A critical problem for wind turbine gearboxes is failure of rolling element bearings where axial cracks form on the inner rings. This article presents field experience from operating wind turbines that compares the performance of through-hardened and carburized materials. It reveals that through-hardened bearings develop WEA/WECs and fail with axial cracks, whereas carburized bearings do not. The field experience further shows that a carburized bearing with a core having low carbon content, high nickel content, greater compressive residual stresses, and a higher amount of retained austenite provides higher fracture resistance and makes carburized bearings more durable than through-hardened bearings in the wind turbine environment.

We're pleased to present the first-ever March issue of Power Transmission Engineering.

After a brief introduction to the importance of gear pumps in internal combustion engines, as well as in the most diverse hydraulic applications, a calculation method was applied that allows for sizing with considerably higher delivery rates. Upon identifying and analyzing a traditional pump, along with two construction solutions of asymmetric gear pumps, we then compared their related performances.

In most applications, gearbox reliability is critical to the productivity of the overall plant operation. So it follows that when industry is looking at the best ways to increase efficiency, reduce downtime, and increase profitability, gearbox performance and reliability are key factors. Designing for repair, and writing effective repair procedures, can speed the service time, and provide a quality refurbishment. The best practices listed in this article are proven, effective methods used to install and remove bearings, seals, gears, couplings and shafts within a gearbox.

We are pleased to present our first annual Engineering Showcase, a celebration of some of the leading products and companies in mechanical power transmission. In the pages that follow, you’ll find examples of engineering excellence and technological know-how in the field of gears, drives, couplings, machine parts and other mechanical components.

IFPE offers the right balance of technology and education.

This paper outlines the design considerations that go into construction of a drive system in order to explain the importance of specific data, why it is required, and where design freedom is necessary. Apart from loads and speeds, interface dimensions and site specific conditions are also needed. Deciding up front which gear rating practice to select can affect the torque capacity of the drive train by ~15%.

When software goes bad, what do we call it? System failure? Human failure? A virus? A number of words will work. How about this? Glitch. It has that onomatopoeic quality that fairly screams, Downtime! And with good reason -- software-generated miscalculations can have very expensive -- if not perilous -- repercussions.

A reader asks what are the required parameters to properly specify a gear.

Collaboration moves bearing modeling and simulation software forward