axis robots, devices to encode the work pieces with a data matrix, bar code scanners, and special recognition systems. These are used to detect finishing media that might be lodged in the work pieces or work pieces that do not belong to the process. In such cases the system triggers an alarm and physically discharges the faulty pieces from the operation.

(?) MFN: You had mentioned digitization?

(!) R. B.: Yes. We even have a department, called “Rösler Smart Solutions” that specializes in digitization solutions.

(?) MFN: What do you mean by digitization?

(!) R. B.: Digitization goes beyond the mere automatic work piece handling. The goal of our digitization modules is to lower operational expenses, make our finishing processes more stable and help reduce personnel costs. This is achieved through innovative software in combination with high-tech sensors. With these tools, we continuously monitor and analyze key machine components and process parameters. The software not only displays any deviations from the specified process parameters but also proposes corrective action.

(?) MFN: Please give us some examples.

(!) R. B.: One good example is the digital process water management system for cleaning centrifuges. Cleaning and recycling the process water from mass finishing operations is excellent to reduce the water and compound consumption by more than 90%. But, maintaining such a system is highly complicated and, therefore, difficult. It requires the control of numerous parameters like pH value, compound concentration, water hardness and many more. To date these parameters have to be controlled manually by well-trained, experienced people. Our process water management system digitally measures up to 13 process parameters with suitable sensors. Whenever a value is out of its specified range, the system proposes detailed corrective actions. This not only eliminates human error but makes the recycling operation more stable and prevents unforeseen equipment downtimes. So far, the customers using our system are enthusiastic about it.

In shot blasting operations, our digitization software monitors, for example, the blast media flow rate, the quality of the media mix, the amperage draws of the turbines and many more. Our digitization software also helps to optimize preventive maintenance. By keeping track of the operating hours and analysing actual uptime statistics for all critical wear components, the digital systems will automatically release spare parts orders. 

Digitization has only just started. But the digital modules we have implemented so far prove to be extremely beneficial to our customers. They have improved equipment uptimes, practically eliminated any rework and helped our customers save a lot of money. We anticipate digitization to play a huge role in our efforts towards more sustainability and long-term cost-efficiency.

(?) MFN: Rüdiger, thank you for your time. 

MFN would like to thank Ruediger Böhm for this interview!

Rösler Oberflächentechnik GmbH

Vorstadt 1, 96190 Untermerzbach


Tel. +49.9533.924-802

E-mail: d.hund@rosler.com