A technical overview of the three principal face couplings (Hirth, Coniflex, and Curvic), comparing their tooth geometries, self-centering behavior, and Gleason’s cutting and grinding processes for manufacturing them.




An excerpt from Gear Technology Solutions by Dr. Hermann J. Stadtfeld exploring the mathematics behind conjugate bevel and hypoid gears—from the fundamental laws of gearing and the conditions for perfect conjugacy to why real-world power transmissions require deliberate crowning rather than theoretically exact conjugate designs.
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Through loaded tooth contact analysis of two applications, this paper demonstrates that crown gears can match bevel gear load capacity while offering meaningful advantages in weight reduction, axial-force-free pinion mounting, and assembly simplicity.
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20NiMo9-7 alloy achieves up to 48 percent higher fatigue strength than conventional carburizing steels in the as-carburized condition, eliminating the need for shot peening and grinding in automotive gear applications.
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This excerpt from Gear Technology Solutions explains how oversized cutter blade edge radii cause root interference in bevel gears, and how to select correct radii to avoid noise, flank damage, and tooth fracture.
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As a community, we gear engineers collaborate and share ideas to progress our collective capability. Technology progresses based on our efforts, and we have seen solid advances in the performance of our products as they become quieter, cheaper, more efficient, and more power dense. The pages of this magazine (past and present editions) are filled with examples where talented engineers have dug deeper into a subject using a more precise approach to a particular area concerning gear performance. The implied belief is always that greater precision (complexity) in the calculations brings greater accuracy (alignment with reality).

From its origins as a small machine shop to becoming a global leader in precision engineering, Gleason Corporation has continuously redefined the industry. This journey, marked by pioneering inventions and strategic expansions, has left an indelible mark on sectors ranging from automotive and aerospace to robotics and renewable energy.

As the gear and power transmission industries evolve, companies worldwide face a critical challenge: how to ensure the workforce is skilled, prepared, and ready to tackle increasingly complex manufacturing processes. From digital manufacturing and automation to generational turnover, the demand for technically proficient employees has never been higher. In response, the Motion + Power Technology Association (MPMA) redeveloped its Workforce Training Series, modernizing its most popular on-demand courses with updated content, high-quality media, and a flexible, self-paced delivery model.

Gas carburizing has been around for a long time. One could argue that gas carburizing is the most common heat treating process. Heat treaters performing gas carburizing are often characterized by a dirty environment, hazy surroundings, and that “smell.” While the product quality may be acceptable, gas carburized parts do come with some challenges, like excessive intergranular oxidation (IGO) or intergranular attack (IGA), which is often ground off. Low-pressure carburizing (LPC) has proven to be a much cleaner and very capable alternative process. Most furnace companies have combined LPC with high pressure gas quenching, which moved carburizing from the dark back room to a relatively “clean room” environment. However, there is still a strong need for oil quenching, which is the common feature of the long used standard integral-quench (IQ) furnace.
The demand for double helical gears in planetary gear systems for engines in the civil aerospace industry is increasing. Innovative grinding processes and state-of-the-art technologies ensure precision, reduced weight, and improved cost efficiency. Learn how KAPP NILES reduced the gap width from 30 mm to 15 mm.
Discover four diagnostic enhancement tools that move RX® endothermic gas atmosphere generator operations from preventative to predictive maintenance. Learn how monitoring dew point by retort, comparing equal flow, tracking tube performance, and measuring outlet temperatures prevent costly failures while ensuring consistent, high-quality carrier gas production.
The right hob can make a measurable difference in gear production. Watch the video to see how Star SU combines advanced hob technology with application expertise to help manufacturers get more from every gear cutting operation.
The Intra SFTX twin-spindle single-flank testing system is engineered for advanced gear quality testing and NVH analysis of demanding e-drive gear applications. Combining Transmission Error (TE) and Torsional Acceleration (TA) measurements, it delivers fast, precise diagnostics and detailed order analysis, quickly identifies critical gear issues, enhances traceability, and helps prevent costly defects from reaching end-of-line (EOL) testing.
The 80PS Power Skiving and Hobbing Machine is specifically engineered for power skiving, hobbing, and profile milling of small internal and external gears. Configured specifically for the demands of humanoid robotic gear production, it delivers outstanding performance and process stability for gears used in strain wave, planetary, and cycloidal gearboxes, as well as other high-precision applications of comparable size — even when machining fine-pitch gears and thin-walled components.
At Gear Headquarters, quality is the foundation of everything they do. Based in Kansas City, the shop manufactures spur, helical, double-helical, herringbone, bevel, internal, spline, and worm gears, sprockets, and timing belt pulleys.

GWJ Technology GmbH has launched completely redesigned websites for its eAssistant and TBK brands,as well as its corporate website. With this relaunch, the company introduces a modern, user-friendly design and optimized content that makes it easier than ever to access technical information and engineering software solutions. The new websites focus on intuitive navigation and a clear information structure, enabling users to quickly find the content they need.
Dec 8, 2026 - Dec 9, 2026

CTI Symposium Berlin offers active discussions on the latest technologies and strategies on automotive transmissions and HEV & EV drives for passenger cars and commercial vehicles. At CTI Symposium Berlin, more than 650 senior experts and decisionmakers from OEMs, Tier 1 suppliers, technology companies, and research institutions come together to discuss the latest developments in electrified drivetrains, hybrid technologies, energy systems, software integration, and future mobility strategies.
Sep 22, 2026 - Sep 23, 2026
Oct 12, 2026 - Oct 14, 2026
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