Mr. Andreas Fritz, Managing Director, HEMO GmbH

We are very pleased to be speaking with Mr. Andreas, Fritz of cleaning system specalists HEMO GmbH in Ötisheim, Germany.

Right off the bat Andreas I have a question for you about the name of your company. I had always thought it was EMO however I see that the company name is now HEMO GmbH-which is correct?

“HEMO is the correct name of the company. The two companies Hoesel GmbH, manufacturer of fine cleaning machines, and EMO Oberflaechentechnik GmbH manufacturer of large cleaning systems merged in 2017 and changed the name to HEMO. Nevertheless EMO is still our brand name in the heat treatment industry and the machines we sell there are still called VAIOCS (Vacuum Assisted Inorganic Organic Cleaning System).”

I am always curious about how people get involved in our industry-could you share with us your background and that of the company?

“The company was established in 1979 building open-top atmospheric degreasing system using chlorinated hydrocarbons as solvent which was state of the art at that time. Due to changes in environmental and health legislation we invented and patented the first cleaning machine which was working under vacuum in 1995. This new technology had a huge impact and finally all competitors were our licensees.

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. Their customer was BOSCH and their quality control returned the whole batch stating it was not in the furnace because the parts were not black after tempering. Only reason was that the parts were cleaned after oil quenching and the oil didn’t crack on the parts anymore after tempering process. Finally, for a certain time, BOSCH stated in its specification sheet that all parts must be EMO-cleaned which was our boost into the heat treatment industry.

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 loose the daily business and also spend 3 years at a machine manufacturing company near Nuremberg.

Since 2012 I am Managing Director and pretty much involved into 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 for me to guide me especially in my first years. It is like a big family and I really like to meet these people whenever and whereever possible.”

Please share with us a little information about your company; Size? Products? Locations? Industries you are involved with?

“HEMO GmbH currently has roughly 140 emloyees and a turnover of 35 Mio. Euro being generated at two manufacturing locations in the south of Germany. We are shareholder of the the companies LPW Reinigungssysteme building water-based cleaning systems and BERTOMA which is a job-cleaning company.  Additional foreign joint-ventures are Mecanolav-Ridel in France, NGCT Cleansys in India and the latest one Washtech in Queretaro, Mexico which all offer sales, service and manufacturing capacity for HEMO products but also build their own kind of cleaning systems.

Finally we have a licence manufacturing and service partner in China being done by Shanghai Advanced Metallurgical Technology Corporation. In any of these locations our custom-tailored solvent-based or hybrid cleaning machines are build or used. Roughly 25% of our turnover is generated in heat treatment industry (hardening and brazing) followed by coating, automotive and aerospace industry.”

Is your equipment typically a standard design or more custom machines?

“Our equipment is always custom-tailored. For sure we adapt furnace batch sizes from well-known manufacturers into our „standard“ but even small differences in batch dimensions cause differences in filling volumes, tank sizes, piping diameters and many more details. We are used to that and the customer is mainly interested in the layout of the whole furnace line. And by the fact that roughly half of the supplied machines substitute old existing spray washers we must be able to implement a much more sophisticated machine into the existing floor space. This is our strength and makes us competitive enough to be a well-known partner in this industry.”

In the heat treating industry how important is part cleanliness-let me rephrase that slightly. Nobody will argue that in an aerospace application as an example parts have to be clean, however if you are heat treating fasteners in a furnace with oil quenching is cleanliness really that important?

“Basically there is more than one reason why cleanliness is important. A good cleaning system cleans the parts after oil quenching and doesn’t take all the oil together with water into the tempering furnace. That saves money in maintenance and guarantees stable processes and quality. The perfect cleaning before the hardening process ensures cleanliness till the end. Otherwise white spots would stay on the parts and could cause soft spot faults.

Not new but pretty much upcoming are cleanliness specifications which show max. particle sizes (automotive parts), min. surface tension (before brazing) or final carbon residues (medical applications). We could not be happier about this development but unfortunately customers do not understand that sometimes the relation between costs and benefit fail.”

Tying in with the question above, by process where do you sell most of your systems in the heat treatement industry? As an example do you have a lot of systems in plants operating batch IQ (sealed quench furnaces), or is it more to firms doing nitriding or vacuum heat treatment?

“The cleaning machine process must always match to the hardening process hence we sell our machines for any process. In the beginning most cleaning machines were sold for batch IQ because cleaning off oil with water was a mess and customers wanted to have a stable quality. We substituted hundreds of washers in existing lines with our hydrocarbon systems in the last more than 20 years. Years ago optical issues in gas and plasma nitriding process came up and customers requested perfect pre-cleaning. Our hybrid cleaning systems which are using hydrocarbon and water in the same system made it possible to offer spot-free pre-cleaning without the necessity to continously maintain and exchange the cleaning bath.

By the fact that especially commercial heat treaters offer a wide range of processes, our machines are also able to cover the cleanliness demands of all these processes because investing in a cleaning system unfortunately still is an investment with very low financial return.  It is only valueable in case the customer can offer better quality and can use it 24/7.”

Could you tell us what different types of cleaning systems are available on the market?

“I think most systems are still water-based spraying type systems with circulation air drying. More and more they are substituted by flood washing machines with vacuum drying unit. These flood washing machines can be water-based, solvent-based or a combination of both. These machines can be loaded from the top by crane or from the front by loading carriage. In addition these machines are available as continuous throughput systems.”

In a past life I sold vapour degreasers which in my opinion were and still are one of the best cleaning systems in the world. However because of health concerns related to the solvents being used they have largely fallen out of favour. Out of curiousity are there many of these systems still in the industry?

“Yes there are many of the old open top vapour degreasers on the market which cause cancer and harm the environment. Most run only by using a special permit because the operating company believes that there is no proper substitution on the market.  But depending on the execution and the used cleaning agent these machines are not harmful to humans or the environment and we also build them for e.g. aircraft applications. They are just cheaper than the flood washing machines and in some cases the cleanliness is good enough. Important to know is that we heard next year the EPA will release a list containing these halogenated hydrocarbons with the effect of proscriping them soon. Your readers operation a machine like this should be aware of that.”

Ok solvent vs; aqueous cleaning systems, what are the advantages and disadvantages of each?

“There is a very old chemical rule being called “like dissolves like“.  Anorganics like water-based emulsion or coolant, fingerprints or salts cannot be cleaned off by hydrocarbon. You will always see white spots on the parts which could be soft spots as well. Organics like quenching oil can be cleaned with water but the water will be polluted and must be exchanged quite often to have a stable quality. That’s the reason why organic solvents like hydrocarbons should be used. The residues are solved much better and the by boiling point the oil can be distillated and the hydrocarbon never has to be changed.”

Did you ever wash a pan with fried oil and afterwards a wine glass in the same bath in your bassin? How clean was the glass?

“If we respect the rules of nature things are getting done much easier.”

This might be a rather provocative question but I am going to ask it anyway. From personal observation it appears to me that Europeans are far more obssed about cleaning than North Americans, perhaps more than they should be. You do business all over the world, what are your thoughts?

“Cleanliness is of high importance because everybody wants to reach his destination by car, train or plane without interruption. Everybody wants to have clean medical implants which will not cause pain before the surgery is even healed. There are so many reasons why we should appreciate the positive effect the cleaning industry has but of course people sometimes feel that it is too much. And this obsession is real but it is mainly caused by the automotive industry not by nationality. The automotive industry all over the world tries its best to prevent any problem that can occur. Hence if a problem occur when a metallic particle with 200µm is in the fuel injection system, next time they ask for max. 100µm size.

We are working in the fine and ultra-fine cleaning business as well and when you see that the demands on a mechanical design can never be reached in reality it is really hard to understand for us why nobody stops this situation. The gap between the desirable and reality is widening and to reach the required specifications the whole manufacturing of a car must be done in a clean room.  To be honest, we know how to handle it and others don’t hence we have a profit from this obsession. Nevertheless we try to give our feedback in order to stop the widening of this gap because these things cause costs and finally all of us have to bear them when we buy the final product.”

How do you handle sales outside of Europe? For instance do you have offices in Asia or North America?

“In China and India we have sales and service offices as well as license manufacturing for hydrocarbons cleaning machines. In some other Asian countries we have sales agents who are mainly selling furnaces or coating machines but also know about the importance of cleaning and see our products as additional equipment.

In North America we have a Joint Venture with sales, service and license manufacturing in Queretaro, Mexico. They are taking care of our machines in Mexico, USA and Canada. Outside Mexico we mainly work together with the furnace manufacturers by projects and we exhibit at the usual trade shows. For the US market we are open to discuss in case readers would like to work with us.”

What do you see in the future for your systems as it relates to the heat treating industry? Do you see a shift to more additive manufacturing which would insinuate smaller cleaning systems or do you see the opposite, meaning larger systems?

“In LPC we see that very small batch sizes are coming up which is interesting for us and we already developed machines for that. Additive manufacturing is very good for us because these parts are like sintered parts and you need vacuum to get them cleaned. We have a lot of experience with those parts. Similar thing is the substitution of the cast racks to CFC racks. They are very light and you can have much more parts in the same batch but cleaning without vacuum is impossible. We made a lot of trials for a customer who is now using our hydrocarbon system.

Last year we developed the first solvent vacuum cleaning machine for roller hearth furnaces because the customer wanted to quench in oil and not in salt. Every 7,5 minutes he now cleans and dries a batch in conjunction with his furnace. My company is very innovative and we love to spend time on developments with our customers. Doing the same every day is just boring.”

I appreciate the time Andreas, Thank you, Gord