March/April 2009

Tale of Two Gear Industries

The good news and the bad news about the gear industry and its role in the overall economy.

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.

Grinding Induced Changes in Residual Stresses of Carburized Gears

This paper presents the results of a study performed to measure the change in residual stress that results from the finish grinding of carburized gears. Residual stresses were measured in five gears using the x-ray diffraction equipment in the Large Specimen Residual Stress Facility at Oak Ridge National Laboratory.

Hob Tool Life Technology Update

The method of cutting teeth on a cylindrical gear by the hobbing process has been in existence since the late 1800s. Advances have been made over the years in both the machines and the cutting tools used in the process. This paper will examine hob tool life and the many variables that affect it. The paper will cover the state-of-the-art cutting tool materials and coatings, hob tool design characteristics, process speeds and feeds, hob shifting strategies, wear characteristics, etc. The paper will also discuss the use of a common denominator method for evaluating hob tool life in terms of meters (or inches) per hob tooth as an alternative to tool life expressed in parts per sharpening.

Got Lean, Six Sigma - Here's Another Theory

Most readers are at least familiar with continuous improvement programs such as lean and six sigma. Perhaps your shop or company is well along in the implementation of one or the other—if not both. But what about theory of constraints (TOC), introduced in Dr. Eliyahu Goldratt’s 1984 book, The Goal? Despite its rather negative-sounding name, this continuous improvement process has much to offer manufacturers of all stripes. And when combined with lean and six sigma, the results can be dramatic. Dr. Lisa Lang, a TOC consultant and speaker, explains why and how in the following Q&A session with Gear Technology.

The Changing Industrial Landscape

Companies weigh in on green technology and sustainable efforts.

Honk if You Love Gears

The Addendum Team announces plans for the Gear Vanity Plate Hall of Fame.

Product News

The complete Product News section from the March/April 2009 issue of Gear Technology.

Cutting Edge Grinders Are Great - But How's Your Workholding

Capacity is key today, and the best way to ensure that you are squeezing every dime out of that new machine is to complement it with innovative workholding.

Industry News

The complete industry news section from the March/April 2009 issue of Gear Technology.

Wind, Alt-Energy Themes Sweep Through Hannover Fairgrounds

As an indicator of what’s up-and-coming in the manufacturing technology world, Hannover Messe 2009 reflects the prominence of alternative energy and efficiency.

Calendar

The technical calendar from the March/April 2009 issue of Gear Technology.