The purpose of gear inspection is to:
Assure required accuracy and quality,
Lower overall cost of manufacture by controlling rejects and scrap,
Control machines and machining practices and maintain produced accuracy as machines and tools wear,
Determine hear treat distortions to make necessary corrections.
The design of any gearing system is a difficult, multifaceted process. When the system includes bevel gearing, the process is further complicated by the complex nature of the bevel gears themselves. In most cases, the design is based on an evaluation of the ratio required for the gear set, the overall envelope geometry, and the calculation of bending and contact stresses for the gear set to determine its load capacity. There are, however, a great many other parameters which must be addressed if the resultant gear system is to be truly optimum.
A considerable body of data related to the optimal design of bevel gears has been developed by the aerospace gear design community in general and by the helicopter community in particular. This article provides a summary of just a few design guidelines based on these data in an effort to provide some guidance in the design of bevel gearing so that maximum capacity may be obtained. The following factors, which may not normally be considered in the usual design practice, are presented and discussed in outline form:
Integrated gear/shaft/bearing systems
Effects of rim thickness on gear tooth stresses
Resonant response
The quality of gearing is a function of many factors ranging from design, manufacturing processes, machine capability, gear steel material, the machine operator, and the quality control methods employed. This article discusses many of the bevel gear manufacturing problems encountered by gear manufacturers and some of the troubleshooting techniques used.
Taxes may be one of the only two sure things in life, but that doesn't make them popular. Nobody is happy to pay them, and the bigger the amount due, the unhappier the taxpayer. Conversely, politicians know that coming out in favor of a tax cut is the equivalent of voting for apple pie and motherhood. It's a sure-fire success at the ballot box.
What was once recognized as the unique
genius of America is now slipping away
from us and, in many areas, is now seen as a "second rate" capability. Unless
action is taken now, this country
is in real danger of being unable to regain its supremacy in technological development and economic vigor. First Americans must understand the serious implications of the problem; and second, we must dedicate ourselves to national and local actions that will ensure a greater scientific and
technological literacy in America.