Please tell us more about LMT Tools , its product range and innovations…
LMT Tools is based out of Oberkochen, Germany.  It is a family owned small and medium enterprise.  As a group we have four principle brands LMT Fette, LMT  Kieninger, LMT  Onsrud & LMT Belin. Two of these brands come from Germany, one from France and one from the US.

The products we are concentrating on are niche and highly focused in specific areas.  e.g. the products manufactured in Fette at Schwarzenbek, close to Hamburg are essentially the tools which go to produce gears .  Under this brand LMT Fette, today we are ranked amongst the top 2 or 3 global companies and within Europe, we are certainly the No. 1 supplier of hobs for this application.  In this product program, we have the complete range in both materials and modules-  starting from powder metallurgy steel to solid carbide to the indexable version and  from Module-1 to almost up to Module-50.  In short, it’s not just the automotive industry that we cater to, but also general engineering and Energy sectors. To give you an insight into the various developments and innovative initiatives of the group, our Speedcore, probably stands out – essentially this has come out of the advances made in the material science in combination with variety of its heat treatment and coating apart from our manufacturing technology making it unique. This product is able to achieve attractive speeds and feeds substantially higher than any other competitor in this classification thereby ensuring the productivity for the customer is always met

The other product line that comes out of LMT Fette is the unique Thread Rolling System where we certainly claim the pole position globally.  Here, we have set the benchmark for range and applications and are the preferred suppliers to many internationally acclaimed end users.

If I move down the third line which comes out of LMT Fette, it would be the Round Tools in the field of High feed milling and special Solid Carbide End-mills for the aerospace industry and the medical industry where the product is carving a name for itself.

Moving on to the LMT Kieninger range of products you will get to see the complex tools which are predominantly used in production of automotive industry specially –

• line boring bars which are needed to produce Crank and Cam bores-
• Cylinder boring bars
• Tools to produce spherical shapes.

We are easily among the top three suppliers of these tools and are working closely with most of the machine tools manufacturers and end-users. We have a reputed list of customers from the machine tool industry and end users, mainly German companies like BMW, Daimler and Volkeswagen amongst others.

We have managed to share the same technology with quite a few companies in India, Renault for example, have been testing our products and are quite happy with it. We have also supplied to Cummins, TATA and Ashok Leyland being our  principle customers.

Moving on to other brands- LMT Belin, we have a range of reaming tools which involves high precision and our manufacturing technology from this French company stands out in the product. Our other range of product is LMT Onsrud, where we supply predominantly to the aerospace industry -so for machining of composites, honeycombs and host of other applications, especially for exotic material like Inconel, Onsrud range does a brilliant job.

Can you please explain about the Indian operation?
We have the manufacturing base in Chakan, Pune where we produce hobs and catering to the Indian automotive industry from motor-cycles and scooters all the way up to cars and have graduated including trucks and tractors.  We are expanding the manufacturing programme to round tools and gradually we will be moving into other tools as well, as and when we see the necessity. The reach and go to market approach has given us lot of confidence having established Centers of competence for gear cutting, milling, tapping and thread rolling – here we have most of our engineers trained in Germany, thereby ensuring we offer performance solutions to the customers in sync with what they exactly want.

Tell us more about your R&D activities. What percent of your revenue goes into R&D?
As a group we believe in constantly innovating. We intend to constantly bring out something new every year in the respective areas we are operating. For example right through last year we introduced a totally new product in the field of gear cutting. We brought in the CarbideLine, SpeedCore and ChamferCut.   As for   motion tools from Kieninger range, we have been constantly innovating to come up with   new geometries and new special designs – “Copy max2”   to ensure that the  customer always benefits.  So to answer your question, the group spends an average of 4-5% of the revenue on R&D.  Each of these individual companies have their own engineering teams and development centres. There is one coordinating head from Schwarzenbek who ensures that we are all constantly listening to what customer wants, be it from the emerging markets of China and India or the matured markets of Europe and America.

What are the new technological up-gradations coming in?
We have worked on two areas.  When it comes to carbide technology we have been working closely with our carbide suppliers to ensure that the latest trends are provided for us depending on the application like steel, cast iron or stainless steel or exotic materials. For example, what we are doing with respect to Aerospace industry, we have come up with very very latest generation materials, but that apart we have our own in-house coating team which is constantly working towards new ranges of coatings to be brought in,  e.g., nano-mold, nano-spehere etc.  Now coating by and large is not enough on its own.  We have also developed substantial technology from manufacturing perspective especially with respect to edge rounding and de-burring and host of other areas, thereby ensuring that the advancements we make both in the substrate and coating is translated and easily brought on to the  material. If one visits our plant in Pune or anywhere in the world, you will get to see these little, specific advancements in manufacturing technology that have been made thereby ensuring our claim of substantial benefit with respect to the product when it reaches the customer.

Now everyone is talking about green machining and industry 4.0 and technology like IOT. Where does LMT stand?
In most of these areas, we are working closely on Industry 4.0.  Back home in Germany which is where most of these technologies are introduced, our team is working closely with the universities, colleges and the leading companies and we are part of the group with which we try to ensure that as and when such progress is made it gets translated. So if and when a particular market is beginning to see and show demand for such things, we are one of the few, who will not be left behind. We are very much participating in most of these activities; for example,  if you ask me one of the things which you see here whether it is part of Industry 4.0 or not, some of our thread rolling system we have 3D printed covers.  So things like that have started coming in. So we are able to turn around pretty fast, when customer wants something which is highly customised. To sum it when the progress is made at the market end, we are certainly not caught unaware.

What are the challenges that you face in India?
Being a highly price sensitive market, the basic challenges are always there because most of our products are imported. So we have to necessarily combat with the additional cost associated with importing and the duties amongst others.  The speed with which we are able to bring it in is also a struggle for us.  So our time to market becomes a little more constrained.  We are trying to overcome this challenge by manufacturing it locally and making the products cost competitive. We are now confident that the challenge of producing such high end precision tools exactly to our stringent German and global standards can be overcome thanks to our experience over the past three years

But most of your competitors are also producing in India.
Exactly.  So which is why I am saying when we started producing gear hobs, we have been able to distinctly show that we are able to retain the technology which is produced in Germany and at the same time offered to the customers with the cost competitiveness of products produced in India and in short the customer gets the best of technology and best of price.

What is your strategy to enhance or increase your market share in India?
One simple answer would be, the centres of competence.  In this matrix structure of sales and product specialists who form the centres of competence, we aim to ensure a right blend throughout the sales process.  The sales engineers or sales teams are well qualified to identify the opportunities and the likely pains the customer is facing then the specialists from centres of competence would step in quickly to give the right solution and   therefore, the customer is able to quickly see the benefits and features which we have – both from the knowledge and the product – by this approach we should be able to gain substantial penetration.  We started this exercise in the first half of last year and we have already begun to see sizeable traction in the fourth quarter of last year.

What are the emerging sectors in India?
We see aerospace gaining quite a bit of importance and with our strong program we find ourselves very much relevant in that sector. The medical industry is another one that is gaining greater amount of importance. Within the Energy sector we have seen some resurgence in the Wind Energy and the need for newer technologies. Within automotive sector itself, with the advent of the latest generation of machines coming in, we are beginning to see sizeable interest in the new generation cutting tools – for example in gear production, the manufacturers having brought in latest technology machines which has a high throughput – so we have had to step in to give them the latest range of tools to meet the expectations of both machine and customer.

Your future plans in India…
We plan to expand our manufacturing base in India adding the new products to our manufacturing program. And we aim to increase our market share with the focused approach already explained.

by Nishant Kashyap

At the AMB in Stuttgart current trends such as digitized production, Smart Factory, additive 3D printing, resource and energy efficiency, and lightweight design with the related tool and material concepts took center stage as expected. But the traditional tool blade has not been forgotten. New geometries, cutting materials and coatings are the direct contact to the workpiece and are still govern quality, process reliability and, of course, production costs.

Here, the machining of final contours – finishing – has gained particular importance. This applies especially to components with surfaces which perform an important function, such as workpieces used in die and mold making. Here, the smallest of surface defects can have a direct impact on the final product, e.g. visual defects on body parts.
Roughing as a general pretreatment has not gone out of style. But this preliminary process started being replaced some time ago by near net shape technology and, more recently, by additive 3D printing.

The latest milling tools in LMT Tools Group’s large product portfolio can display the finishing potential possessed by innovative tools when it comes to a wide range of processes from the milling of hardened materials to the production of top grinding quality.

High-performance coatings – the key to service life and precision
High-performance coatings have a fundamental significance for machining: The coating has the closest contact with the workpiece and is therefore primarily challenged by force and temperature influences. Coating systems thus have a substantial productivity potential. Consistent development of application-specific high-performance coatings is a core competence at LMT Tools.

The high-performance coating Nanomold Red was specially developed in the coating center at LMT Kieninger (image 1) for the finishing of cold and hot-working steel, cast steel and hardened materials up to 65 HRC. Its 4-layer coating structure ensures top-quality coating adhesion, while heat is kept away for as long as possible – evidenced by long service lives.

The application area of the Nanomold Gold coating is on the left side of the diagram (image 1). It is the first choice for roughing and semi-smoothening of materials in the lower hardness range.

Another innovative example is the new “Nanomold Black” coating, which was presented for the first time at the AMB trade fair in Stuttgart. It has a performance spectrum between the two established high-performance coatings “Nanomold Gold” and “Nanomold Red” and covers a more universal range of application. Nanomold Black is ideal for smoothening and semi-smoothening steel, cast steel and cast iron up to a hardness of 56 HRC and can be used for both wet and dry machining.

HSCline SuperFinish2 and SuperFinish4 – top-quality hard milling

In addition to process reliability, a high surface grade and long service lives are essential for high cutting speeds when it comes to finishing. The VHM copy milling cutter HSCline SuperFinish2 sets new standards in exactly these areas, especially in the finishing of hardened steel between 56 – 65 HRC. Due to its high-precision cutting edge geometry with an optimized cutting edge preparation, significant tool life improvements can also be realized.

The new copy milling cutter HSCline SuperFinish4 by LMT Fette (image 2) was presented for the first time at the AMB. It has 4 cutting edges with a special S-cut. Compared with the already established HSCline SuperFinish2 with 2 cutting edges, the processing time can thus be reduced even more whilst simultaneously increasing the service life. This is particularly useful when processing larger components with a long processing time.

Its high-precision cutting geometry with defined cutting edge preparation enables a productivity increase of up to 40%. The spiral angle of 30° and the carbide shaft reduce the tendency to vibrate. In addition, the high dimension accuracy enables a significant surface quality increase thanks to a narrow radius tolerance of +/- 5 µm. The tool can also be used for the finishing of hardened steel up to 65 HRC and for the finishing and semi-finishing of high-strength steel.

FinishLine Premium – grinding-quality surfaces
The FinishLine Premium program features a larger number of teeth for all diameters above 12 mm as well as a reinforced base body design and the high-performance coating Nanomold Red. With this tool, users have a milling system which can produce grinding-quality surfaces. The grinding process is substituted, and finishing time and costs are reduced.

Its performance can be demonstrated with a practical example. The surface of a die for the car industry was processed using the material 1.2379 (X160CrMoV12) with a hardness of 58 HRC. The screw miller with a diameter of 32 mm (image 3) was used for this process. The inserts have 1 mm corner radii, the tooth feed is ft = 0.1 mm, and the cutting speed is vc =140 m/min. The final milling result, with a surface roughness of Ra = 0.09 µm, is impressive.

Tangential insert position – highest metal removal rate

For now, preliminary roughing will, of course, remain relevant. For these applications, tangentially positioned inserts, for example, guarantee an extremely stable milling process and facilitate the highest possible metal removal rate during roughing. If the insert geometry also has a positive rake angle, this soft cut also protects machine performance and increases tool life. LMT Fette combined these two advantages in two of the shoulder milling cutters at the AMB and generates maximum steel and cast material roughing and semi-smoothening productivity with the MultiEdge T90 PRO4 and MultiEdge T90 PRO8 designs.
The inserts in the MultiEdge T90 PRO4 have 4 cutting edges and feature an especially stable geometry which is simultaneously soft-cutting, allowing maximum axial infeeds of ap = 11.5 mm to be achieved consistently, even with larger tooth feeds.

The special inserts in the MultiEdge T90 PRO8 (image 4) have twice as many cutting edges. This increases customer benefit thanks to increased efficiency due to further reduced tool costs. The highest axial infeed is ap = 10 mm with adapted tooth feeds. The inserts in the tool displayed are coated with Nanomold Gold (see image 1 as well).

Both tool designs have specific cutting material alternatives for machining steel or cast iron. The name MultiEdge does not stand for the highly-effective number of cutting edges per insert, however. It stands for the high number of teeth due to the close pitch. This means that the largest tool diameter of 160 mm still has 20 inserts. The diameter palette of these new milling tools starts at 50 mm.

Performance can be demonstrated with a practical example. Components (general mechanical engineering) made of GGG50 were machined with the MultiEdge T90 PRO8 with the diameter d1 = 100 mm, the number of teeth t = 12 and a tooth feed of ft = 0.35 mm. The metal removal rate and service life were more than tripled, and machining time and machine costs were reduced by 60%.

Content and Image courtesy: LMT Tool Systems GmbH

The coating of the newly developed CopyMax2 insert from LMT Kieninger is Nanomold Gold, which is already an indication of top performance in mold and die making. But it doesn’t stop there. The copy milling plate itself has an entirely new construction design. It has improved cutting and material properties as well as a fully functional second cutting edge. When the first cutting edge is worn, the insert can be turned over and re-used with the same long service life.

The challenge for the engineering experts was to integrate the second cutting edge into the tool geometry in such a way that the user would be able to mount the milling insert accurately, securely and easily in the tool holder. The solution includes the new conical shaft and a specially designed clamping screw. The tool is available as an end mill cutter or bolt-on milling cutter in the diameters 16, 20 and 25 mm.

Another new feature is that the copy milling plate is manufactured using the High Quality Sintering (HQS) process. With this process, even more stable cutting edges can be achieved thanks to the increased mold pressure and a special design. They are particularly beneficial for the roughing and semi-finishing of large molds as well for removing residual material and enable the machining of large workpiece surfaces with maximum process reliability.

Customer benefits at a glance

• Identical geometry to the highly efficient WPR-AR copy milling plate.
• The absolutely stable cutting edge and proven Nanomold Gold coating double the service life per cutting edge
• Quadruple tool life possible by using the 2nd cutting edge.
• Highly economic solution for more than 70% of your applications in forming technology, energy technology and mechanical engineering.

Trochoidal milling is experiencing a comeback. The foundations for this milling method based on a circular feed motion were laid already decades ago. But it is only through the combination of high-performance tools and machines with the appropriate CAM software that users can fully benefit from the performance potential of this procedure. This applies especially to materials which are particularly challenging for conventional slot and edge milling tools such as higher-strength and hardened materials. Examples of use are the processing of impeller pockets for gas turbines or integral components for the aerospace industry.

The LMT Tools Group cooperates very closely with well-known software companies from the field of numerical control and CAM programming and has been able to confirm the expected advantages of trochoidal milling during use of innovative milling tools. The low cutting forces and their even distribution along the entire cutting edge length allow for higher processing speeds and lead to significantly shorter production times with both increased tool life and component quality.

Much is different than in the past

Until now, high-performance tools demonstrated their ability on the established procedures high-speed cutting HSC, which is predominantly used to generate excellent finishing surfaces, and high feed cutting HFC that serves to remove large chip volumes. Now, the top performer trochoidal milling completes the choice.

Here, the cutter still rotates at constant speed. However, as opposed to conventional slot and edge milling tools, this tool does not perform any linear feed motions with constant chip load during trochoidal milling. It rather moves very quickly on curved paths, the so-called trochoids (figure 1, right). Thus, the tool constantly circulates, approaches the contour of the workpiece, while traveling on a circular path, produces a chip and quickly moves to the next circular path. The superposition of the resulting feed and circular motions has a positive impact on the operation conditions. The chip load f z , the radial depth of the cut ae and the wrap angle β constantly change. The programming system combines theses parameters in such a way that the mean chip thickness and thus the stress on the cutting blades remain constant over the entire process. This avoids an excessive and uneven distribution of force on the cutting blades and the machine spindle.

The maximum wrap angle is significantly smaller than 180°, as it is the case for example when milling a full slot in full cut with a tool diameter that equals the slot width. When using trochoidal milling to cut a slot, the milling cutter diameter must be 30 % smaller than the slot width, in order to enable the circular motion. The reduced width of the wrap angle results in lower cutting forces. This enables the use of a longer cutting blade length, i.e. machining the workpiece in one single pass without changing the axial feed again may be possible. This also saves time and production costs.

The smaller wrap angle reduces both the mechanical and the thermal load on the cutting edge, which, in turn, significantly prolongs the tool.

Moreover, as opposed to conventional milling, where a sudden mechanical stress is frequently imposed on the tool, trochoidal milling avoids this negative effect, when entering the workpiece. The intelligent numerical control of the tool path with a low radial depth of cut allows for smoothly entering and exiting the workpiece. This is, in turn, prolongs the tool life and improves the quality of the workpiece. This smooth method is performed throughout the entire cutting process, which is also beneficial to the surface quality and dimensional accuracy of very thin-walled workpieces

In one example, the wall thickness was only 0.7 mm while the aspect ratio of the tool was large. The material machined was 1.2842 (90MnCrV8) tool steel hardened to 54 HRC. The cutting speed of the solid carbide end mill with a diameter of 8 mm was vc = 440 m/min, the feed per tooth fz = 0,11 mm and the aspect ratio was 2.25. Under these extreme roughing conditions the generated heat was entirely transferred to the chips. As a result, they started glowing

70 % faster with trochoidal milling

The benefits of trochoidal milling described above sound very promising. However, only their respective field of application will prove how beneficial trochoidal milling actually is. A machine manufacturer produces disks made of alloyed chrome molybdenum vanadium steel. During the production, pockets with a dimension of 130 x 55 x 22 mm and a hardness of 48 HRC are also incorporated. The cutting tool used is the solid carbide end mill DHC HARDLINE by LMT Fette that is designed for this specific application (figure 1, center). This solid carbide tool is used wherever high-strength materials up to 1,600 N/mm2 or hardened steel up to 60 HRC are machined. Its unequal indexing ensures maximum balanced running and process safety. It is ideally suited for HSC machining or for trochoidal milling and also comes into its own when milling edges, corners and slots.

The main benefit of the DHC HARDLINE is the excellent surface quality of workpieces and a prolonged tool life compared to comparable competitor products.

In the example described, this tool was used with a diameter of 12 mm and 4 cutting blades. The cutting speed was vc = 300 m/min and depth of cut ap = 22 mm, i.e. almost 2 x D. The maximum wrap angle was 24° at a radial depth of cut ae = 0.5 mm.

The result is impressive. You must witness it yourself, in order to gain a genuine impression of the process flow and the speed of the milling cycles. The processing time in conventional milling was 12 minutes and it was possible to reduce it down to 3.7 minutes. This means time savings of at least 70 %

Also with regard to tool life, trochoidal milling does not need to hide its light under a bushel. While the end of the tool life in conventional milling is usually reached after processing 2 workpieces, there has been no critical tool wear even after 6 workpieces

Nine times faster with titanium

 The performance of trochoidal milling shall be demonstrated on another special example. A 24 mm milled-out portion was to be cut in titanium 3.7164. For reasons of comparison, this was done with the usual strategy using a conventional solid carbide end mill and with the trochoidal milling strategy. For trochoidal milling, the solid carbide end mill DHC INOX by LMT Fette was given a chance to demonstrate its ability. It has a diameter of 12 mm and 4 cutting edges. The cutting speed applied was vc = 140 m/min and the axial depth of cut ap = 24 mm, i.e. 2 x D. The radial depth of cut was ae = 0,6 mm.

The result was impressive. The processing time could be reduced from 28 min with conventional milling to 3 min applying the trochoidal milling strategy

The user benefits at a glance

• Significant reduction of manufacturing costs by high processing speed
• Low cutting forces due to smaller and consistent chip cross-sections
• Reduction of the processing times by at least 70 %
• Increase of tool life by more than 300 %
• Excellent surface quality
• Large axial feed of the tool enables the use of the entire cutting edge length, large aspects ratios are possible
• Slot milling is possible regardless of the tool diameter
• Lower machine load

The most important demands made by the mold and die making industry are stable component quality and surface quality as well as process reliability during production. Furthermore, the shorter product life cycles of the molds also require a permanent reduction of the reaction and processing times. The product launch time must be as short as possible.

LMT Kieninger is the competence center for mold and die making in the LMT Tools Group. In the past, the experts there have developed a complete and highly productive range of tools and are always searching for new, efficient solutions for users.

The innovations focus on cutting materials and cutting edge geometries in the macro and micro ranges as well as customized coatings from the in-house coating center, based on intensive knowledge sharing with users and the tool experts at LMT Fette. At the AMB trade fair, LMT will be underlining its leading position as a partner of the mold and die making industry.

New Nanomold Black coating – universal application range
High-performance coatings have a fundamental significance for difficult machining operations: The coating has the closest contact with the workpiece and is therefore primarily challenged by force and temperature influences. Coating systems thus have a substantial productivity potential. At the own coating center, experts repeatedly manage to create new coatings tailor-made for the respective application.

One innovative example is the new “Nanomold Black” coating, which will be presented for the first time at the AMB trade fair. It closes the application gap between the already established high-performance coatings “Nanomold Gold” and “Nanomold Red” (image 1). Whilst the gold coating is the first choice for roughing and semi-finishing materials in the lower hardness range and the red coating displays its true performance during the finishing of hardened materials up to 65 HRC, Nanomold Black covers a more universal application range. It is highly suitable for machining steel, cast steel and cast iron up to a hardness of 56 HRC.

Nanomold Black is for the various versions of WPR- and WPB- indexable inserts available and also on two different types of carbide: For LCPK15M for semi-finishing and finishing as well as for LCPK25M for roughing and semi-finishing, for both wet and dry machining.

CopyMax 2 copy milling insert – quadruple tool life

The CopyMax product range is a particularly important milestone in goal-oriented tool development. It treads new paths in the production of indexable inserts. Thanks to the high-quality sintering (HQS) process, even more stable cutting edges are achieved using a high press pressure and a special shape. The first product in this series is the CopyMax2, which is the forerunner of this new generation.

The coating of the newly developed CopyMax2 indexable insert from LMT Kieninger is Nanomold Gold, which is already an indication of top performance in mold and die making (image 1). But it doesn’t stop there. The copy milling plate itself has an entirely new construction design. It has improved cutting and material properties as well as a fully functional second cutting edge (image 2). When the first cutting edge is worn, the insert can be turned over and re-used with the same long tool life.

The challenge for the engineering experts was to integrate the second cutting edge into the tool geometry in such a way that the user would be able to mount the indexable insert accurately, securely and easily in the tool holder. The solution includes the new conical shaft and a specially designed clamping screw. The tool is available as an end mill cutter or screw-on milling cutter in the diameters 16, 20 and 25 mm.

The tool is particularly beneficial for the roughing and semi-finishing of large molds as well for removing residual material and ensures maximum process reliability during the machining of large workpiece surfaces.

During milling of a wave section made from cold work tool steel 1.2379, the ball nose copy endmill has already exceeded the expectations of the developers. The cutting speed was 240 m/min, the cutting depth was 1.5 mm and the radial depth of the cut was 0.5 mm. In a direct comparison with an existing copy milling insert, the CopyMax2 insert achieved more than double the tool life: approximately 470 minutes compared to 220 minutes with the same wear (100 µm maximum). But there is also the second cutting edge, which resulted in a tool life which is over four times higher (image 3). A significant leap in efficiency.

HSCline SuperFinish4 – copy milling in top quality

 The requirements with regard to finishing in die and mold making are process reliability, good surface quality and an extended tool life at high cutting speeds. The new HSCline SuperFinish4 ball nose copy endmill from LMT Fette sets new standards in exactly these points (image 4). It has 4 cutting edges with a special S-cut. Compared with the already established
HSCline SuperFinish2 with 2 cutting edges, the processing time can thus be reduced even more whilst simultaneously increasing the tool life. This is particularly useful when machining larger components with a long production time.

Its high-precision cutting geometry with defined cutting edge preparation enables a productivity increase of up to 40%. The spiral angle of 30° and the carbide shaft reduce the tendency to vibrate. In addition, the high dimension accuracy enables a significant surface quality increase thanks to a narrow radius tolerance of +/- 5 µm. The tool can be used for the finishing of hardened steel up to 65 HRC and for the finishing and semi-finishing of high-strength steel.

The preferred area of application of the new HSCline SuperFinish4 lies in the mold and die making sector for creating free-form surfaces, for example, for injection molding and thermoforming tools as well as in general machining. A diameter range of 6-12 mm is available.

Tool technology outlook

With regard to tool technology, more powerful milling tools will be
required due to the increasing use of high strength, annealed or hardened materials. To this end, the development of special geometries, cutting materials and coatings is intensively promoted.

The required process reliability should already be simulated in advance. This requires excellent information and data quality. The “Industry 4.0” initiative of the German industry makes a future-oriented contribution to this. In this context, the additive “3D printing” manufacturing method should also be mentioned. With the appropriate digitally linked equipment, not only models, prototypes and auxiliary tools can be produced at short notice. In addition, there are also new design options with new or improved functions for tool technology. For example, bores “around the corner” enable a more effective coolant supply directly at the cutting edge.

LMT Tools has already implemented various modules for “Industry 4.0” and has also invested in “3D printing” technology.

Rolled threads guarantee maximum strength and resilience in the most demanding situations.
LMT Fette has been developing rolling systems for chip-less thread forming for over 60 years now.

By utilizing numerous individual innovations and its wealth of experience with industrial applications, it has now created a completely new generation of rolling head: The EVOline sets the highest standards for efficiency, process reliability, precision and flexibility in thread rolling.

Whether it is fittings for pipe systems, connections for car bodies, jack screws for houses and bridge buildings or sucker rods for the oil and gas industry, threads are used in practically every sector.
Their job always remains the same, which is firmly holding together what belongs together.

However, there are great differences in the production and quality of threads.
Thread rolling has established itself as an efficient alternative and replacement to thread cutting for three main reasons:
 extremely short production times with the highest thread stability
 constant dimensional accuracy
 excellent surface quality

In addition, a thread rolling head can be used in a flexible way in almost all machining centers.
As a result of its modular layout and a completely new tool design, the EVOline rolling head sets new performance standards for the chip-less production of external threads. This is our solution to the increased demands being made on thread rolling as a result of rising production volumes, new materials and integrated processing on tool machines. It is crucial here that tools offer process reliability, precision, flexibility and ease of operation.

Fine adjustment to accuracy of a hundredth of a millimeter
The exceptional features of the new rolling head include its simple but extremely accurate fine adjustment of thread diameter and the system’s ease of assembly.

Adjustment of the rolling diameter is carried out using a spindle. The system is accurate to one hundredth of a millimeter and offers exceptionally high repeat accuracy of the effective diameter. The new rolling head guarantees the repeatability of the thread diameter with the same setting within a range of +/- 0.01 millimeters. LMT Fette has applied for a patent for its new adjustment system.

Process reliability and simple operation through modular design
The modular design ensures simple assembly. In addition to the thread rollers themselves, the rolling head consists of the roll cage assembly with transmission, coupling with central alignment and fine adjustment as well as flexible coupling joint for a large number of standard shanks, locking mechanism/locking pin and shank. The locking pin can be turned through 360 degrees and therefore optimally adjusted to the mounting situation in the respective machine. The joint between coupling and shank guarantees precise concentricity with secure torque transmission. It can be modified to users’ specifications: for example, a coolant-operated locking device can be very easily integrated as an accessory.

Special chip protection
Special chip protection is another feature that increases process reliability even further. The rolling head has a stable chip protection lid that secures the machine against chips and contamination from upstream processes – even when the coupling is open. The tool design itself – for example, the nickel-plated surface of the rolling head – also contributes to this protection.
Some highlights of all models of the EVOline Rolling Heads
 fast, simple and precise thread production
 short production times, high quality and thread stability
 simple and precise fine adjustment of thread diameter
 permanent protection against chips and contamination
 easy assembly and high standard of safety due to modular design
 trouble-free adjustment to customer-specific applications

Whats New and Updated: 2016
New: The closing process can be realized with the new closing device (CCD) for EVOline. Adapted between rolling head and shank and connected with the coolant supply, closing of the rolling head can be transferred from process time to the non-productive time of the machine. Closing by coolant (or even compressed air) can be integrated in the machine program by a simple function.
The setting of the rolling diameter has adjustments of 0.01 millimeters which allow for precise control and consistent repeatability of the pitch diameter, giving you the assurance of a secure and reliable process.

The modular design provides longevity of use with the ability to replace the thread rolls, rollers, rolling system housing, central fine adjustment, closing clip device and shanks, making it adaptable to any station or other machines in house. All common shank sizes are available.

The interface between the clutch and shank guarantees precise concentricity between the with safe torque transmission. Customized modifications are possible, for example a coolant driven closing device adding to the speed and automation of the entire process.
Huge progress towards increased process safety and reliability is incorporated by a new chip guard in the EVOline heads. Chips and other particles from preliminary processes cannot enter the rolling head anymore, even with the opened clutch.

Article Courtesy: LMT (India) Pvt Ltd

Tell us more about your milling and threading technology…
LMT Tools is headquartered in Germany with manufacturing plants in Germany, France, USA and India. The company manufactures a wide range of cutting tools which includes gear hobs, thread rolling systems, special automotive tooling, milling & tapping tools etc  We also have complete range of tools for for die and mould industry.

How would you describe the Indian die mould industry?
Indian die mould industry is very competitive. The industry is well developed in terms of technology; the facilities available in India can be compared with best in the world. The only challenge I see is the delivery time and the price sensitive market.

Various die mould makers are finding it difficult to compete with companies from Thailand, Korea, Taiwan, etc. Being a tooling solution provider, do you face such competition?
Like the die mould makers we also face competition from various suppliers .We focus on technology and offering complete solution with application support to differentiate ourselves

Other challenges that you have witnessed in India…
I think Indian customers are tech savvy and are open to adopt latest technologies, be it big automotive manufacturers or SMEs. We have  to reach them in time  and offer them the latest technologies .This sometimes takes time but it is a challenge as well as opportunity

Companies from Korea, Taiwan and China have become very aggressive with their cost effective solutions. India being a price sensitive country, how do you manage the competition?
Definitely the selling and marketing efforts go up. If you see any product, be it business or consumer products, all kinds of products are available at different price levels and all of them have a market share. Yes, the tools from these countries  are being used by many customers but there is a huge section of the industry that values what we can offer

India is also home to all big cutting tool manufacturers. How do you tackle competition there?
We have the best of the technology for the cutting tools which is widely appreciated  in Europe and many other markets .We introduce these tools in India as early as possible.  We  have trained manpower who are able to demonstrate the end-users about these technologies. This  coupled with customer support helps us to tackle the competition

Tell us about your R&D activities?
In cutting tool industry new geometries and coatings matter the most. We have a very strong R&D team in Germany  who are continuously working on new geometries and coatings ,designs

Your future plans for India…
We  have a manufacturing setup in India for gear hob manufacturing. We are looking at various other products which can be manufactured in India.

We have strong sales network consisting of our own engineers and channel partners and through them we will be continuously working to enhance our offerings .

The German tooling giant is displaying its expertise in Die & Mould Industry at ongoing Die & Mould India International exhibition. The company is highlighting its High Feed Indexible and Solid Carbide Tools, Double Helix End Mills, Ball nose and Bull nose cutters, and inserts for roughing & finishing, High Power Milling Chucks & Shrinkfits, Tool Extensions and Table Top Thermogrip Machine.

The event is scheduled from April 6-9, 2016 in Bangalore International Exhibition Centre, Bengaluru. LMT Tools is showcasing some of its high-end products like Multiedge 2 feed Mini, Multiedge 4 feed, Multiedge Double 4 feed, 2 feed & 4 feed solid carbide endmills, Finishline premium, Univex Premium, ACU Jet Double 6, Ballnose copy cutters for finishing & superfinishing, Double Helix Endmills and Nanosphere red coated endmills from its Stall B-50, Hall 2A.

Product Highlights:

MultiEdge 2Feed Mini: Small Cutter with Big Results

• Cutter permits maximum material removal rate even in less powerful machining centres.
• All new high performance cutter for machining small and medium components.
• 2 different insert geometries with 2 different cutting material types ensures that almost all materials used in tool & die making can be processes.
• Advantages include: High material removal rates, high performance & high feed geometries and Internal coolant supply

DHC Hardline: End Milling With Full Hardness

• The DHC Hardline extends the family of solid carbide end mills with different helix angles (Double Helix Cutters).
• The special geometry ensures maximum productivity in a smooth running and stable process.
• The high resilient cutting material of the DHC HARDLINE allows machining high strength materials up to 1600 N / mm² or hardened steel between 45 and 55 HRC. Additionally it can be used in cast iron too.
• Advantages include: Highest process reliability in high strength materials, drastic increase in tool life, one single tool for roughing and finishing, proven geometry (DHC) for maximum smoothness, real life miracle in softer steels

SuperFinish: Dimension for Precision

• The latest SF (super finish) geometry sets a new standard for process reliability, surface quality, and tool life, thanks to high precision cutting edge geometry with an optimized cutting edge preparation.
• Used for finishing and semi-finishing high strength steel.Can be used for components with very long machining times.
• Polished cutting edge with high precision cutting edge preparation for high process reliability even in manless production.
• Very high dimensional and indexing accuracy.
• Advantages include: Reduction of machining time by 25%, no rework after replacing the indexible inserts, significantly reduced tool costs, mould and Die optimized grade, Nanomold Red

LMT Tools group, leading cutting tool manufacturer, is presenting in Milan tool innovations for more productivity. Faster, more efficient, more flexible – the requirements with regard to the machining of modern industrial materials are diverse. Numerous solutions that can effectively boost the performance of existing production processes will be presented in hall 10, stand D12/E11. This applies to high-performance milling, threading and rolling in the same way as to gear cutting, drilling, reaming and turning.

The SpeedCore hobs are now even more powerful

The LMT Fette SpeedCore hob has established itself as a specialized high-performance production tool for toothed wheels – for example in vehicle transmission systems. By integrating an innovative cutting material that uses so-called intermetallic phases, the hot hardness of the SpeedCore is significantly higher than that of PM-HSS substrates. The outstanding performance of these tools has now also been transferred to larger tooth systems. As a result of this development, hobs are now available up to module size 20 (diameter 250 mm) (lead image), which are used, for example, in transmission systems for commercial vehicles, heavy machinery engineering and wind turbines. In addition, a higher evolutionary stage of the previous coating Nanosphere 2.0 was achieved to increase the temperature resistance once again. With the new coating, called “HT” (high temperature), the distance between the SpeedCore hob and the carbide is reduced even more with regard to its machinability properties.

HT” (high temperature), the distance between the SpeedCore hob and the carbide is reduced even more with regard to its machinability properties.

Thread rolling – now even faster

Thread rolling systems are part of the important core competencies of the LMT Tools group. The proven user benefits of thread rolling compared to thread cutting are extremely short production times combined with highest thread stability, constant dimensional accuracy and excellent surface quality. Very recently LMT Fette launched the brand new and very user-friendly axial rolling head EVOline. The next development step follows already: The coolant-operated closing device that shifts the entire process time required for closing the rolling head to the ancillary time of the machine (image 2).

The closing operation by means of coolant (or compressed air) with a working pressure between 8 and 16 bar can be integrated into the machine program with a simple function. Easy, safe and fast.

Highest copy milling quality

The requirements with regard to finishing in die and mold manufacturing are process reliability, good surface quality and an extended tool life at high cutting speeds. The new copy milling cutter HSCline SuperFinish2 by LMT Fette (image 3) sets new standards in exactly these areas, especially in the finishing of hardened steel between 56 – 65 HRC . Due to its high-precision cutting edge geometry with an optimized cutting edge preparation, significant tool life improvements can also be realized. The tools featuring a multilayer PVD high-performance coating ensure a maximum of process reliability. However, if the focus is not only on a long service life but also on higher speed, the processing time can also be reduced without much effort by applying the strategy for reduced processing time. These new tools have two cutting blades and are available in a short and long version for diameters of 4 – 12 mm. The precise radius tolerance of the cutting blade is in the range of +/- 5 µm.

Highest machining volume with small indexable inserts

The difference to high-speed cutting (HSC), which exhibits an excellent surface quality, particularly in finish machining, is that in high feed-rate cutting the focus is on a short processing time during roughing. A brand new addition is the MultiEdge 2Feed mini by LMT Fette (image 4). The new insert milling cutter is used for roughing small and medium components. The positive high feed geometry of the small cutting inserts permits a maximum material removal rate even in weaker machining centers. But when this tool runs at full throttle, feed rates of 14 m/min are not unusual, for instance, for the machining of tool steel with a tensile strength of 1000 N/mm2. And the cutter has 9 cutting edges on a tool diameter of 80 mm. The cutting inserts are now also available with a theoretical corner radius of 2 mm and the carrier bodies as a face cutter and a screw-on milling cutter.

The new milling strategy significantly reduces manufacturing costs

Trochoidal milling requires rethinking of milling and opens up new performance dimensions. The result is higher removal rates at lower cutting forces. This also facilitates the optimized machining of hardened and high-strength material with reduced machining times. LMT Tools follows this strategy and for example reduced the machining time by 70% compared to conventional milling strategies while at the same time tripling service life with the VHM milling cutter DHC HARDLINE (image 5). During trochoidal milling, the feed motion of the tool is not linear but curved. This causes the wrap angle, chip load and radial depth of the cut to change constantly. In contrast to conventional milling, the mean chip thickness hm remains constant. The prerequisite, however, is a powerful CAM software and a dynamic and fast machine control.

The specialist for threading stainless steels

The new INOX tap by LMT Fette was developed especially for machining stainless steels (image 6). These difficult materials do not pose a problem. The positive torsion characteristics of the HSS-E cutting material, its special geometry and the low-friction, multilayer sliding layer based on TiAlN and WC/C ensure maximum process reliability with excellent chip flow and minimal lubrication. This also sums up the main benefit for the user: It’s reliable and reproducible application guarantees high profitability. In order to improve the quality and process reliability, pre-drilling with the X-Speed INOX drill system is recommended. The new INOX tap is available in the versions Markant for through-hole threads and Rasant for blind-hole threads in metric, metric fine, UNC, and UNF sizes.

The new and user-friendly tap catalog shows the outstanding variety of tools for threading and drilling offered by LMT Tools. At the heart of the new catalog is the LMT Guide, which guides the user to the ideal tap in four easy steps.

For many CNC applications, thread rolling, is the best choice for creating higher quality external threads in a single pass, Chipless operation.

Thread rolling technology has been resorted to on multi spindle machines, engine lathes, dedicated rolling machines for decades. However, rolling threads on machines that are not dedicated to a single part / operation is a relatively new and unfamiliar concept. It offers particular advantages on NC and CNC machines as it eliminates the costly multiple passes required in single point threading. Producing the thread in only one pass can reduce threading time by as much as 90%!

Today’s CNC machines are very versatile and can be changed over quickly to help meet demands for JIT manufacturing. A more striking benefit of CNC machines is its ability to produce higher quality parts more quickly and efficiently. Tool changes are faster and adjustments can be made without stopping the machine.

Like the CNC, single point threading is also very versatile. Most of today’s single point threading is performed by indexable insert tools as part of a very rapid CNC process. A typical part that requires a thread is routinely accommodated through fixed cycles of numerical control and a variety of other machine mechanisms. This can be a very economical method of producing smaller quantities of parts.

However, when parts are produced in larger quantities, single point threading’s versatility is less beneficial. This is because, in order to maximize effective tool life, single point inserts are processed with a limited depth of cut with multiple passes needed to cut to the thread’s full depth. The time needed to take these multiple passes can create a bottleneck. Additional passes may also be taken to deburr the thread, requiring more machine tool time or a secondary operation outside the machine. Although CNC is bringing down the total threading cycle times by making non cutting functions more efficient, these time savings are negated by the added time it takes to single point the thread. Thread rolling on the other hand, produces threads in one pass, reducing expensive CNC machining time. In addition, when a thread must be rolled, the use of a thread rolling head – attachment on CNC equipment can complete the workpiece in one single set up thereby eliminating a secondary operation on a separate thread rolling machine.

Chipless Cold Forming
Technical Advantage

In addition to doing more work on one machine in less time, thread rolling has many technical advantages over single point threading. Instead of cutting or shearing the material as is the case of single point threading, thread rolling cold forms the profile to be produced. In this process, the component material is stressed beyond its yield point, being deformed plastically, and thus permanently. A hardened die made from tool steel or HSS displaces the material along the contours of the thread profile, plastically deforming the material into the final form. The workpiece material is stressed beyond its yield point, which causes it to flow and conform to the mirror image of the die’s profile – refer to figure 1.

• Stronger Threads

The grain lines of the rolled material aren’t interrupted like those of cut material: they are compressed and moved more perpendicular to the centerline of the part, increasing the thread’s tensile strength by 10% to 30% over cut threads. This aids in resisting tensile forces acting against a thread, which pulls along the centerline of the part. Parts that can benefit from this increase in tensile strength include cylinders, piston rods, tie rods etc.

• Burnished Thread Flanks

The compression of the material during the rolling operation causes workhardening at the thread’s surface. This is most apparent in the thread’s root and along its flanks, making them more wear resistant. The compression of material to the die’s form provides a very exact profile with a surface finish better than grinding can achieve. Shearing a material produces a rough surface finish, but, compressing it produces a smoother and harder surface finish, resulting in greater resistance to wear, corrosion and galling. This improved resistance to wear is a particular benefit for Valve stems and other parts that are susceptible to harsh, corrosive atmospheres. Nuts that must travel freely over long distances in contaminated atmospheres also benefit from the smooth surface finish.

• Improved Wear Resistance

A rolled thread also has up to 70% increased fatigue resistance over a cut thread. Since rolling is a chipless operation, the profile is free from burrs, tear marks, chattering marks, and sharp exit points, all of which are focal points for stress. The smooth, burnished surface of a rolled thread has fewer hills or valleys where stress can build up and cause the part to fail from fatigue. This characterestic is most beneficial at the thread run out , or distance of unusable or incomplete thread. If a part were to fail from fatigue, it would fail here at the end of the thread, where the entire load is concentrated. Parts that are under constant load greatly benefit from thread rolling because the threads have a smooth work hardened, radiused and burnished runout.

• Profile Accuracy

With thread rolling, thread quality is more consistent from part to part than with single point threading. Even with the best grind possible, a single point threading insert will start to wear the moment it touches metal. The longer the thread to be cut, the greater the potential for deflection and chatter, resulting in shorter tool life. However, the dimensions of thread rolling dies do change with use. Every time the die rolls, they gain stress. The stress builds up to a point where the hardened material of the die just fatigues and breaks away in small pieces at the crest where the die is doing the most work. Upto this point, the dies will make the same profile every time. Practically no adjustments are needed throughout the life of the rolls, which is typically tens of thousands of parts per set.

Economic Advantage

• Material savings

Since thread tolling displaces material rather than removing it, smaller stock can be used to produce a given thread diameter than must be used with single – point threading. Whereas single point threading is a reductive process, thread rolling actually increases the part’s diameter to the thread’s outer diameter. Therefore, the thread rolling diameter of the blank is not as in single point thread cutting, where it is identical with the outside (major) diameter of the thread, but , is the pitch diameter of the thread. With many workpieces, this means a considerable saving on material, especially if the material has been drawn to the pitch thread diameter when it can be used immediately. In addition, thread rolling may negate many of the chip problems associated with materials such as SS 304, Inconel and titanium.

• Extremely short machining time

Rolling speeds ranging from 20~90 m/min are considerably higher than the cutting speeds used in Thread cutting operations. When cutting with thread chasing heads, speeds rarely exceed 10 m/min. Thus when using the thread rolling processes, the net thread rolling time will never be the deciding factor.

For e.g.:

Threading a M 16 , 19mm on a cast steel journal, the time to thread cut was 4.8 secs per piece. However, when rolling was performed, only 0.8 secs were required with an axial type rolling head and 0.2 secs with a radial type head.

• Longer Tool Life

For any thread rolling process performed with LMT FETTE attachments and rolls, the long tool life of the thread rolls gives extremely low tool costs. Refer to the table below for an example:

• Full utilisation of the machine

The well designed LMT FETTE thread rolling heads are compact units needing a rotary motion in order to function properly. To meet that requirement, simple turning lathes will suffice. But, these rolling heads can also be used on Turret lathes, automatic lathes and CNC Lathes, giving thread production without problems on any workpiece, able to accommodated in the machine, in a short part of the total cycle time.

Thread Forms

Thread rolling is applicable to many standard and special thread forms. Besides common 60° profiles, other types of threads that can be rolled include Parallel and tapered “V” Type threads, Acme, Knuckle, and in some cases Buttress. However, it should be noted that as long as the Flank angle is not less than 10 ° practically any special shaped thread can be rolled between 1.4mm and approximately 230mm. In addition, depending on the specific application, it may be possible to reduce tube diameters, swage the ends of tubes, roll annular ring profiles, mark logos, letters and numbers.

Work Piece Material

Within certain given physical parameters, practically any work piece material can be thread – rolled, including structural steels, case hardened steels, stainless steels, heat treatable steels, Aluminum, and nickel based alloys such as Inconel 718.

The three main physical parameters that determine whether rolling is feasible are

• Elongation factor

As the material will be plastically deformed by pressure, it should have a minimum elongation factor of 5% to 7%. Cast Iron, pure bronze, hard brass alloys and other hardened materials that have less than 5% elongation are too brittle to be thread rolled.

• Hardness & Tensile strength

As a general rule Hardness should not exceed R_c 40, and the material Tensile strength should not exceed 1700 N/mm².

Chemical composition also can be a factor. The work piece material should not contain more than 1% lead additives for free machining. In addition, the type of profile and the amount of displacement have a direct impact on the material’s ability to be rolled.

The work piece material to be rolled may affect the choice of thread – rolling head / attachment, surface treatment on the thread roll, and thread – rolling system. There are three main systems:

Axial, Tangential and Radial.

Axial

The axial system comes from the front end of the part along the centerline – refer to figure 6. While thread lengths produced by the other two systems are limited to the width of the rolls, the axial system is designed to produce unlimited thread lengths. The thread form on the axial rolls consists of straight annular rings that are ground to the pitch of the thread to be produced. The rolls are positioned in the head at a skew angle that is approximate to the thread’s helical angle, producing a forward motion ; hence, the threads are self – feeding.

If the first ring on the axial roll were full profile, it would do all the work. Therefore, similar to a chamfer on a tap, a progression or lead is required to help the rolls start and to provide better tool life. By having more progressive rings on the rolls, tool life can be optimised on longer profile lengths.

A shorter progression can be used to allow threading up closer to a shoulder, but the rolls wont have a long tool life. The closest that the axial system can thread to a shoulder is approximately 1.5 times pitch. Where, it is desirable to thread very close to the shoulder, a Tangential or Radial thread – rolling system will do a better job.

Although the axial system cant thread as close to a shoulder as the other two systems, it has the unique advantage of threading larger diameter stock. Since the axial rolls only produce one thread at a time, the heads are simpler in design. This leads to a greater diameter capacity. Currently, the FETTE axial systems can roll profiles upto 230 mm in diameter.

Tangential

The tangential system uses one roll above and one below the work piece. The rolls are fed from the side ( X – axis), pressing deeper with each revolution of the work piece. When the centerline of the rolls in line with the centerline of the work piece, usually between 15 to 30 revolutions, the forming process is completed – refer figure 7. Neither the work piece nor the rolls move axially. Therefore the length of the thread that is formed depends on the width of the roll. Therefore the length of the thread that is formed is dependent on the width of the roll.

The tangential systems use helical profiled rolls that are mounted on straight stationary spindles. The thread helix angle to be produced is ground onto the roll ; in other words, it is a mirror image of the thread. Therefore it is just a matter of using left hand rolls to produce left hand profiles and right hand rolls to produce a right hand profile. However, the same attachment can be used with either type of roll.

The rolls are chamfered at both ends to provide a base of support for better roll life. The length of the chamfer is equal to the thread runout, or distance of unusable or incomplete thread to a shoulder, which is approximately ½ to 1 times the pitch. Therefore, it is possible to thread very close to a shoulder.

Tangential systems can be conveniently mounted on the cross slide of screw machines, automatic lathes and CNC lathes.

Cycle Times

All systems produce the thread in ONE pass, thereby eliminating the costly multiple passes required in single point threading and reducing threading time by as much as 90%.

Since the axial system is the only one that produces one thread at a time, its threading cycle time will be dependent on the length of the thread. For eg: Lets calculate the cycle time for a thread that is M 20 x 1.5, length of 40 mm long. The rolling time in an axial system would be:

The savings in machining time that thread rolling can provide over single point threading can be enough to justify the investment in a thread rolling system.

Tooling costs, Machine time and Parts per shift

Considering the fact that the cycle times are so low for thread rolling , it would translate into savings of machine time and optimum machine utilisation . Further, a shop can reduce cutting tool costs and decrease downtime if it rolls threads rather than cuts them. The roll life for most applications are relatively high, thereby ensuring reduced downtime. By implementing thread rolling, the parts per shift will dramatically increase when compared to thread cutting.

Machine Options 

Since it produces threads in one pass, thread rolling requires more horsepower than single point threading. However, the power requirements for thread rolling typically are less than the capacity of modern machine tools.

Thread rolling creates a tremendous amount of heat very quickly. Since the surface of the thread is constantly changing during the forming operation, this heat is dissipated very easily into air moving around the rotating workpiece or thread rolling head/ attachment – hence the term “Cold Forming”. Using a water soluble coolant also dissipates heat and helps extend the life of the roll.

FETTE Thread rolling heads/ attachments can be used on almost any type of machine tool, including CNC automatic lathes, basic engine lathes, rotary transfer machines, and machining centers.

As long as the head / attachment and the workpiece can be positioned properly, the thread rolling process can be employed virtually without any restriction. However, because today’s CNC machines are designed as smaller, more compact units, thread rolling head / attachment clearance may be a factor which needs to be looked into during the selection process.

Initial Cost

 To potential customers, the initial cost of a thread rolling system may seem like a significant stumbling block. Initial costs for single point thread rolling systems are minimal compared to those for thread rolling systems.

While the initial costs of all three types of thread rolling systems are higher than single point threading systems, the long – term costs are lower due to longer tool life and substantially shorter machining times. Although initial cost savings may be a more tangible benefit, customers must consider the techincal and economic advantages offered by thread rolling in the long term.

Courtesy: LMT India Pvt Ltd