The author has written this book primarily from the viewpoint of analyzing vibrations on heavy industrial and mill gearing that may have been in service for a prolonged time. The purpose is to diagnose problems, especially the source or cause of failure. However, the principles and analysis techniques can be used for all types and sizes of gears, as well as for gear noise analysis.

For high-quality carburized, case hardened gears, close case carbon control is essential. While tight carbon control is possible, vies on what optimum carbon level to target can be wider than the tolerance.

When you to to IMTS, you expect to see hoopla. The mass of machines and bodies gathered in one place should create an unmistakable level of energy and enthusiasm. IMTS 2000 seemed uncharacteristically quiet...

Complete Technical Calendar for September/October 2000.

Increased productivity in roughing operations for gear cutting depends mainly on lower production costs in the hobbing process. In addition, certain gears can be manufactured by shaping, which also needs to be taken into account in the search for a more cost-effective form of production.

Welcome to Revolutions, the column that brings you the latest, most up-to-date and easy-to-read information about the people and technology of the gear industry.

One of the best ways to learn the ISO 6336 gear rating system is to recalculate the capacity of a few existing designs and to compare the ISO 6336 calculated capacity to your experience with those designs and to other rating methods. For these articles, I'll assume that you have a copy of ISO 6336, you have chosen a design for which you have manufacturing drawings and an existing gear capacity calculation according to AGMA 2001 or another method. I'll also assume that you have converted dimensions, loads, etc. into the SI system of measurement.

Fig. 1 shows the effects of positive and negative rake on finished gear teeth. Incorrect positive rake (A) increase the depth and decreases the pressure angle on the hob tooth. The resulting gear tooth is thick at the top and thin at the bottom. Incorrect negative rake (B) decreases the depth and increases the pressure angle. This results in a cutting drag and makes the gear tooth thin at the top and thick at the bottom.

When you have a multi-million-dollar transfer line sitting on the shop floor waiting for gears that might take up to two months to get, you have a costly bottleneck.

In 1993, M & M Precision Systems was awarded a three-year, partial grant from the Advanced Technology Program of the Department of Commerce's National Institute of Standards and Technology (NIST). Working with Pennsylvania State University, M&M embarked on a technology development project to advance gear measurement capabilities to levels of accuracy never before achieved.