January/February 2010

Where Are We Now

The struggles of the manufacturing economy in 2009 are well documented. Even among those of us with long careers, most of us have never seen activity come to a screeching halt the way it did last year. 2009 was tough on all of us. So, what should we expect in 2010?

Area of Existence of Involute Gears

This paper presents a unique approach and methodology to define the limits of selection for gear parameters. The area within those limits is called the “area of existence of involute gears” (Ref. 1). This paper presents the definition and construction of areas of existence of both external and internal gears. The isograms of the constant operating pressure angles, contact ratios and the maximum mesh efficiency (minimum sliding) isograms, as well as the interference isograms and other parameters are defined. An area of existence allows the location of gear pairs with certain characteristics. Its practical purpose is to define the gear pair parameters that satisfy specific performance requirements before detailed design and calculations. An area of existence of gears with asymmetric teeth is also considered.

Producing Profile and Lead Modifications in Threaded Wheel and Profile Grinding

Modern gearboxes are characterized by high torque load demands, low running noise and compact design. In order to fulfill these demands, profile and lead modifications are being applied more often than in the past. This paper will focus on how to produce profile and lead modifications by using the two most common grinding processes—threaded wheel and profile grinding. In addition, more difficult modifications—such as defined flank twist or topological flank corrections—will also be described in this paper.

Design, Development and Application of New, High-Performance Gear Steels

QuesTek Innovations LLC is applying its Materials by Design computational design technology to develop a new class of high-strength, secondary hardening gear steels that are optimized for high-temperature, low-pressure (i.e., vacuum) carburization. The new alloys offer three different levels of case hardness (with the ability to “dial-in” hardness profiles, including exceptionally high case hardness), and their high core strength, toughness and other properties offer the potential to reduce drivetrain weight or increase power density relative to incumbent alloys such as AISI 9310 or Pyrowear Alloy 53.

Sizing Up Big Gears

Quality, materials and technology continue to challenge the big gear manufacturing market.

Wind Turbine Pitch and Yaw Drive Manufacturers Draw Breath as Market Slows

The global wind energy market has seen average growth rates of 28 percent over the last 10 years, according to the Global Wind Energy Council (GWEC), creating major challenges for the component supply industry. GWEC also forecasts an average growth rate of 22 percent for the next five years, which if realized, will continue to put pressure on suppliers of turbine components.

Tapping into the Wind Gearbox Supply Chain

Although typically considered a late bloomer in the call to wind energy arms, the United States is now the number one wind power producer in the world with over 25,000 MW installed by the end of 2008, according to the Global Wind Energy Council in January 2009.

Global Positioning System: The Early Years

Before retiring from St. Louis Gear in 2000, Roy Harmon liked to tinker. Since the customer base at the time was seasonal, Harmon was looking for a project to keep himself busy. The engineer decided to challenge himself by designing a “South Pointing Chariot,” a device he had read about in the book The Evolution of the Gear Art by Darle Dudley.

All-in-One Broaching Capability

Faster, more efficient manufacturing offered with table-top design from American Broach & Machine.

Product News

The complete Product News section from the January/February 2010 issue.

Industry News

The complete Industry News section from the January/February 2010 issue of Gear Technology.

Calendar

The technical calendar from the January/February 2010 issue of Gear Technology.