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December 2019

FVA Software and Service

FVA Software and Service’s expert team of mechanical engineers and software developers enables its customers to develop and implement individual transmission models, complex calculations, and programming tasks.

Designing and creating gears can often be a complex task involving mountains of data and mathematical equations. It can be a daunting, but necessary, endeavor that some manufacturers might struggle with from time to time. The experts of FVA Software and Service are available to ease that struggle and ensure the proper scientific methods are […]
Kenneth Carter

Reducing Tool Wear in Spiral Bevel Gear Machining with the Finite Element Method

This virtual design approach uses real-world cutting tool geometry, automatically generated gear blanks, and known process kinematics to simulate the cutting process.

Due to the complexity of spiral bevel gear machining, the cutting tools can be a significant cost of gear manufacturing. Unlike the price of the material, which is fixed by the market, the cost of tooling and subsequent re-grinding can be lowered through reducing tool wear and increasing tool life. Current methods for making these […]
Fang Hou, Yantao Zhang, Syed Wasif, Pete Mattson, Kerry Marusich

Experimental tests to predict plastic gears’ lifetime

Experimental tensile fatigue data can be used to predict plastic gear life and the polyamide-based polymer loaded with glass fibers can be used for the metal replacement of gears used in applications with high power.

One of the major problems of plastic gears is the lack of data about their lifetime. Literature doesn’t contain numerous data on this subject. Even if it reported them, the number of tests, the variables involved, and the test methods are so varied that it would be difficult to compare them with those needed. This […]
Davide Albiero, Raffaele Mazzarella

Understanding the mounting distance: Intersected-axes gearing (bevel gearing)

To favorably configure bevel gears in intersected-axes gearing, the mounting distance must be one of the most important design parameters.

Mounting distance is one of the most critical design parameters in intersected-axes gearing (in straight bevel gearing, spiral bevel gearing, and so forth). In this article, the mounting distance is discussed with focus on “geometrically-accurate gearing” (that is, with focus on “perfect” gearing). The term “geometrically-accurate gearing” means gearing with zero deviations of the actual […]
Dr. Stephen P. Radzevich Ph.D., Dr. (Eng) Sci.

November 2019

Machines Profile: Heller Machine Tools

Heller Machine Tools develops and produces state-of-the-art machine tools and entire production systems for metal-cutting processes.

Heller Machine Tools is known for two things: its machines and its engineering solutions. Heller offers a wide range of horizontal machining centers used in a plethora of industries, and it’s not just the machines that make Heller stand out. It’s also the company’s engineering department that is — in a word — awesome. “Experts […]
Kenneth Carter

Tooling Profile: Advent Tool & Manufacturing

Advent Tool & Manufacturing supplies machine shops and manufacturers across the globe with solid carbide, inserted thread mills, and custom form mills designed and manufactured to specifically meet its customers’ machining needs.

Tooling is a quintessential part of gear manufacturing, and one company’s needs are — more often than not — different from everyone else’s. That’s why it’s important to offer catered solutions that can be custom made — which is where Advent Tool & Manufacturing can make a difference. “We’re more of a problem-solving company when […]
Kenneth Carter

Services Profile: Dontyne Gears

Dontyne Gears pursues principles in design and machining techniques that are not yet part of the mainstream industry in order to gain a competitive advantage.

Dontyne Gears may not have decades of history behind it, but with the experience and skills of its parent company, Dontyne Systems, the fledgling business has made remarkable strides within the gear industry. “The gear industry is evolving, and Dontyne Gears works hard to remain at the forefront of that evolution through our skills, innovation, […]
Kenneth Carter

October 2019

Sona BLW

With advanced engineering at the core of its forging and gear divisions, Sona BLW
is constantly tackling demands while developing and implementing solutions for its customers.

Sona BLW CEO Sunjay Kapur proudly says his father, the founding chairman, had gears in his blood. And for a company whose offerings include the sale of 60 million gears and more across the globe, that statement might be the perfect way to describe the force behind the company’s worldwide success. “Today, we make 147 […]
Kenneth Carter

Root cause for noise excitation in geometrically-accurate (perfect) parallel-axes gearing

Theoretically, geometrically-accurate gearing that features zero base pitch variation promise to be noiseless, as no noise is produced by the gear mesh. In reality they can be noisy.

Gears are extensively used to transmit a rotation from a driving shaft to a driven shaft. Depending on the gear application, various configurations of the gear-shaft axes are distinguished. In the general case, gear-shaft axes cross one another; in one particular application, the gear shaft axes intersect one another; finally, in another particular application, the […]
Dr. Stephen P. Radzevich Ph.D., Dr. (Eng) Sci.

Using simulation to evaluate part green shape to reduce distortion during plug quenching

The commercially available heat-treatment simulation software, DANTE, has been used successfully to improve heat-treat processes and steel-part characteristics; this case study follows an example of applying the software to evaluate a real-world challenge.

Determining the heat-treatment geometry (green shape) for complex gears is not a trivial task. Mass distribution becomes critical in determining the uniformity of heat removal, and subsequently, the uniformity of solid-state phase transformations. The uniformity of transformation directly affects the distortion after quenching. For decades, distortion control during heat treating has been based on experience. […]
Justin Sims, Charlie Li, B. Lynn Ferguson

Filling Some Gaps in Spline Design Guidelines: Centering, Friction, and Misalignment

This paper provides an accurate method for calculating radial loads transmitted by straight-sided splines by means of the effective pressure angle calculation, enabling more accurate hoop-stress calculation for these splines.

Editor’s note: At the author’s request, some statements have been removed for clarity since the article was originally published in October, 2019. International spline standards such as ISO 4156, ISO 14, ANSI B92.2, and SAE J499a have detailed definition of two-dimensional spline geometry but cover only the most basic axial effects such as helix error. Other […]
Stephen McKenny

September 2019

JTEKT Toyoda Americas Corporation

For more than 70 years, JTEKT Toyoda Americas Corporation has been a world leader in machine-tool manufacturing that includes its roots in grinding machine technology to the advanced capabilities of its gear-skiving innovations.

Necessity may be the mother of invention, but for JTEKT Toyoda Americas Corporation, necessity became the catalyst for innovation. Toyoda Machinery was born from Toyota Motors when the car company was looking to bring the building of machine tools in-house to make car parts. “We were making machine tools originally for automotive, but then we […]
Kenneth Carter

Application of Finite Element Analysis for the Strain Wave Gear Tooth Surfaces Design and Modification

The gear industry has a well-established gearing theory, design code, and design simulation software to improve gear-transmission performance; however, the lack of similar tools restrains the development of the strain wave gear.

This paper represents the application of finite element analysis for the strain wave gear with modified conjugate tooth surfaces. The unmodified tooth profile is designed at a cross section derived from the fundamental kinematic model of the strain wave gear. The conjugation of the tooth profiles has been verified by the plane stress finite element […]
Dr. Zhiyuan Yu, Dr. Kwun-Lon Ting

Methods to Determine Form Diameter on Hobbed External Involute Gears

To assist gear designers to instantly verify the manufacturability of their designs, two methods are presented to calculate the manufactured form diameter given the design parameters of the gear and the hob.

In custom designs of external spur or helical gears, designers generally prefer a lower form diameter for greater transverse contact ratio. A larger root fillet radius and a higher root diameter are also preferred for higher root bending strength. The combination of the above three requirements can render the gear designs unable to be manufactured […]
Shuo “Will” Zhang

August 2019

Atlanta Gear Works

Atlanta Gear Works designs, engineers, builds, rebuilds, and repairs heavy industrial gearboxes for some of America’s leading manufacturers with one main goal — to minimize or prevent downtime.

Atlanta Gear Works set out in the beginning to do one thing and do it well: gearbox repair. But when the quality of the available components needed for their repairs wasn’t up to the company’s standards, Atlanta Gear Works decided to expand. “Originally, we just wanted to do gearbox repairs,” said Jack Conway, president of […]
Kenneth Carter

Design features of worm gearing composed of plastic and/or powder-metal components

The technology used in production of plastic gears, as well as powder-metal technology, imposes certain constraints on the design parameters of a worm
and of a mating gear.

This article deals with worm gearings in cases when the worm-gear pair is composed either of plastic or of powder-metal made components. The technology used in production of plastic gears, as well as powder-metal technology, imposes certain constraints on the design parameters of a worm and of a mating gear. Gears of this kind are […]
Dr. Stephen P. Radzevich Ph.D., Dr. (Eng) Sci.

Taking deburring to the next level

Recent developments from Helios Gear Products increase the productivity of the company’s Tecnomacchine CNC gear deburring technology.

Once a gear is created, deburring becomes a necessary step to ensure a gear’s accuracy. Traditionally, deburring has been done by hand, but that method can often take hours to complete. But with CNC technology, deburring can be done faster and with much tighter tolerances than could ever be accomplished manually. CNC machines are becoming […]
Gear Solutions staff

July 2019

Artec Machine

For nearly 50 years, Artec Machine Systems has been trusted for engineering design, parts, field repair, and maintenance of all types of heavy gear systems.

Gears are essential parts to the workings of countless machines, but when those machines are dependent on specifically designed gears, then service and repair can become a special niche. For Artec Machine, servicing equipment furnished with specially engineered gearing is at the very heart of what the company does. “We consider ourselves a leader on […]
Kenneth Carter

Lean Heat Treatment for Distortion Control

Proper control of heat treat distortion is of key importance to reduce production costs in gear manufacturing.

Controlling distortion is of key importance during the case hardening process for the production of gear components. By effective control of distortion and the variation of distortion, significant costs in post-heat treatment machining processes can be avoided. In some cases, it is even possible to eliminate all post- machining operations. In other cases, it may […]
Dr. Volker Heuer, David Bolton

Inspection & Metrology: ‘We must never stand still’

Metrologists take on new, frequent challenges
for quality control.

Small series and prototype production at ZF Friedrichshafen AG create new challenges for quality control time and again: measurement programs for new components need to be created every day. ZF metrologist Mehmet Akol accepts these challenges with unrelenting curiosity and uses ZEISS training courses to help him. Whether it’s parts for a bus, train, or […]
ZEISS Industrial Quality Solutions

Tooling & Workholding: Making Out-of-Round Parts Round

Several methods are available to face the difficulties presented by today’s thin-walled parts.

One of the most vexing problems in machining today is how to most efficiently make an out-of-round part round. In the days of thick-walled tubing or cut slugs, this manufacturing task presented little difficulty, but with today’s thin walled near-net-shape parts, the difficulties mount. Fortunately, we have developed several ways to make this task much […]
David A. Stokely

Tooling Workholding: A new solution for bevel gears

Precision grinding on the Haas Multigrind® increases surface quality and component accuracy.

The creativity of the designers knows no bounds with new drive element and gear geometries. Faced with constantly increasing demands from a wide variety of industrial sectors, today solutions are being sought that often cause major problems in production. The trend toward special products, small and special series, prototypes, and test setups is omnipresent. But […]
Zita Bader

Online exclusive: How many mils is your coating?

Coating can play a critical role in the prevention of wear or corrosion, so it’s important that coating thickness is measured in a quick and economical way to ensure efficiency.

Instantaneous handheld coating thickness gauges that can be operated by virtually any technician deliver lab-quality readings even on curved and complex surfaces like gears. From the job shop to the robotic assembly floor, it is vital that the product be made well and correctly coated for protection, aesthetics, and performance. So, industries such as automotive, […]
Del Williams

Tooling & Workholding: A success story: Low-deformation workpiece clamping

Before an optimum clamping solution can be defined, many requirements of the workpieces, type, machine frequency, and process-change integration must be properly addressed.

Those who want to turn, mill, or grind rings, flanges, housings, or other thin-walled parts will quickly reach the limits of what is possible using conventional lathe chucks or face plates: The parts are deformed during the clamping process; shaping and geometric tolerances are difficult to keep to, and the interfering contours of the clamping […]
Steve Hartung

June 2019

NORD Gear Corporation

NORD Gear Corporation markets and produces a complete product line of mechanical and electrical drive components including quality gear reducers, electric motors, AC Vector drives, and distributed drive technology.

For customers of NORD Gear Corporation, the company has 20 million reasons why it’s the right fit for their needs. “NORD’s philosophy to the gear manufacturing industry is really to have a flexible product,” said James Wubbolding, vice president of sales at NORD. “Our gear product range has about 20 million different combinations, and the […]
Kenneth Carter

Two-Probe Pitch Inspection Method For Large Gears

Highlighting merits of the two-probe index inspection method for large gears with a cursory review of the single-probe pitch inspection methodology, breakdown of tooth index characteristics, and a cross-reference of the single- and two-probe inspection methods.

A gear’s pitch (a k a index or spacing) accuracy is one of the most fundamental gear characteristics affecting its performance. Pitch errors affect the transmission accuracy, vibration, noise, and even the load carrying capacity. No wonder gear designers, manufacturers, and users pay close attention to pitch quality. Nowadays, there are many different pitch measuring […]
Yefim Kotlyar, Christoph Donner

Chamfer Hobbing, Perfect Timing

New Chamfer Hobbing adds a highly desirable process to the integrated hobbing and chamfering options now available to gear manufacturers — just in time for eDrives.

New gearbox developments, particularly for eDrives, are creating a whole new set of gear design and manufacturing criteria. Compact gearbox design is paramount, and the requirements can include gears designed for high torque on one side and high RPM on the other side. To ensure optimum power transmission, producing defined chamfers with tight tolerances is […]
Gottfried Klein

May 2019

Stace-Allen Chucks

Although it started out manufacturing precision power chucks, Stace-Allen Chucks has expanded into workholding – designing and manufacturing custom solutions to meet its customers’ demands.

Stace-Allen Chucks has been designing and manufacturing chucks for more than 70 years, but the company is so much more than that. “We are a highly specialized workholding company,” said Phil Grimes, president of Stace-Allen Chucks. “We have an engineering department, and we design specialty workholding. We still do our chucks; we still do our […]
Kenneth Carter

Residual Stresses in Case Hardened Steel Gears

Gears machined from forged billet and as-received bar develop tensile residual stress in the core of the gear following full heat treatment.

Aerospace gear components are required to demonstrate excellent load-carrying and endurance characteristics. Case-hardened steels are often used for these parts. During the manufacturing process of case-hardened steel gears, residual stresses are developed. The nature and distribution of these stresses are known to have a significant effect on distortion during heat treatment and machining processes. The […]
David Easton, Salah Rahimi, Chris Aylott, Brian Shaw

Choosing the proper grinding wheel

Experts with Norton | Saint-Gobain Abrasives discuss the challenges of gear grinding and how advances in technology are improving the efficiency of grinding methods.

Methods of gear grinding have changed over the years. As manufacturing standards get tighter, the right machines and abrasives needed to meet specifications have become even more critical. Product Manager Josh Fairley and Senior Application Engineer Phil Plainte with Norton | Saint-Gobain Abrasives share their expertise on how gear grinding — as well as using the […]
Kenneth Carter

Why are Today’s Hypoids the Perfect Crossed-Axes Gear Pairs?

Gear scientists, gear engineers, and gear manufacturers have worked successfully for many decades on finding the optimal flank forms and the optimal non-conjugate flank surface interaction.

In 1924, Ernest Wildhaber, a well-known gear scientist, invented hypoid gearing. Compared to spiral bevel gears, hypoid gears provide an offset that allows lowering of the body of rear wheel drive vehicles by 50mm or more. This is possible because the propeller shaft between engine/transmission and the driving axle is not positioned at the center […]
Dr. Hermann J. Stadtfeld

April 2019

Weiler Abrasives

With a history that dates back more than century, Weiler Abrasives has become a global market leader in abrasives, delivering innovative solutions to customers in targeted end markets.

Weiler Abrasives has worn many hats dating back to its original roots in 1898, but gear grinding has become one of the company’s key initiatives. “We chose gear grinding for several reasons,” said TJ Boudreau, category manager with Weiler Abrasives. “Our unique vitrified technology gives our gear-grinding products significant advantages. Additionally, it complements our technical […]
Kenneth Carter

Increasing Static Friction with Laser

High static friction is important for improving safety and reducing costs.

Flat and curved surfaces with functionality of high static friction are increasingly needed for force-fitted nonslip power transmissions. The motivation is driven by the desire to have a higher safety of function and further cost reductions in manufacturing. Expensive solutions such as diamond layers, diamond coatings, or form-fitting design are increasingly being substituted. A modified […]
Gerhard Flores

Hydraulic workholding takes hold

New Gleason hydraulic workholding solutions are becoming an attractive alternative to traditional mechanical systems in an increasingly wide range of gear-manufacturing applications.

In the brave new world of smart factories, Internet 4.0 and highly automated machines and cells, workholding rarely gets top billing. It’s surprising that workholding gets so little attention, given the profound impact it can have on reducing cycle times, scrap, and ultimately, cost per workpiece. Fortunately, most gear manufacturers in recent years have begun […]
Peter Harrison

Still Stuck with Hand Deburring?

With hand deburring, consistent quality and steady volume are vital concerns.

No blueprint ever revealed, nor engineer ever designed, a part with burrs. It is only after a process is selected for making a part that the burring issues become obvious. Veteran designers have learned that even when a deburring process is planned, chances are high that additional burr developments will come to light needing more […]
Wayne Moore

March 2019

General Broach Company

When it comes to broaching, General Broach Company is able to find the best machine and best tool design to fit the customer’s need.

General Broach Company General Manager Larry Stover freely admits that “broachable” isn’t a word, but it still sums up what the company is all about. “We are going to provide a quality product that is going to lower the cost per part,” Stover said. “We specialize in pot broaching especially. I know a lot of […]
Kenneth Carter

Industrial gear lubricants face formulation challenges

Moisture, temperature, viscosity, filtration, and base oil are some of the factors that need to be considered.

Gears transmit motion from one shaft to another or from a rotating shaft to a reciprocating element. Gears transmit power, change speed, change force (torque) or change direction. They operate under a myriad of operating cycles, loads, speeds and temperatures (see Gear Basic Terminology below). Gear lubricants increase the durability of equipment by preventing gear […]
Lawrence Ludwig Jr., Nancy McGuire

Advantages of a dual-screw H-Frame broaching machine

The BMS Dual-Drive is an electromechanically powered, table-up vertical broaching machine for all types of internal broaching applications.

Like any industry, in the machine-tool industry, the needs of the market drive new designs and the development of new technologies. Naturally, everyone wants machines to be less expensive to operate, to require less maintenance, and to be easier and safer to operate. They want a machine to take up less floor space and to […]
Matt Egrin

Streamlining safety for high-speed/small-footprint milling machines

High torque retention knobs are a vital anchor for safety between machine and spindle for high-RPM mills.

Safety in design is critical to CNC milling operations end products as well as to the machine’s profitability. As the trajectory of today’s new milling technology trends toward machines producing extremely high speeds/high-RPM within a smaller overall foot print, potential safety issues can’t be ignored. Loose tools moving fast could present the potential for a […]
John Stoneback

February 2019


Marposs has become a global leader for the supply of high-precision equipment for inspection, measurement, and control in the production environment.

In order to maintain its position as a world leader in the field of high-precision equipment for measurement, Marposs always looks for the right blend between experience and innovation. “Our mission is mainly to provide high-precision metrology equipment for machine control and part inspection in the shop floor environment,” said Matteo Zoin, senior manager, head […]
Kenneth Carter

Integrating Non-Contact Metrology in the Process of Analysis and Simulation of Gear Drives

The application of non-contact metrology allows a very fast collection of points on the measured gear-tooth surfaces with data rates that can be as high as millions of points per second — this new technology provides a wealth of information on gear geometry.

Speed and accuracy are critical factors for gear inspection. The faster the inspection process, the larger number of gear units can be inspected. The accuracy of the inspection process also plays a fundamental role to identify any possible defect in the production line and before the gearbox is assembled and further tested. The technology of […]
Alfonso Fuentes-Aznar, Ignacio Gonzalez-Perez

Design features of perfect gears for crossed-axes gear pairs

To improve the accuracy and performance of gears that operate on crossing axes of rotation, gears should be designed so they align to the three fundamental laws of gearing.

Gearings that operate on crossing axes of rotation of a gear and a mating pinion have been known for centuries. Common sense and accumulated practical experience are the two foundations for the adopted practice of designing gears in ancient times. Such a practice was permissible as the input and output rotations at that time were […]
Dr. Stephen P. Radzevich Ph.D., Dr. (Eng) Sci.

January 2019

Precision Gage Company

After 70 years, Precision Gage Company brings quality gear inspection to the industry, whether it be dimension-over-wires gages or fully-automated dual-flank composite test systems.

It’s a testament to Precision Gage Company that, from its beginnings in a living room in Chicago, it is celebrating its 70th year in the industry this year. Precision Gage has prospered by offering common-sense inspection solutions for manufacturing, especially with regard to gear inspection, according to RG Layland, director of business development for Precision […]
Kenneth Carter

Magnetic Barkhausen Noise as an Alternative to Nital Etch for the Detection of Grind Temper on Gears

MBN is quantitative, repeatable, non-destructive, and it is easily automated, thus removing operator influence as a variable.

The detection and prevention of grinding burn is critical to the production of ground gears of all types and sizes. Overheating during grinding, or grind temper, results in undesirable microstructure, hardness, and stress characteristics both on and below the surface. These characteristics result in failure modes on precision surfaces, which typically require high performance under […]
James Thomas, Stephen Kendrish

Grading the strength of steel

Newly developed high-strength steel for car powertrain and transmission components includes three grades – knowing the difference will help you meet your quality goals.

Vehicle manufacturers are faced with a difficult task of significantly improving fuel economy and safety while maintaining competitive position in the market. This can be accomplished, among other things, by using higher strength steel for car and truck. Newly developed high strength steel for car powertrain and transmission components (GEAR-Steel) can help accomplish just that. […]
Gregory Vartanov

Measuring Tooth Flank Roughness

The Contact Stylus Profilometer provides a pragmatic, accurate and reproducible tooth flank roughness measurement.

Gear performance has continuously increased over the past two decades. Improvements in metals, heat treatments, geometry, and lubrication are just a few of the sources of these improvements. For gears operating in high load, EHL-type conditions, tooth flank finishes have experienced a similar improvement trend. These tooth flank finish improvements minimize the risk of surface […]
Mark Michaud