We are very excited to be speaking today with Mr. Andreas Fritz, CEO of cleaning system experts “HEMO”. In our opinion “HEMO” offers the most advanced cleaning technology solutions in the heat treatment industry. Read on.

“The Monty Heat Treat News” is very excited to be speaking with Mr. Andreas Fritz, Managing Director of “HEMO”, a German firm known as one of the foremost in the world when it comes to cleaning systems. Andreas lets start off today with some background, why don’t you tell us about your personal background and also that of “HEMO”?

“Dear Gord, thanks for having me in this most excellent heat treatment source. I appreciate all the information you provide to us and of course being a part of it.

In 1999 I joined the company as a temporary help after school. I did whatever was necessary in any department, was fascinated by the size and technology of the machines and finally agreed to do an apprenticeship. After that I did a 6-year distance study in order not to lose the daily business and also spent 3 years at a near Nuremberg manufacturing wire drawing machines. That helped a lot to gain knowledge and different perspectives concerning organization, development of foreign markets and provision of a global service structure.

Since 2012 I have been CEO and pretty much involved in the heat treatment industry.

To be honest, customers in this industry are different than in others. The direct, honest way of talking – negative and positive – is and was very helpful especially in my first years. It is like a big family and I really like to meet these people whenever and wherever possible.” 

From background let’s move on to what “HEMO” has to offer, your range of products, your capabilities and specifically what you have done in the heat treatment industry.

“We are supplying high end cleaning machines which are customized. Our machines fit into any application, any place in your heat treatment line and communicate with any operating computer system. 

This starts with one tank solvent machines for cleaning after oil quenching. Half of our orders in this section are substitutes for existing spray /dunk washers because they don’t provide staple quality, costs for water disposal are increasing and the refurbishment of a hot zone of tempering furnace is also very expensive.

Our hybrid cleaning machines are very popular in cleaning before gas nitriding and LPC because the hardened parts later on are spot free and of the highest quality. 

And of course, our machines run 24/7 like furnaces do. Hence the quality is of the cleanliness and the machine itself are of highest importance.”

Years ago, an individual who I had a very high opinion of, Mr. Phil Dennis of H & S Heat Treating told me that the key to good heat treating was clean parts. While Phil unfortunately passed away a number of years ago, I have always remembered his words of wisdom and have come to agree with him (although I confess at the time I wasn’t convinced). I am sure you would agree with his statement but why is it so important to have clean parts? 

“Our business in the heat treatment industry started in 1996 when we sold a machine to a supplier of BOSCH. This captive heat treater delivered the parts to BOSCH and they returned them because they were not hardened. Since it was normal at that time that hardened parts were black and dirty, BOSCH Quality Manager did not even test the degree of hardness. Finally, we explained that cleaned parts before heat treatment are clean parts after that as well and after testing the parts they were accepted. From that day on cleanliness became very important in the heat treatment industry. Earlier dirty parts were supposed to be heat treated, nowadays they are scrap and will not be accepted. I’m sure this will more and more also become normal in the North American market.  

Especially the scrap rate is very important in many industries. Cleaned parts have a much lower scrap rate than dirty ones. We supplied machines to the UK where parts are heat treated for Formula 1 racing cars. Due to budget caps every dollar is important for the development of upgrades that can make the cars faster. Hence many parts are manufactured individually and not as a series. When you are manufacturing one of these critical, complex parts and the heat treatment is not good, you have to dump it. This causes costs and waiting times. Hence the heat treatment shops trust our cleaning machines and reduce the scrap rate down to zero.

Last but not least clean parts protect your equipment. Dirty parts bring a lot of different chemicals into the furnaces which causes trouble in the environment due to emissions and has influence on the hardening processes because of adhesions on the furnaces’ walls. Organic residues like oil vaporize in the furnace and crack the walls. This also causes very high costs of refurbishment.”

The first time I visited your facility in Otisheim, Germany I was absolutely astounded at the quality and complexity of some of your cleaning systems. Perhaps complexity is the wrong word, let me change that to heavily engineered. This obviously means that these are not inexpensive systems, my question would be how can you compete with a cheap and dirty dunk/spray washer? Or do you try and compete with these more basic solutions?

“We do not try to compete with these washers because we are unable to do. In 1996 HEMO delivered the first vacuum cleaning machine using hydrocarbon far above its flash point for perfect cleaning and drying results to a commercial heat treatment shop.

Very important is that the whole system is running under full vacuum throughout the whole cleaning cycle – not only for the drying process.

The cleaning process is supported by high temperatures above the solvent’s flash point, pressure flooding, rotation or oscillation of the parts, ultrasonic or Organic cNp which is a kind of cyclical nucleation process – very good for blind holes e.g.

This technology causes costs in manufacturing but also provides huge benefits. Our customers really deal with facts like the costs of current spray/dunk washers including the total costs from water disposal and fresh water over the maintenance workers costs to costs of scrap parts caused by bad cleaning. Very often they find out that the total costs of our system within e.g. 10 years are even less than those of the cheap washer even though investment costs are a multiple of the spray/dunk washer. 

In Germany we say, if you pay for a Volkswagen, you receive a Volkswagen and not a Mercedes.”

Some time ago I sold for a period of time vapor degreasers. In my humble opinion these were a very effective cleaning system, perhaps amongst the best ever devised but health and environmental concerns have led to their partial demise. Can you tell us what the EPA currently has to say about vapor degreasers? What is your alternative?

“A proposed EPA rule regulating perchloroethylene (PCE) will impact the parts cleaning. The rule proposes that PCE can be used in vapor degreasing, but only if a challenging ECEL of 0.14 ppm and requirements to prevent skin exposure are met. The ECEL (Existing Chemical Exposure Limit) is the workplace exposure limit determined by the EPA.

Similar regulations for more hazardous solvents such as Mehylenchloride or NPB are already law. This means that any open top vapour degreaser in the US will have to be substituted. Even closed system cannot reach the ECEL limits hence there will not be any other chance than moving to harmless solvents such as modified alcohols. These solvents are flammable but harmless under vacuum and will be the future of parts cleaning in North America like they are nowadays already in Europe.

Due to these changes in environmental and health legislation, HEMO invented and patented the first cleaning machine which was working under vacuum in 1995. Since then we have manufactured more than 2000 systems in any size and for a large variety of branches and customers. These full-vacuum systems will be the only solution to meet the governmental legislation.” 

Water or solvent based systems? Both are available I know, does “HEMO” offer both and if so, what are the relative advantages/disadvantages of each?

“In our explanations we always start with the basic rule “like dissolves like”. This means that organic contamination can be removed best with an organic detergent which is in our case a solvent like hydrocarbon or modified alcohol. Quenching oil is the best example in that case. Cleaning it off with water is very inefficient. On the other hand, inorganic residues like water-based coolants cannot be removed with solvent without leaving salt residues as white spots on the parts. In that case there is nothing better than water and detergent. 

Still roughly 70% of the systems sold are water-based but this number has been decreasing for decades now. We mainly focus on the solvent systems because we want to sell stable cleanliness. This is not possible by using water-based systems where the concentration of the detergent changes all the time and the quality gets worse until you change the whole bath. In our machines you never have to change the solvent and it provides continuous quality.

Sometimes we combine solvent and water in case it makes sense to reach perfect cleanliness or, like in commercial heat treatment shops, a variety of unknown contaminations are on the parts when they arrive for heat treatment. In this case we use our HYBRID and BEYOND machines.

In 2001 we invented our hybrid cleaning machines. This gives companies more flexibility and maximum clean parts because you can clean them in the same machine using a solvent and/or a water-based media.

In 2018 we invented a new technology called BEYOND. In this case you also have a water-based and a solvent-based cleaning cycle but in difference to the hybrid system, the two medias are not separated but mixed. This help getting a shorter cycle time with similar cleaning results compared to the hybrid system.”

Are your cleaning solutions dependant upon the heat trying process? For instance, would you offer the same solution to somebody doing gas nitriding as opposed to carburizing? What about LPC?

“The machines itself can be used in any heat treatment process and line but the demands for cleanliness are different. In case hardening cleanliness does not really matter. Very often the parts will have additional manufacturing steps like grinding after the hardening. Then optical issues do not play a role. 

In LPC or in nitriding a clean surface is very important to have a perfect bonding layer and the heat treatment is the final step of manufacturing hence all spots or stains on the part will cause discussions with the Quality Management of the customer.” 

Do you have the ability to fit into most heat treatment lines? Obvious examples would be a standard batch IQ (Sealed Quench) line? A pusher furnace? A modular LPC system?

“We can build any batch size and put our machine into any heat treatment line. That’s a big benefit for our customers because there is no need for additional handling of the parts and the line can run in full automatic mode.

Pusher furnaces are also possible. In that case the lowest cycle time is important for us. We just delivered four machines into a new case hardening pusher line in Germany. Each line had two cleaning machines, one for pre-cleaning before hardening and one for cleaning after oil quenching before tempering. The customer had more than 400 different parts. We took the shortest cycle time which was 8 minutes and checked what we need. For pre-cleaning with our Beyond system we needed approx. 20 minutes and for post-cleaning with hydrocarbon only approx. 15 minutes. Hence, we designed the pre-cleaning machine chamber to collect 3 batches and clean them at the same time because 3x 8 minutes is 24 minutes and we needed 20 minutes. The post-cleaning machines was smaller taking only two batched the same time and cleaning them in 15 minutes. The batches are collected in the cleaning chamber. After the cleaning process they are separated from each other again. We cannot be faster than physics allow us to be hence we need to be creative in the design department and finally find good solutions for our customers.

Modular LPC systems are very popular and we are also part of this market. Together with ECM we found a very good way to implement our cleaning systems into their LPC lines.” 

The previous question leads to another one-where are most of your systems installed? Vacuum hardening applications? Continuous either mesh belt, cast link or pusher? LPC?

“Most of our systems are installed in Batch IQ (Sealed Quench) lines. Main reason is that we substituted the existing spray/dunk washers there. Since we are well-known in that section for decades, most inquiries still are Batch IQ size machines.

Vacuum or atmospheric keep the balance since LPC is pretty much increasing. For our technology it doesn’t make any difference.

For pusher lines and roller hearth furnaces we found a way to handle the short cycle times by collecting batches in the machine and separating them after the cleaning again. Hence this is a new but growing field for us.

Impossible still are mesh belt furnaces since we clean under vacuum and therefore you need to have a batch that is cleaned in a closed chamber.” 

Are you able to share with us the names of some customers in the heat treat industry that you have worked with over the years?

“We have signed many NDAs hence it is not easy. But of course, we supply major commercial heat treaters like Bodycote, Aalberts and Braddock. 

Many of the biggest global captive heat treaters also use our systems. Same counts for the big automotive suppliers and gear manufacturers.

But also, smaller heat treaters are using our systems even though the investment is quite high for them. Very often they supply a niche industrial segment or have a special way of heat treatment and combined with highest cleaning quality they can work more profitable as they could do without a good cleaning system.

Very important for us is that the main furnace manufacturers such as e.g. Ipsen, Aichelin, ECM, Rübig, regularly consult us in case of projects with high cleanliness demands. Together we then realize these projects, and both have a benefit out of such kind of collaboration.

I think that says a lot about the reputation we have in the heat treatment industry and we are very proud about that.”

Do you see attitudes in the heat treat industry changing when it comes to cleaning? I mentioned earlier that basic dunk/spray washers are probably the norm around the world. They are basic, simple to use and relatively inexpensive and probably in many cases completely adequate but nobody would argue that they are the best solution possible. Are you seeing more interest in improved cleaning solutions?

“Yes, attitude is definitely changing. Cleaning is not anymore something nobody pays for, something people will start laughing when you put it into your price calculation. Cleanliness is important and it separates good and bad quality of parts. When parts are badly cleaned, very often they are also badly heat treated. Quality assurance starts with the eyes and when a heat-treated parts is clean the first test is already passed. 

In Europe it is already normal that commercial heat treaters are not only selected by heat treatment capacity anymore. It is also important if and how good they can clean the parts because. This finally became a second core competence beside the heat treatment.”

Last but not least what does the future hold for “HEMO”? Can you see more manufacturing facilities? An expanded product line? Perhaps acquiring competitors? I can promise that anything you say will be held in the strictest confidence, just between ourselves and our thousands of readers around the world. 

“We are always positive and see a very bright future for our company. The size is perfect, the way we work is very efficient and the technology we offer is innovative. With our Surface Alliance, a group of specialists we are shareholder of, we are able to supply any kind of cleaning system to anywhere in the world. Last step was the creation of Washtech in Queretaro, Mexico, and the Surface Alliance Cleaning Corporation as our US sales unit. 

At the moment we are working on a Joint Venture in the US to increase our sales and service capabilities. I think the US market has a huge demand for cleaning systems and we have what the market needs. But without local sales and service it will be hard hence the establishment of a local company is our first priority at the moment.

We also increase our customer base in other kinds of heat treatment such as brazing and annealing. There is a lot of potential and we are looking forward to new challenges.

Thanks very much for having me here.”

Andreas I really appreciate your time and look forward to visiting your facility the next time I am in Germany.

Did you like this article? Click here to subscribe to The Monty.

View our recent magazines and podcasts by clicking the following link. https://themonty.com/magazine/