| Gear Technology Magazine

The Call of Cuba

May 1, 2012

I’ve had the great fortune to visit many countries and experience their cultures, and I often tell stories based on those experiences. But when I begin to tell people about my most recent trip—to Cuba—their eyes light up, their attention sharpens and they lean forward with great interest and curiosity.

Gear Software - Without it, Hardware Goes Nowhere

May 1, 2012

Jack McGuinn

It’s a brave, new hardware-software world out there. Players in the worldwide gear industry who don’t have plenty of both run the risk of becoming irrelevant—sooner than later.

Full Speed Ahead

May 1, 2012

Matthew Jaster

Indexable carbide insert (ICI) cutting tools continue to play a pivotal role in gear manufacturing. By offering higher cutting speeds, reduced cycle times, enhanced coatings, custom configurations and a diverse range of sizes and capabilities, ICI tools have proven invaluable for finishing and pre-grind applications. They continue to expand their unique capabilities and worth in the cutting tool market.

Longitudinal Tooth Contact Pattern Shift

May 1, 2012

After a period of operation, high-speed turbo gears may exhibit a change in longitudinal tooth contact pattern, reducing full face width contact and thereby increasing risk of tooth distress due to the decreased loaded area of the teeth. But this can be tricky—the phenomenon may or may not occur. Or, in some units the shift is more severe than others, with documented cases in which shifting occurred after as little as 16,000 hours of operation. In other cases, there is no evidence of any change for units in operation for more than 170,000 hours. This condition exists primarily in helical gears. All recorded observations here have been with case-carburized and ground gear sets. This presentation describes phenomena observed in a limited sampling of the countless high-speed gear units in field operation. While the authors found no existing literature describing this behavior, further investigation suggests a possible cause. Left unchecked and without corrective action, this occurrence may result in tooth breakage.

Application of the First International Calculation Method for Micropitting

May 1, 2012

The first edition of the international calculation method for micropitting—ISO TR 15144–1:2010—was just published last December. It is the first and only official, international calculation method established for dealing with micropitting. Years ago, AGMA published a method for the calculation of oil film thickness containing some comments about micropitting, and the German FVA published a calculation method based on intensive research results. The FVA and the AGMA methods are close to the ISO TR, but the calculation of micropitting safety factors is new.

An Innovative Way of Designing Gear Hobbing Processes

May 1, 2012

In today’s manufacturing environment, shorter and more efficient product development has become the norm. It is therefore important to consider every detail of the development process, with a particular emphasis on design. For green machining of gears, the most productive and important process is hobbing. In order to analyze process design for this paper, a manufacturing simulation was developed capable of calculating chip geometries and process forces based on different models. As an important tool for manufacturing technology engineers, an economic feasibility analysis is implemented as well. The aim of this paper is to show how an efficient process design—as well as an efficient process—can be designed.

Ask the Expert: High Ratio Hypoid Gear Efficiency

May 1, 2012

Our question this issue deals with high-ratio hypoid gears, and it should be noted here that this is a tricky area of gearing with a dearth of literature on the topic. That being the case, finding “experts” willing to stick their necks out and take on the subject was not a given.

Siemens Plant Management 101

May 1, 2012

Once upon a time there was a computer. This computer served as a conduit to waste a great deal of time through social networking and online video games. Still, there was always potential to turn these rather sedentary activities into something more positive and useful to mankind. Siemens may have stumbled upon such a concept.