Metal processing machinery retrofit
• Machines • Technical Articles • South-East European INDUSTRIAL Мarket - issue 4/2008
Metal processing machinery retrofit
The leaders in the sector discuss the condition and perspectives for market development in Bulgaria
Much can be said about this market niche. All about the condition of machine construction in Bulgaria between 1989 - 2008. Below you can read about the most interesting and important things that can be said about the retrofitting service in Bulgaria, by the people that know best what it is and if there are favourable conditions for its development in the following years.
Higher efficiency machines are being modernized
The market segment of metal processing machinery rehabilitation and modernization will always exist. The question is what types and models of metal cutting machines are economically justified to be modernized. In comparison with previous year the number of annually retrofitted machines is going down. If measured as monetary flow/turnover, there is probably no change; even growth may be possible, since higher-efficiency machines are being modernized.
A significant growth in this segment can hardly be expected. In most European countries, this is a very stable segment without drastic changes. There is no reason to have a different market situation in Bulgaria. As I have already said, mainly good machines of the middle and upper class will be retrofitted.
Impact of our EU membership:
Of course, Bulgaria’s accession as an EU member has had an influence on this segment. The increase in labour costs makes the modernization of small and low-efficiency machines almost pointless, compared to the new models of the same class that are offered on the market. On the other hand, in order to be competitive, the Bulgarian manufacturers should retrofit machines and achieve good performance. Modern CNC, drives and measuring systems should be used for this. We are now witnessing this process. In some cases this is the better solution for the Bulgarian manufacturer than the alternative to buy a new machine.
Technical trends in retrofitting:
We, ECD Bulgaria, as a representative and service of HEIDENHAIN, offer the full range of retrofitting solutions that have the same properties and functionality as the fully digital models. For example our highestcontrol class is offered as an analog version. Another model is intended specifically for machines of lower and middle class, and a third one, for CNC lathes, is also is offered as an analog version. The companies, dealing with retrofitting, probably know that our product range also covers the full range of digital drives but with analog interface as a customized item.
With everything said so far, I would like to emphasize that the retrofitting solutions offered by the leading companies in the field of machinery control are not some kind of compromise with the offered characteristics and functionality. Our objective and aspiration is machines, retrofitted with similar modern products, to be as close as possible to the characteristics of a new machine. And in this, we and our colleagues in the sector differ substantially from the many other compromise solutions for retrofitting, offered in our country.
Eng. Stefan Michev, CNC Manager - ESD Bulgaria
Good quality retrofitting cannot be made by any company
What is retrofitting actually – some cheap partial repair of the equipment or its full rennovation and modernization? Who can do this and to what extent are we ready to pay the high price of real retrofitting? What is the optimum limit for expedient investment in repair work? Shouldn’t we buy new equipment instead of investing money in unclear solutions with temporary effect? Everyone should be able to answer these questions if they have made good planning and have a good vision for their business.
Right now, clients in Bulgaria are still trying “the gound” and are hesitant whether the buying of new machinery or the repair of old ones is the better solution. It all depends on the solvency and on the manager’s view – smaller companies with limited budget prefer retrofitting and the reason for this is more than obvious. However when we speak about the condition of this market segment, we should not ignore the fact that not every company or separate person can carry out retrofitting. There are companies that say they do retrofitting but this is far from the truth. They work for less money with less staff and less invested funds. They state and even warrant before the client that the machine repaired by them will be in good condition, but in practice its parameters are far from the values typical of a properly repaired or an almost new machine –high spindle speed and revolutions, stability and reliability of the mechanical part, corresponding to state-of-the-art cutting tools and modes, quick response and reliability of the electric control, etc. Most of them do not even have the most necessary measuring devices and equipment required for precision monitoring. The compromises that these repair persons make turn out to be very expensive in time. Not to mention that the wanted increased accuracy, reliability and fast operation of the machine have not been reached at all. Often clients want “only to have their system replaced, the machine itself is almost new” – but this is not repair, this is not even good investment, it is only a cosmetic change. In a year the client will understand that he has to give money again! Why pay twice?, I am asking.
Quality costs money, good quality costs a lot of money
The actual repair work is more expensive but machines get improved characteristics. What is left of them is practically the housing elements and main assemblies, however their concepts and basic structural solutions cannot be changed. The Bulgarian and imported machines that are still in operation are quite obsolete, in the general case they are models dating back 15 - 20 – 25 years. Through repair they can reach a technology level up to the end of the 90-ies. If more money is spent, a level corresponding to 2000 - 2001 can be achieved. If we assume that the level of metal cutting machinery technology is updated every 5 - 6 years or less, the achieved level is entirely sufficient for our manufacturing needs.
The technical parameters of machinery of latest generation could not be obtained by retrofitting. We should bear in mind that feeding speed, which is considered highest here, e.g. 30 - 40 m/sec. , is already a standard in the new Japanese, Asian and European machines. Spindle speed of 8 000 - 10 000 rpm for the centers and 6 000 rpm for the lathes is already a standard. Such parameters cannot be reached via retrofitting – their mechanics simply wouldn’t cope. The control systems and the electric equipment dating back to the beginning of the 80-ies of the last century are entirely unthinkable. The new machines are multi-axis, fast, high-efficiency. Linear drives, integrated spindle motors, ball pairs with screw cooling, thermal compensation of the housing elements, special measures for cooling and thermal regulation, fast shops for tools and pallet changers and many others could be provided only by a new machine.
What is more - in the West, and even East, real retrofitting is made only in factory conditions, mostly in the factories in which the machines are manufactured. This is so in German, Czech and Polish factories, as well as in Japanese, Korean, American and even Serbian factories. The factory’s most experienced staff with many years of practice is concentrated in the repair workshops there. It is supported by structural, technological and metrological units and departments, technical documentation, spare parts warehouses, logistics. There is no compromise with quality there, the machines come out with factory warranty and company servicing. Yes, but the prices are “fierce”! In our country this is unthinkable at this stage, simply there are no factories there.
It is very difficult to predict at what rates will this market segment develop since this is a transient, I would even say, crucial moment for machine construction. The managers of enterprises understand the need of renovation of the machine stock – so money will be invested in this. I believe that the amount of repairs will stay at the present level and will even increase. The change will come with higher requirements to the retrofitting – they will be more and more demanding because the requirements for the machines are greater. A proof that such repairs will continue to be carried out in Bulgaria is the emerging of new players in the repair field.
I also expect that the procurement structure will change. Presently there is interest in the repair of big heavy machines. The new models are very expensive and therefore clients will turn to retrofitting old ones. About small machines – they are doomed. For them the price of actual repair is getting even closer to the price of a new machine. On the other hand, even the companies that are known in the filed of retrofitting do not sufficiently possess the necessary conditions for effective completion of such large-scale repairs. This requires not only heavy equipment and large halls but also specialized qualified staff which is becoming more and more difficult to find.
Impact of our EU accession:
A connection could be identified between our EU accession and repair services. It would relate to the possibility of finding relatively “new” machines in the European countries. The reason is the well developed leasing practice – each European manufacturer, as a rule, aims at working with new machinery. After the leasing period is over, the machines are usually replaced but they are still in good condition, 4-5 years old, although intensively operated. The warehouses for second-hand machinery in Germany, Italy, France are full with relatively “new” machines – our entrepreneurs could buy such. However, I would like to point out that this does not make repair unnecessary, since in most cases these machines also need renovation, although not considerable. Of course, there is danger to see the story with used cars repeating – we should not turn our workshops into old machine graveyards. Turkey suffered from this syndrome 15-16 years ago, when it imported massive amounts of obsolete machinery from all-over Eastern Europe but now it holds one of the first places in the import of new machinery – almost as much as whole Europe. Of course this was regulated by its state via strict customs restrictions.
Technical trends in the retrofitting:
So, what do you want – partial repair or full retrofitting?
If you want retrofitting, you should request and supervise the full deinstallation, inspection of the hardness and regrinding of the guides. Also carriage fitting with antifriction tape, but with a genuine one, such as the tape used by the manufacturers of new machinery, delivered by real manufacturers, not one of plastic material. Then the carriages are matched to the guides; you should ask how many spots have been reached per square inch. This ensures that dimensional and accuracy parameters, as well as cohesion comply with the ones typical of a new machine. It is almost always necessary to replace the ball-screw pairs with new ones, or, if the old ones have residual lifetime, additional tightening should be performed, but this should be done carefully, since the wear limits are two close. It is necessary to replace all bearings, with no exception, by using bearings of well-known manufacturers, especially the spindle bearings with factory prescribed accuracy. 100% of the hydraulic equipment is repaired, new pumps, distributors, pipes and new sealing elements of the hydrocylinders are mounted, as well as all the elements, participating in the oil system – units, partitioning devices, joints. The replacement of the knife holders, the universal and hydro tightening cylinders with new ones is recommendable – old ones cannot be repaired. The rotating tables are either reconstructed or replaced with new ones. The tool shops are in desperate condition therefore they are replaced with new. The guards and especially the chip collector bins are totally used-up and they require complete restoration. In some cases it is more expedient to replace or reconstruct the machine enclosures completely – crushed or torn welding or crushed or missing glass (hardened or triplex by all means), otherwise cooling liquid will leak from the machines and chips will be flying all over the place. Not to mention lacquer coating.
The machine’s electric installation and its control part should be replaced completely. The control system, the motors and servo units may not be latest generation, however it is in your interest to get them from a well-known and reliable manufacturer with guaranteed servicing, and not get a cheap duplicate, do-it your-self equipment. The electric cabinets should either be replaced or serious measures for their cooling should be taken, otherwise they will explode and ignite. The electric cabinets should be constructed anew by observing all modern requirements for them. The electric equipment also has specific lifetime and it is not very long, especially for Bulgarian equipment. The cables have lost their flexibility and should be replaced completely along with the necessary cable ends and marking, as well as the cable guides and suspension. The control panels should by all means replaced with new ones, their location should complied with new ergonomic requirements. The signs, plates and inscriptions should by all means be new. All plates on the machine should also be replaced as per the safety engineering conditions and standards. The new European safety engineering requirements, such as door movement interlocks, work in closed work space, lighting in the work zone, ventilation and oil vapour removal, separation of oil drops from the cooling liquid, earthing and neutral earthing of the machine, galvanical separation of the power supply, etc., should be observed.
In the end, the protocol of accuracy standards should be prepared according to the passport, and the parameters set by the manufacturer and even higher parameters should be acheieved. This must be verified with respective attested instruments, devices and appliances. The machine should be accompanied with the respective documentation including all entered modifications, new elements, specifications for spare and fast-wearing parts, electric diagrams, ladder diagram, etc.
This is real retrofitting. Everything else is a compromise. If you do not like it – find another repair company. It is your decision and your money.
Eng. Svetoslav Lazarov, LAZATEK company Manager
Old machines can hardly compete with the new ones
Our assessment of the present condition on the market of activities related to rehabilitation and modernization of metal processing machinery in our country is that the sources of old machines and technologies have become less in number and strength, and that interest in them is being lost.
We believe that this market segment will mark a temporary slowdown in the near future.
Impact of our EU membership:
Of course, Bulgaria’s accession to the European Union has an impact on this market segment in our country. Many of the Bulgarian companies get serious orders for manufacturing various details by EU member states. European employers require compliance with highest standards and application of new technologies. This would mean the use of high efficiency and accurate machines which has an effect towards the weakening of the market for recycled metal processing machines.
The modernization of old machines is mainly in the direction of implementation of new systems for control, new drives and new positioning systems. It is very difficult, however, such a machine to compete with the new models.
Eng. Kalcho Kalchev, Machine Commerce
Modernization is justified for large-scale and unique machines
The modernization of metal processing machines, called also retrofitting, has been developing with different speed and direction in our country during the last 15 - 20 years, mostly depending on the specific economic conditions. In the first 10 years of economic transition, there was a great number of offered machines, manufactured mainly by the former socialist countries. In this period, the demand on the market of metal processing machines in our country was very weak and only a few companies performed retrofitting of universal and CNC machines.
With the laying of market economy foundations, serious movement was observed on the metal processing machinery market, including a demand for modernized machines. In this respect, Bulgaria’s accession to EU played a great and led to stricter requirements for quality, efficiency, delivery terms, etc.
The main technical trends in the retrofitting of metal processing machines are:
•Replacement of the machines’ CNC control which is already obsolete and its maintenance is almost impossible. If the machine has a residual physical resource, this retrofitting is completely reasonable.
•In most cases, when CNC is replaced, DC and AC drives are replaced or modernized too.
•The same refers to the displacement measuring, where the used elements are obsolete and unreliable during operation, as well as not sufficiently accurate.
•For many of the machines, retrofitting of the power control system is also completed, including the replacement of physically obsolete electric circuits and elements with new and state-of-the-art ones.
•Modernization should be accompanied with the respective structural changes in the mechanical part with the aim of integrating new and modern elements and solutions.
Each repair requires serious preliminary study of the following:
•The technical condition of the machine, the degree of wear and the respective complex of measures that is required or recommendable.
•The anticipated costs should be analyzed in advance and should be added to the residual value of the machine in order to assess whether they will ensure its efficient use for a period of 5 to 7 years.
•A comparison should be made between the price of the technical indicators of the modernized machine with the new similar models of the lower price class offered on our market.
As a general rule it should be accepted that modernization is most profitable and justified for large-scale and unique machines that have high metal consumption, a high-price, and also require very long delivery terms. For the mass machines of the so called lower and middle class, modernization could often turn out to be a pointless and unjustified technical and economical solution.
Eng. Georgi Belchev, Polimeta S Manager
Operating new machines to keep in step with time
Our long-term experience in the branch shows that presently a growing number of metal processing machines users prefer to buy new machines. This is due to the increasing labour shortage. At the same time the requirements on the market for components and assemblies dictate the provision of cheap and good-quality production. The aim of the investors is to get maximum financial efficiency from the equipment. Old machines, although renovated, can hardly meet these requirements, especially the requirement for greater efficiency.
The modernization of a metal cutting machine could improve only its reliability. But if the client wants to increase its efficiency, the price of the repair will become equal to the price of new machines that we manufacture. And newly manufactured machines have other significant advantages – they have state-of the-art kinematics, accuracy and stability, and are capable of working with a cutting speed meeting the requirements of modern metal cutting tools. The warranty period provided for a renovated and a new machine should also not be ignored. It is considerably shorter for renovated machines and does not cover the whole machine but only the renovated part.
Our observations show that this activity will continue to develop for unique metal cutting machines. In the last years we in RAIS specialize in the processing of big carrousel lathes, e.g. in CNC lathe centers– machines, processing details with diameter over 4 meters. The renovation of unique machines is a challenge and justifies the effort. This is not true for conventional machines. In this case the purchasing of a new machine has a number of advantages.
Impact of our EU membership:
The impact of EU membership is a fact. 15 years ago RAIS started its activity with the recycling of Bulgarian CNC machines but our clients are increasingly starting to rely on new production. In order to be in line with time and with the European quality requirements, we should manufacture new machines and use new machines.
Bulgaria’s stock of old metal processing machines is too old, and the renovation of machines manufactured before 1980 is not profitable, unless it refers to a really unique machine.
Technical trends in the retrofitting:
Unfortunately, our observations are a small number of the companies now starting in the sector take the wrong path of using renovated metal cutting CNC machines with components having unprofessionally manufactured electronics, drives and measurement sensors produced locally. At a first glance these seem comparatively cheap and the repaired machine gets a good price, but afterwards, they cause serious problems for the machine user. Unfortunately the investor becomes aware of this after having paid for the equipment, since with such components you can get a machine for learning purposes but not for professional production. For a company that is just starting, it can be more efficient to get an old machine, but only if does not get regular orders. If orders have to be completed precisely and within a specified term, it will be better to buy a new machine. If an old machine is however selected, the clients should be extremely careful about the quality of the renovation proposed to them.
In RAIS, we insist that even the training of new specialists should be performed on new machines and therefore we have provided the Technical University in Plovdiv with a new vertical processing center with CNC and lathe. Our wish is future experts to be taught with the latest, most modern and compliant with European requirements equipment.
Nishan Bazdigyan, Manager of RAIS - Pazardjik
EU had a global impact on the sector in a positive direction
The market of the activities, related to the modernization of metal cutting machinery is related directly to the condition of the metal processing industry. Currently all prerequisites are in place to say that retrofitting is in real boom and has overcome the crisis, typical for the 90-ies in the end of last century. More industrial companies are becoming increasingly active and are looking for companies to modernize their equipment. They wish of course to have their old machine stock made more reliable with modernization of their machine control system and completion of the required mechanical repairs. In this way the machines will be more efficient and profitable and the companies from the sector will be able to plan their production volumes better.
Unfortunately some of the companies, dealing with retrofitting, have reduced their activity in this field and have increasingly been developing activities as representatives and service partners of foreign manufacturers of metal cutting machines. As the Engineering review magazine readers are probably aware, machines from Europe, and of manufacturers from Asia – Taiwan, Chaina, Japan and Korea are offered on the Bulgarian market.
In my opinion, the trend in the development of this business segment is directed towards gradual focusing on the modernization of non-standard, large-scale and unique machines. The reasons are economical – for machines of this class the prices of new equipment are high and the delivery terms respectively are long.
Impact of our EU membership:
I do not see grounds to believe that Bulgaria’s accession to the EU will considerably influence the business and the companies involved in modernization. The European Union has rather had a global influence on the sector in a positive direction by facilitating the work of the companies with their partners and suppliers from the community – better logistics, easier work with customs, etc.
The trends in the modernization of metal cutting machinery are directed at the use of CNC-controls with modern visualization, facilitating operators and process engineers in their programming. State-of-the-art controls offer graphic templates for easy and fast programming of the basic technological cycles and loops. The options for modern communication between the programming stations and the machines, connected in a network, should also be noted. The replacement of all servomotors and drives with contemporary models fitted with digital control together with the control itself, is now done more often.
Eng. Petar Katsarov, CNC, Sales Manager, Industry Division, Siemens
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