Big Gears Better and Faster CARBIDE INSERT CUTTING TOOLS PROVIDE INCREASED PRODUCTIVITY and QUALITY

Demand for indexable carbide insert cutting tools has grown over recent years, due in large part to the increased production requirements for wind turbine and other large-module gearing. Shown here is an indexable carbide insert hob from Seco Tools Inc. Big Gears Better and Faster CARBIDE INSERT CUTTING TOOLS PROVIDE INCREASED PRODUCTIVITY AND QUALITY

William R. Stott, Managing Editor

Indexable carbide insert cutting 1979. LMT-Fette began making these due to increased production require- tools for gear manufacturing are noth- tools in the mid-1980s. ments in mining and other energy sec- ing new. Ingersoll first introduced But big gears have recently become tors. The result is that there’s been a indexable carbide insert gashing tools a very big business, thanks in part to renewed interest in carbide insert cut- in 1977, and carbide insert hobs in the wind turbine industry, but also continued

www.geartechnology.com January/February 2011 GEARTECHNOLOGY 37 a

Multi-start hobs are one of the more recent innovations in indexable carbide insert gear tooling, as shown in these tools from a) LMT-Fette and b) Ingersoll Cutting Tools.

38 GEARTECHNOLOGY January/February 2011 www.geartechnology.com Indexable carbide insert hobs are most commonly assembled from individual segments, as shown in this exploded drawing of an Ingersoll hob. ting tools, and a host of new suppliers have entered the market—especially the U.S. market—over the past few years. “The manufacturers of large- module gears used in wind energy are focusing to increase their production efficiency by higher cutting speeds and feed rates,” says Dr.-Ing. Friedrich Momper, manager of gear products at LMT-Fette. Those higher feeds and speeds require carbide tools rather than the traditional high speed steel, Momper says. Darryl Witte, vice president of sales at Banyan Global Technologies, agrees. Banyan manufactures a line of carbide insert milling cutters, gear gashers and shapers. “Wind growth has for the first time allowed for higher volume manufacturing of coarse-pitch, or large-module, gears. In that higher production mode, indexable carbide Internal gear gashing is one of the primary uses for indexable carbide insert solutions are paramount to improve gear cutting tools. Shown here is an Opti-Cut gear gasher from Gleason Cutting Tools. cost metrics in production of these geared components.” “We have seen a considerable increase in the demand for these tools in finishing and pre-grind applications, for both the indexable gashing tools and indexable hobs and shaper cutters,” says Michael Tennutti, senior product manager at Gleason Cutting Tools, which sells indexable tools under the Opti-Cut brand name. “A major driv- er has been the global energy market, including applications for mining and heavy construction equipment, but Different manufacturers offer different approaches to optimizing the technology. especially for wind turbine gearboxes.” For example, milling cutters from Safety (left) use a wedge-style clamping system to Why Carbide Inserts? enable greater tooling flexibility. Banyan also uses wedge-style clamps on some of The main advantage of indexable its finishing cutters (right). continued

www.geartechnology.com January/February 2011 GEARTECHNOLOGY 39 carbide insert tooling is that it allows well beyond the size range possible in vide cutting speeds 4–8 times faster manufacturers of big gears to increase solid carbide.” than HSS tools. This means you can their feeds and speeds without having Some manufacturers of these tools produce more parts in less amount of to go to a solid carbide tool. In fact, offer them in module ranges up to 40, time.” beyond a certain size range, solid car- 50 or more. “In our experience, especially with bide tools aren’t practical or even pos- Because the only alternative to large gears, we have found it is not sible to manufacture. these carbide insert tools is high speed uncommon to see 50–75 percent reduc- “Costs aside, some coarse-pitch steel (HSS) tools, there is often a dra- tion in cycle times compared to HSS,” modules simply cannot be produced in matic difference in productivity when says Frank Berardi, gear machining solid carbide, necessitating an insert- comparing the options. product manager for Ingersoll Cutting ed blade approach” says Gleason’s “The main advantage over HSS Tools. Tennutti. “Larger modules such as 20 is increased productivity,” says Todd Another advantage is that carbide module can now be made in diameters Miller, milling tools product manag- tools can often be run without coolant, ranging from 350 to 400 mm, which is er for Seco Tools. “Carbide can pro- which provides additional environmen- tal benefits and cost savings. But even in module ranges where solid carbide is available, indexable we work here

Gear milling tools are generally optimized per application, with different inserts for profile and root, as shown in this milling cutter from Seco Tools.

Clifford-Jacobs custom high-strength forgings work everywhere and for some of the biggest names in mining, aerospace, and energy. So whether you need a 5-pound gear blank or an 800-pound finish machined component, depend on Clifford-Jacobs’ uncompromising quality. It comes with fast estimates, ready resources, part warehousing, and zero tolerance for failure.

SINCE 1919 SINCE 1919 Indexable carbide insert shaper cutters are offered by a number of manu- [email protected] | Clifford-Jacobs.com | 888.352.5172 | ISO 9001:2000 facturers, including Ingersoll (right), Banyan (left) and Gleason.

40 GEARTECHNOLOGY January/February 2011 www.geartechnology.com insert tools can offer some advantages. the old coating and depositing the new “Changes in part material and hard- “Solid carbide tools are very expen- coating) is not handled properly, this ness can be accommodated by simply sive tools to keep on hand,” Miller will lead to loss in an effective utili- changing insert grade or edge prep,” says. “Typically you need three to four zation of a solid type hob. With the says Ingersoll’s Berardi. “Likewise, of the same tools per job. One in ser- inserts, inspected by the supplier, the slight modifications in tooth involute vice, one on the shelf ready to go on customer gets a ready-to-start solution form can often be accommodated by the machine and one to two getting with repeatable accuracy and tool life.” insert or pocket modifications.” re-ground and re-coated. Refurbishing Another benefit of the inserted Drawbacks is typically done by an outside vendor, blade tools is the flexibility allowed by Taking advantage of carbide tools which takes time. Indexable carbide changing out the inserts. This flexibil- requires the ability to run at higher inserts are much less expensive and ity can allow different parts to be cut speeds and feeds, as well as machin- help reduce costly inventories.” with the same cutter body simply by ery that is extremely rigid. Because of LMT-Fette’s Momper agrees. changing the inserts. continued “Using indexable type cutting tools overcomes the issue of reconditioning of solid type hobs,” Momper says. “If reconditioning (grinding, stripping

www.geartechnology.com January/February 2011 GEARTECHNOLOGY 41 these requirements, you can’t just put with carbide in mind: “Today’s CNC application, as well as new entrants one of these tools on an old gear gasher hobbers and shaping machines offer into the marketplace. and expect it to perform. improved stiffness characteristics and One of the newest competitors in “Realistically, the limiting factor increased power ratings, and can take this field is Sandvik, whose CoroMill in using this technology to its fullest advantage of today’s cutting tool mate- 170 series of milling cutters was extent has been the available machine rials and coatings. The user can run introduced at IMTS 2010. Sandvik tools,” says Brian Nowicki, vice presi- at much higher speeds and feeds than has developed this tool specifical- dent of sales & marketing for Cimtek with high speed steel tools.” ly with the wind turbine industry in LLC, which represents Safety Cutting Recent Developments mind, concentrating on module rang- Tools. Despite the fact that indexable es from 12–22, according to Kenneth Gleason’s Tennutti agrees that carbide insert tools have been around Accavallo, gear industry applications these tools require modern, rigid for a long time, there continue to be specialist. machines that have been designed improvements in their design and Even though they are a relative newcomer, Sandvik is focused on developing its tools for more and more applications, Accavallo says, and they have also been working hard to develop indexable carbide insert hobs, which the company expects to fully introduce to the market in 2011. But even at the more established companies in the market, R&D con- tinues with an emphasis on increased quality and productivity. “Recent emphasis has been in development of carbide milling grade substrates, coatings and post coat pro- cessing to increase tool life,” says Ingersoll’s Berardi. “In addition to grade development, advanced pressing technology has allowed us to develop freer cutting positive geometry inserts in precision tolerances.” Berardi points to Ingersoll’s S-Max double positive insert as an example of the latest in insert technology. “Originally developed for our Max-line milling cutters, it has proven to be an effective and economical performer for rough gear gashing. Improved manufacturing techniques in production of cutter bodies, especially insert pocket- ing, allows us to now produce finish gear cutters to very tight tolerances without the use of shims or adjustment mechanisms. For the customer, this greatly simplifies cutter set-up and tool change. We are applying this same technology for pre-grind and final finish applications, and we can now provide precision pressed and ground con- cave and convex inserts to cover the entire involute form.” According to Berardi, one of the advantages of Ingersoll’s “freer cutting geometries” is that they reduce power consumption on the machine, especially for rough cutting. “This allows us to perform the same cut at higher operat-

42 GEARTECHNOLOGY January/February 2011 www.geartechnology.com ing parameters with little or no increase undergone significant development, nal to external gears, Nowicki says. in horsepower consumption, compared says Cimtek’s Nowicki. Instead of the Banyan, Gleason and Ingersoll with HSS and solid carbide,” Berardi traditional tangential screw mount used offer indexable insert shaper cutters, says. “In addition, the double-positve by many manufacturers of gashing but these are also areas where the man- S-Max provides smoother cutting on tools, Safety employs what Nowicki ufacturers are working to improve the the tooth flank, which greatly reduces describes as a “wedge-style clamp.” tools. axial forces. This has opened up oppor- The wedge provides increased flex- “For internal gears, we have a new tunities for customers who have older ibility for the tool, because it allows finish gasher with interchangeable equipment, or lower HP machines, to quick and easy changing of the inserts hardware that is adaptable for negative still take advantage of the benefits of to accommodate a wide range of pitch/ or positive inserts with four cutting indexable tooling.” diameter combinations and surface fin- edges,” says Ingersoll’s Berardi. “The Improvements in the tools have ishes. A change in inserts is likewise insert pocket is designed to allow the resulted in improvements in the part all that’s needed to switch from inter- same tool body to cover a range of quality. continued “As we continue to improve finishing capabilities, we are seeing more applications for machining teeth to pre-grind and final finish dimensions,” Berardi says. “For many applications, we can achieve the profile and finish tolerance by finish milling or finish hobbing, thus eliminating the need for grinding.” Eliminating the grinding process is also on the minds of engineers at LMT- Fette and Seco. “With the new gashing cutters and ICI hobs, you can achieve high gear qualities,” says LMT-Fette’s Momper. “In some cases, grinding processes could be minimized or even become redundant.” “We are now able to achieve gear tolerances of DIN 10 or better, depend- ing on module size, with an indexable OOURUR AABILITIESBILITIES -- YYOUROUR AANSWERSNSWERS carbide tool,” says Seco’s Todd Miller. ROBUSTROBUST PRODUCTSPRODUCTS BUILTBUILT TOTO LASTLAST “Whenever you can get to a point of CQ GEARBOX (Chongqing Gearbox & Machinery Co., Ltd.) eliminating grinding, there are tremen- With over 40 years of proven experience in building the world’s most rugged products, CQ-GEARBOX is a leader in the transmission technologies sector. Our distinquished expertise efficiently fuses engineering, design, & manufacturing dous cost savings available. Grinding with analytical prowess, Let CQ-GEARBOX solution based products transform your company through all of machines are very expensive, and the manufacturing’s toughest challenges. grinding operation is typically much www.chongchi.com/en/www.chongchi.com/en/ -- www.fepti.comwww.fepti.com more expensive than milling with car- FEPTI: The American offices of CQ Gearbox Co., Ltd. CQ-GEARBOX, CSIC, FEPTI. ALL RIGHTS RESERVED 350 Church Street, Windsor, Ontario, Canada N9A 7C8 bide tools.” Tel: 519-817-8761 - Fax: 519-256-6888 - [email protected] - [email protected] Another recent development in indexable carbide insert hobs is the You’re two-start hob. Ingersoll, Kennametal You’re and LMT-Fette all offer this option. oneone callcall awayaway fromfrom “This year we introduced a new two-start ICI hob, which can nearly thethe rightright decision!decision! double productivity for machining gears with large numbers of teeth,” says Ingersoll’s Berardi. “This is LARGE LOOSE GEARS, MUD PUMPS, YAW & PITCH DRIVES, SPEED-UP, ROLLER MILL, MARINE, REVERSE CLUTCHING & VERTICAL MILL GEARBOXES a segmented design with the same design features as our single-start hob. Although it’s primarily designed for roughing and semi-finishing, for many applications we can achieve finish quality.” At Safety, the gashing tool has also

www.geartechnology.com January/February 2011 GEARTECHNOLOGY 43 gear diameters of the same module, by ule gears,” says Ingersoll’s Berardi. “I times,” says Cimtek’s Nowicki. changing inserts.” believe we will see some breakthrough Conclusion “Another area of great inter- in this area in the near future.” Even though these tools have been est is our development of indexable Kennametal produces inserted around for a long time, in one form insert roughing shapers,” Berardi blade hobs as small as 4.5 module, or another, there has clearly been a says. “We’ve had great success with according to Klaus Wichmann, man- resurgence in the marketplace, both in this product, and we are working on ager of gear milling for Kennametal the demand for the tools and the num- expanding the offering to cover a wider GmbH in Germany. But Wichmann ber of suppliers who make them. Also, range of sizes. Shapers are still wide- believes modules as small as 3 are pos- there has been significant research and ly used for double-helical gears and sible. development on the tools, meaning shoulder applications where there is Banyan is also aiming for smaller that they provide greater productivity, no clearance for gashing or hobbing gears. “We continue to push to smaller higher quality, and more manufactur- cutters. It is typically a very time-con- pitch sizes, not only for gear, spline and ing options than ever before. suming process. With the indexable rack milling, but also for finer pitch hob- So manufacturers of large-module roughers we can remove the majority bing, so as to reduce the costs associ- gears who haven’t yet investigated of stock, leaving 0.2 mm or less for the ated with what is commonly viewed as these tools might want to reconsider. finish shaper. This typically results in one of—if not the—most expensive tools The range of suitable applications for 50–70 percent reduction in machining used in gear manufacturing,” says Witte. indexable carbide insert gear cutting time.” Another area that will continue to tools has grown considerably, and it The Future improve is the customization of the appears that it will continue to grow for A number of manufacturers are inserts and insert configuration to the foreseeable future. working to increase the size range of achieve specific goals. See pages 46-49 for complete con- gears for which indexable tools are an And, of course, the manufactur- tact information on the companies appropriate option. In particular, small- ers will also continue to work on bet- mentioned in this article. er gears seem to be one of the next ter insert materials and coatings. targets. “Continued advances in substrate, “We are constantly working on geometry and PVD coating technology ways to cover a wider range of gear will continue to improve cutting speeds, tooth sizes, especially in smaller mod- metal removal rates and ultimately cycle

44 GEARTECHNOLOGY January/February 2011 www.geartechnology.com www.geartechnology.com January/February 2011 GEARTECHNOLOGY 45 Carbide Insert Cutting Tools—The Suppliers Below are profiles of the major companies who are suppliers of carbide insert cutting tools for gears. The cutting tool ranges are described, and any specialties or unique capabilities are noted.

Banyan Global Cimtek LLC Gleason Technologies Corporation “Gleason has considerable knowl- edge and experience in gear manufacturing, and we have invested significant R&D in the analytical development of the tool tooth profile,” says Michael Tennutti, senior product manager for Gleason Cutting Tools. “This allows us to optimize the finishing stock for pre-finish tools, and to improve the final gear accuracy for “Safety’s biggest advantages lie in finishing tools.” multiple areas,” says Brian Nowicki, vice president of sales & marketing for Cimtek. “First is Safety’s experience. Safety was one of the innovators of gear gashing and has been selling gear “Our tools are sold as a custom gashing tools in Europe for more than solution for every application,” says 30 years. Darryl Witte, vice president of sales. “Second, Safety uses a “wedge- “We evaluate the machine tool, fixtur- style” clamp versus the traditional ing and part condition to tailor-fit a tangential screw mount. This unique tool to the process. Customers have the design allows Safety gashers to cut a freedom to purchase the cheapest tool wide range of pitch/diameter combi- possible, the most cost effective, or the nations with a single cutter, simply one that will return the highest quality by changing inserts and/or wedges,” part; every one of which will return a Nowicki says. different design with a different cost.” In addition, the unique wedge “We at Banyan use our years of design allows the gashers to machine metalworking experience to design both internal and external gears with optimal indexable carbide solutions for the same cutter body, or to rough both coarse and fine pitch gear cut- machine and finish machine with the ting.” same cutter body, simply by changing inserts, Nowicki says. Solutions offered: Rough and fin- “We have also been able to opti- ish gashing cutters for internal or exter- Solutions offered: Milling and mize the combination of rake face nal application from 1–50 module, 1" gashing cutters from module 5–45. configuration, edge preparation defini- to 36" diameters. Spline milling tools tion and coating type and thickness for any size. Indexable shaper cutters for For more information: maximum performance of our Opti-Cut roughing, 2–25 module, indexable hobs Cimtek LLC inserted carbide tools. These character- from 2–45 module. Brian Nowicki, vice president of istics are all specifically developed for sales & marketing each individual application.” For more information: Phone: (847) 628-9942 Banyan Global Technologies [email protected] Solutions offered: Carbide insert Darryl Witte, VP Sales www.cimtekllc.com tools for ID or OD gashing (both 20836 Hall Rd., Suite 156 Clinton Township, MI 48038 roughing and finishing tools), gear Phone: (815) 786-5986 shaping and gear hobbing. Carbide [email protected] insert hobs are available for diameters www.banyangt.com greater than 125 mm.

46 GEARTECHNOLOGY January/February 2011 www.geartechnology.com For more information: ishing gashers with through-tool cool- Gleason Cutting Tools Corp. ant channels, carbide insert hobs for 1351 Windsor Parkway modules 6 and up, including multi-start A Loves Park, IL 61111 USA hobs and shapers in modules 6–12. Phone: (815) 877-8900 Better Way [email protected] For more information: The “NDG” Method www.gleason.com Ingersoll Cutting Tools (patented) Frank Berardi, product manager gear machining 845 S. Lyford Road New Power Rockford, IL 661108-2749 for your Ingersoll Phone: (815) 387-6600 [email protected] Gear Measuring Cutting Tools www.ingersoll-imc.com & Inspection Systems Kennametal TTi - 300E

“Kennametal is a pioneer in using positive geometries on the inserts and innovative positioning of the inserts in the body,” says Klaus Wichmann, manager of gear milling for Kennametal Technologies GmbH in Germany. “This leads to a very effec- “All of our gashing and hobbing tive and smooth cut. Further, this inno- TTi - 2000N cutters feature the angled insert screw vative design helps to reduce the power hole, which Ingersoll introduced to the machine needs to run the cutter. provide more secure clamping and eas- This saves the machine from wear as ier access for indexing inserts—espe- well as the cutter itself.” cially in hob assemblies,” says Frank Berardi, product manager for gear machining at Ingersoll Cutting Tools. “It has the added benefit of error-proof- ing insert orientation.” • Fast & Accurate gear “The unique segmented design of measurement from a small Ingersoll hobs provides an expandable gear up to a super large gear assembly, and simplifies repair. The • User Friendly spiral segments are manufactured in one setup, ensuring the highest precision possible. Because of this, segments can be ordered separately for replacement or expansion of the assem- “Kennametal has invested a huge bly. This can be done by the custom- amount of money to increase the man- er, as there are no fitting operations ufacturing quality, especially of the involved.” tool bodies. We are using a unique USA Office Tokyo Technical Instruments USA Inc. “Perhaps the greatest advantage we and state-of-the-art closed-loop sys- 297 Kinderkanack Rd., #133 offer is the 30-plus years of experi- tem between the production machine Oradell, NJ 07649 ence in designing indexable gear cut- and our measuring and quality station. Ph: 201-634-1700 ting tools. These are highly engineered This brings us 1-2 better quality classes Fax: 201-262-2187 products, and most often each applica- compared to the standard methods.” Tokyo Headquarters tion requires a unique solution.” Tokyo Technical Instruments Inc. Solutions offered: Carbide insert Main Office Ph: +81-3-3726-4188 Solutions offered: ID and OD gashers (for both internal and external Factory Ph: +81-284-73-1733 roughing gashers for modules 6 and gears) from module 6–40, finishing See Details up, ID and OD finishing gashers for gashers (for both internal and external www.tti-geartec.jp modules 6 and up, roughing and fin- continued

www.geartechnology.com January/February 2011 GEARTECHNOLOGY 47 48 GEARTECHNOLOGY January/February 2011 www.geartechnology.com gears) from module 3–30, hobs, includ- For more information: For more information: ing multiple-start hobs, from modules LMT Tool Systems GmbH Sandvik Coromant Company 6–40, as well as other specialized tools. Grabauer Str. 24 1702 Nevins Road D-21493 Schwarzenbeck Fair Lawn, NJ 07410 For more information: Germany Phone: (800) SANDVIK Kennametal Inc. Phone: +(49) 41-511-2311 www.sandvik.coromant.com/us 1600 Technology Way www.lmt-tools.com Latrobe, PA 15650 Phone: (724) 539-5000 www.kennametal.com

Seco Tools Sandvik Coromant

A relative newcomer to the carbide insert gear cutting industry, Sandvik Coromant has targeted module ranges that are most commonly used in the wind turbine industry, says Kenneth Accavallo, gear industry applications specialist. Sandvik’s first entry into the gear tool market is its Coromill 170 series “Seco has worked hard developing of milling cutters, designed for rough- innovative coatings and carbide grades ing gears in modules 12–22. Although with superior performance,” says Todd Sandvik’s range is more limited than Miller, milling tools product manager. other manufacturers, they are also “Today, Seco is a leader in coating developing additional products for gear technologies with the development of manufacturing, including indexable our DurAtomic coating. We also have carbide insert hobs, expected to be for- an extensive engineering background mally launched in 2011. with the design and development of LMT-Fette milling cutters and tool holders. We Solutions offered: Carbide insert have brought all the same technology According to Dr.-Ing. Friedrich milling cutters in modules 12–22, with into the development of our gear mill- Momper, manager of gear products, carbide insert hobs to be launched in ing cutting tools and are continuously LMT-Fette offers: 2011. • A wide range of gear gashers improving.” and indexable carbide insert hobs Solutions offered: Carbide insert • Customized tools to the specifi roughing and finishing tools with mod- cation of customer profiles ules from 1–50, carbide insert hobs • State-of-the-art carbide grades with modules from 6–26. and coatings, as well as insert geometries tailored for gear cut- For more information: Seco Tools Inc. ting processes 2805 Bellingham Drive • Engineering and application Troy, MI 48085 know-how for both solid-type Phone: (248) 528-5200 hobs as well as indexable type [email protected] gear cutters www.secotools.com

Solutions offered: Single-start carbide insert gear hobs from modules 5–40, double-start gear hobs, gear roughing cutters with or without internal cooling from modules 6–36, gear finishing cutters with or without internal cooling from modules 8–24.

www.geartechnology.com January/February 2011 GEARTECHNOLOGY 49 Faster Gashing in Finland

For nearly 50 approximately years, Takoma 2.5 meters (8.2 Gears (Parkano, feet) in diameter. Finland) has spe- The part was cialized in pro- machined from viding large- 34CrMo4 steel. scale gears and T a k o m a g e a r c o m p o - had previous- nents to custom- ly used a 230 ers, mainly in its mm (9.06 inch) domestic mar- HSS hob to cut ket. Concentrated teeth on the ring heavily in the gear. Running marine indus - at a speed of try, the company 25 meters/min prides itself on (82 feet/min) minimizing lead and feed rate of times and costs 0 . 1 2 m m / r e v w h i l e m e e t i n g (0.0047 inch/ extremely strict rev), the opera- quality require- tion took 1,260 ments. Dedication to maintaining these After consulting closely with minutes per component. Upon apply- standards leads the company to con- Koitto and other employees at Takoma, ing the CoroMill 170, Takoma was stantly evaluate its operations and track Sandvik Coromant engineers spent sev- able to increase cutting speed and feed developments in technology that can eral months designing and testing a rate to 126 meters/min (413 feet/min) lead to process improvement. custom tool optimized for the process. and 0.20 mm/rev (0.0079 inch/rev), Traditionally, Takoma has used The gear cutting tool that resulted from respectively. This reduced cycle time HSS hobs for the cutting of gear teeth. these efforts was brought to Takoma by nearly 60 percent, to just 510 min- In 2009, the company purchased sever- for multiple tests and runoffs and then utes per component. al new machines for the production of implemented with Sandvik Coromant’s “We are now using the CoroMill large gear components for use on ships. assistance. It achieved very similar 170 all of the time and saving a signifi- Slewing rings with an outer diameter results to the original tool, but with cant amount of time,” says Koitto. “By of approximately 2 meters (6.56 feet) a slightly reduced cost. More impor- shortening our machining time, it also are produced from 42CrMo4 steel and tantly, turnaround times for delivery allows us to reduce turnaround to our require high dimensional tolerances. were less than a week, compared to 12 customers. Instead of taking five weeks Takoma initially began machining the weeks for the old tool. This allowed to process an order and provide fin- slewing rings’ teeth with a specialized Takoma to maintain much more flex- ished parts, we can now provide cus- gear cutter that provided acceptable ibility in responding to customer tomers with the same service in four quality levels, but was expensive and needs. Additionally, while working on weeks.” required lead times of up to 12 weeks this project with Sandvik Coromant, In addition to allowing faster ser- to receive. Feeling that a better option Takoma was exposed to the CoroMill vice to their customer, productiv- must exist, the company contacted a 170, a new cutter for gear milling that ity gains from implementation of the provider of tooling used in many of the the company felt held potential for CoroMill 170 have resulted in annual secondary operations of its parts. some of its other applications. cost savings of 20,000 euros. “We have worked with representa- The CoroMill 170 was developed tives from Sandvik Coromant for over to optimize milling applications in For more information: 30 years in regards to drilling, milling large gears, module 12–22, an area tra- Takoma Gears and turning tools,” says Jyrki Koitto, ditionally covered by indexable inserts Vanhantalontie 3 production manager at Takoma Gears. and HSS tools. The tool provides 39700 Parkano “We knew that they were increasing robust performance through design Finland Phone: +(358) 20-184-7400 their focus on tooling for cutting gear focus on its shape and providing secure www.takoma.fi teeth, so we asked if they had or would insert seats. Takoma chose to apply be interested in developing a tool that a 300 mm (11.81 inch) version of the *For Sandvik, please see p.49. would perform this application for us.” tool to a marine ring gear measuring

50 GEARTECHNOLOGY January/February 2011 www.geartechnology.com