TOPICS CALENDAR BUYER'S GUIDE AGMA

Superfinishing

EVENT | 2023-05-12

Fabtech 2024

Fabtech provides a 'one-stop-shop' for metal forming, fabricating, welding, and finishing trade show. Attendees can meet with 1,300+ suppliers, discover innovative solutions, and find the tools to improve productivity and increase profits. There is no better opportunity to network, share knowledge and explore the latest technology.

PRODUCT NEWS | 2022-10-12

Nagel and Gehring Partner for Honing, Superfinishing and Electromobility Innovations

Nagel and Gehring recently shared innovative technologies during AMB 2022 including new standards in efficient honing, maximum flexibility in the superfinishing of flat, concave, and spherical surfaces, and efficient internal and external honing of workpieces.

TECHNICAL ARTICLES | 2022-07-15

IGS to Increase Wind Gearbox Torque Density

To increase cost efficiency in wind turbines, the wind industry has seen a significant rise in power density and an increase in the overall size of geared components. Current designs for multimegawatt turbines demand levelized cost of energy (LCOE) reduction, and the gearbox is a key part of this process. Since fatigue failures nearly always occur at or near the surface, where the stresses are greatest, the surface condition strongly affects the gear life. Consequently, an improved surface condition effectively avoids major redesign or increased material cost due to an increase in part size. Additional finishing methods such as shot peening (SP) and superfinishing (SF) significantly increase the gear load capacity, but these effects have not yet been adequately considered in the current ISO 6336 standard or in any other gear standards. The combination of SP followed by SF will be described here as an “improved gear surface” (IGS).

INDUSTRY NEWS | 2020-04-14

Ingersoll Adds Insert to Superfinishing High-Feed Face Mills

Ingersoll has introduced its Gold-Max 4 FFIN. Features include cutting diameters from 2.00” thru 8.00”, two insert types, eac...

FEATURE ARTICLES | 2017-01-01

Oil-Out Endurance Under the Lens

Oil-out conditions, or conditions in which an aircraft is operating without any oil in its gearbox or transmission, are devastating for an aircraft's hardware. Even the sturdiest gears usually can't last 30 minutes under such conditions before they catastrophically fail, and the whole system usually follows shortly after. That doesn't leave pilots with a whole lot of time to find a suitable location to land in the case of an oil-out emergency.

TECHNICAL ARTICLES | 2012-10-01

Repair of High-Value, High-Demand Spiral Bevel Gears by Superfinishing

Following is a report on the R&D findings regarding remediation of high-value, high-demand spiral bevel gears for the UH–60 helicopter tail rotor drivetrain. As spiral bevel gears for the UH–60 helicopter are in generally High-Demand due to the needs of new aircraft production and the overhaul and repair of aircraft returning from service, acquisition of new spiral bevel gears in support of R&D activities is very challenging. To compensate, an assessment was done of a then-emerging superfinishing method—i.e., the micromachining process (MPP)—as a potential repair technique for spiral bevel gears, as well as a way to enhance their performance and durability. The results are described in this paper.

TECHNICAL ARTICLES | 2012-08-01

Case Study Involving Surface Durability and Improved Surface Finish

Gear tooth wear and micropitting are very difficult phenomena to predict analytically. The failure mode of micropitting is closely correlated to the lambda ratio. Micropitting can be the limiting design parameter for long-term durability. Also, the failure mode of micropitting can progress to wear or macropitting, and then go on to manifest more severe failure modes, such as bending. The results of a gearbox test and manufacturing process development program will be presented to evaluate super-finishing and its impact on micropitting.

TECHNICAL ARTICLES | 2009-09-01

Gear Corrosion During the Manufacturing Process

No matter how well gears are designed and manufactured, gear corrosion can occur that may easily result in catastrophic failure. Since corrosion is a sporadic and rare event and often difficult to observe in the root fillet region or in finely pitched gears with normal visual inspection, it may easily go undetected. This paper presents the results of an incident that occurred in a gear manufacturing facility several years ago that resulted in pitting corrosion and intergranular attack (IGA).

TECHNICAL ARTICLES | 2009-05-01

Repair via Isotropic Superfinishing of Aircraft Transmission Gears

The objective of this paper is to demonstrate that transmission gears of rotary-wing aircraft, which are typically scrapped due to minor foreign object damage (FOD) and grey staining, can be repaired and re-used with signifi cant cost avoidance. The isotropic superfinishing (ISF) process is used to repair the gear by removing surface damage. It has been demonstrated in this project that this surface damage can be removed while maintaining OEM specifications on gear size, geometry and metallurgy. Further, scrap CH-46 mix box spur pinions, repaired by the ISF process, were subjected to gear tooth strength and durability testing, and their performance compared with or exceeded that of new spur pinions procured from an approved Navy vendor. This clearly demonstrates the feasibility of the repair and re-use of precision transmission gears.

TECHNICAL ARTICLES | 2009-03-01

The Effect of Superfinishing on Gear Micropitting

Results from the Technical University of Munich were presented in a previous technical article (see Ref. 4). This paper presents the results of Ruhr University Bochum. Both research groups concluded that superfinishing is one of the most powerful technologies for significantly increasing the load-carrying capacity of gear flanks.

TECHNICAL ARTICLES | 2009-01-01

The Capacity of Superfinished Vehicle Components to Increase Fuel Economy, Part I

This paper will present data from both laboratory and field testing demonstrating that superfinished components exhibit lower friction, operating temperature, wear and/ or higher horsepower, all of which translate directly into increased fuel economy.

TECHNICAL ARTICLES | 2008-09-01

Lapping and Superfinishing Effects on Surface Finish of Hypoid Gears and Transmission Errors

This presentation is an expansion of a previous study (Ref.1) by the authors on lapping effects on surface finish and transmission errors. It documents the effects of the superfinishing process on hypoid gears, surface finish and transmission errors.

TECHNICAL ARTICLES | 2008-03-01

Operational Condition and Superfinishing Effect on High-Speed Helical Gearing System Performance

An experimental effort has been conducted on an aerospace-quality helical gear train to investigate the thermal behavior of the gear system. Test results from the parametric studies and the superfinishing process are presented.

TECHNICAL ARTICLES | 2005-09-01

Gear Finishing with a Nylon Lap

The objective of this research is to develop a new lapping process that can efficiently make tooth flanks of hardened steel gears smooth as a mirror.

FEATURE ARTICLES | 2005-07-01

Superfinishing Gears - The State of the Art, Part II

In a previous article, the authors identified two misconceptions surrounding gear superfinishing. Here, they tackle three more.

FEATURE ARTICLES | 2003-11-01

Superfinishing Gears -- The State of the Art

Superfinishing the working surfaces of gears and their root fillet regions results in performance benefits.

TECHNICAL ARTICLES | 1986-11-01

Mirror Finishing of Tooth Surfaces Using A Trial Gear Grinder With Cubic-Boron-Nitride Wheel

In conventional gear grinders, grinding wheels with Alundum grains and a hardness of about 2000 HV have been used for finishing steel gears with hardnesses up to about 1000HV. In this case, the accuracy of the gears ground is greatly affected by wear of the grinding wheel because the difference in hardness is comparatively small when the gears are fully hardened.