Strength

GEAR TALK WITH CHUCK | 2019-07-26

Timely Course Corrections

Mrs. Curtis’ account of their family firm’s transition from general machining to noted gearbox manufacturer is an important reminder that success o...

GEAR TALK WITH CHUCK | 2019-07-05

Gear Origins: Graham Penning

For the last few years I have delivered a gear foundation course to both young and experienced engineers wanting to understand gear technology, and...

GEAR TALK WITH CHUCK | 2019-05-07

Dave Hinz — My Story

Sometimes there is a “gear guy” lurking inside an ordinary engineer. Risking the embarrassment of a poor result on an unexpected “pop quiz” was...

GEAR TALK WITH CHUCK | 2019-04-30

Hanspeter Dinner—My Story

It was the middle of December — rainy, dark, late, cold. My job with a roller coaster company was the wrong choice. I had a job interview with KISS...

GEAR TALK WITH CHUCK | 2019-03-26

Remembering the Giants

While writing about the “degrees of connection” between current industry leaders and th...

INDUSTRY NEWS | 2019-03-04

Ipsen Strengthens Customer Service Group with New Manager

Ipsen USA is pleased to announce the promotion of Matt Clinite from Midwest regional sales owner to Ipsen customer service sales manager,...

GEAR TALK WITH CHUCK | 2019-01-30

From Co-op to Vice President: Octave A. LaBath

I was attending the University of Cincinnati in the college of engineering. After my freshman year in 1960, I started my co-op job with the Cincinn...

GEAR TALK WITH CHUCK | 2018-11-27

Industrial Strength Good Deeds Part 1

The end-of-year hol...

GEAR TALK WITH CHUCK | 2018-10-16

Influence of Different Manufacturing Processes on Properties of Surface-Densified PM Gears

The properties of both shot-peened and cold rolled PM gears are analyzed and compared. To quantify the effect of both manufacturing processes, the tooth root bending fatigue strength will be evaluated and compared to wrought gears.

GEAR TALK WITH CHUCK | 2018-08-14

Finding the Right Combination

One of the hal...

GEAR TALK WITH CHUCK | 2018-07-03

Planetary Gears: Inside Information

The Story So Far

GEAR TALK WITH CHUCK | 2018-06-14

Options for Material Selection

Disclaimer: This is the policy I follow for material selection. Your situation may call for a different decision. You should not adopt this pol...

GEAR TALK WITH CHUCK | 2018-06-07

Hardenability 102

Material Grade in Gears

GEAR TALK WITH CHUCK | 2018-06-05

Hardenability 101

Material Grade in Gears

The reason not all gears can be made from the same material grade has to do with hardenability. We have long unde...

GEAR TALK WITH CHUCK | 2018-05-31

Parsing the Fine Print

If my last posting prompted you to look at a copy of a material cert, you probably noticed that the cert has much more information on it than just ...

GEAR TALK WITH CHUCK | 2018-05-10

What’s Your Angle?

Hulet self-unloader image courtesy of ASME. Interesting things happen when you start using “non-standard” gear geometry. As early as th...

GEAR TALK WITH CHUCK | 2018-05-03

That X Factor

Our international readers are no doubt chuckling over this silly, American “long addendum” terminology. The “civilized world” has long relied on a ...

GEAR TALK WITH CHUCK | 2018-05-01

Bending the Rules

In my last posting I advised designers to avoid relying on “rules of thumb” or computer coding when confronted with tough decisions. This admonitio...

GEAR TALK WITH CHUCK | 2018-04-26

Actions Have Consequences

The initial motivation for changing outside diameters was the avoidance of undercutting. Designers, engineers, and theoreticians quickly discovered...

GEAR TALK WITH CHUCK | 2018-04-25

The Long and Short of It

One of the problems with “tribal knowledge” is that the terminology can confuse those who are not fully immersed in that community. I have lost ...

GEAR TALK WITH CHUCK | 2018-04-17

How Many Teeth Do You Want?

Designing gears is somewhat of a mathematical puzzle. You have lots of interconnected factors to play with in hopes of finding the “best” overall s...

GEAR TALK WITH CHUCK | 2018-03-01

Out of Your Depth?

How did that over pin calculation work out? My congratulations if you managed to work your way through it without tearing your hair out. Guess what...

GEAR TALK WITH CHUCK | 2018-01-23

The First Step is Easy

When I started writing my gear book back in 1986, the mission was to provide enough information for a person new to the gear trade to tell if someo...

GEAR TALK WITH CHUCK | 2017-11-09

Write it Down

Gear Expo was a wonderful opportunity to meet old friends and make new ones. While I was out collecting swag, purely in support of my reporting dut...

GEAR TALK WITH CHUCK | 2017-09-14

Developing Resilience

For many years, “robust” was a popular business buzz word. The idea was to make certain your procedures and processes were “strong” enough to withs...

TECHNICAL ARTICLES | 2017-05-01

Inclusion-Based Bending Strength Calculation of Gears

Reduced component weight and ever-increasing power density require a gear design on the border area of material capacity. In order to exploit the potential offered by modern construction materials, calculation methods for component strength must rely on a deeper understanding of fracture and material mechanics in contrast to empirical-analytical approaches.

GEAR TALK WITH CHUCK | 2017-04-04

What Makes a Good Design?

In my last post I insisted that good design wins in the marketplace. As a student of automotive history, I am compelled to admit that some very gre...

GEAR TALK WITH CHUCK | 2017-01-12

The Essential Gear Book?

Continuing our discussion of gear training… What one book would you advise a newbie to purchase, read, and keep handy in the years ahe...

TECHNICAL ARTICLES | 2016-11-01

Calculation of the Tooth Root Strength of Worm Wheel Teeth Based on Local Stresses

How local stresses obtained from FEA can be used to determine fatigue strength of worm wheel teeth.

TECHNICAL ARTICLES | 2016-09-01

Increased Tooth Bending Strength and Pitting Load Capacity of Fine-Module Gears

The common calculation methods according to DIN 3990 and ISO 6336 are based on a comparison of occurring stress and allowable stress. The influence of gear size on the load-carrying capacity is considered with the size factors YX (tooth root bending) and ZX (pitting), but there are further influences, which should be considered. In the following, major influences of gear size on the load factors as well as on the permissible tooth root bending and contact stress will be discussed.

TECHNICAL ARTICLES | 2016-09-01

A Proposed Pre-Finish Cylindrical Gear Quality Standard

This proposed standard would not make any recommendations regarding the required quality for any application. The intent is to establish standard pre-finish quality classes for typical finishing operations, which only include the inspection elements that are important to properly evaluate pre-finish gear quality as it applies to the finishing operation. It would be the responsibility of the manufacturing/process engineer, quality engineer, or other responsible individual to establish the required pre-finish quality class for their application.

GEAR TALK WITH CHUCK | 2016-08-25

Gear Toys

My recent blog on educating kids on gears coincided with a birthday party invitation for a great nephew. Not having grandchildren of our own — I da...

INDUSTRY NEWS | 2016-07-20

Covering All Angles

Klingelnberg Hosts 6^th WZL Gear Conference in the USA 2016 Matthew Jaster, Senior Editor ...

GEAR TALK WITH CHUCK | 2016-06-21

Missing the Geek Squad

One of the things I miss most about full-time work is the presence of knowledgeable, in-house technical support for my comput...

INDUSTRY NEWS | 2016-03-24

KISSsoft Offers Strength Analysis for Cylindrical Gears

The strength calculation method specified in Lloyd's Register:2013 has now been implemented. This specific standard for ships is now ...

FEATURE ARTICLES | 2016-03-01

Plastic Gearing Continues Converting the Unconverted

Plastic gears are everywhere today - throughout your car, at the oceans' lowest depths, in deep space. The question, when is a metal gear a candidate for plastic conversion, can be addressed in three words, i.e. what's the application?

GEAR TALK WITH CHUCK | 2015-07-21

A Long Hot Summer

We are having a bit of a heat wave in the Chicago area, not the deadly type of 1996, but uncomfortable for much outside activity. I marvel at the t...

GEAR TALK WITH CHUCK | 2015-06-04

Things We Don’t Know

Noted gear consultant and gear educator Ray Drago is fond of saying that a consultant’s best answers usually start with “it depends.” Those of you ...

GEAR TALK WITH CHUCK | 2015-05-12

Business of Sports, Cont.

Picking up from last week on W. Edwards Deming… We’re constantly hearing sports terms and metaphors used in business c...

GEAR TALK WITH CHUCK | 2015-02-10

Uncertain Times

[starbox] While the news media is heralding improved job and income growth, people in gear manufacturing are worried about the security of their j...

GEAR TALK WITH CHUCK | 2015-01-22

Trust, but Verify

[starbox] Lest you come away from my last posting thinking I am completely trapped in the past, I’ve invested a fair amount in new software during ...

GEAR TALK WITH CHUCK | 2015-01-09

It’s All About Context

[starbox] I was one of those kids that loved reading the dictionary to learn new words, and that interest has continued into my golden years. Th...

GEAR TALK WITH CHUCK | 2014-10-23

Preserving Gear History

One of the initiatives now in progress since the close of the American Gear Manufacturers Association (AGMA) 2014 Fall FTM was building a detailed timeline of the organization’s history since its founding in 1916.

GEAR TALK WITH CHUCK | 2014-07-08

Better to be Lucky than Smart

[starbox] The special 30th Anniversary Issue of Gear Technology magazine represents a lot of extra work on the part of...

TECHNICAL ARTICLES | 2014-05-01

Application and Improvement of Face Load Factor Determination Based on AGMA 927

The face load factor is one of the most important items for a gear strength calculation. Current standards propose formulae for face load factor, but they are not always appropriate. AGMA 927 proposes a simpler and quicker algorithm that doesn't require a contact analysis calculation. This paper explains how this algorithm can be applied for gear rating procedures.

INDUSTRY NEWS | 2014-05-01

Industry News

The complete Industry News section from the May 2014 issue of Gear Technology.

GEAR TALK WITH CHUCK | 2014-04-08

A Tool Looking for a Task?

[starbox] I have been hearing a lot about 3-D printing and how it will revolutionize manufacturing in the United States. Millions are slated to ...

GEAR TALK WITH CHUCK | 2014-03-26

Where Do Allowable Stresses Come From?

One of the most important aspects of a gear rating standard is the allowable stress charts. For spur and ...

GEAR TALK WITH CHUCK | 2014-03-21

Action Items for the Gear Trade

[starbox] Recently I learned that it took over 20 years for the gear industry to agree on its first “standard” tooth form — and that was after s...

INDUSTRY NEWS | 2014-02-27

KISSsoft Offers Standards in the Shaft Strength Calculation

For an analytical strength assessement, in the first instance the currently valid standard has to be applied. Therefore, an essential tas...

GEAR TALK WITH CHUCK | 2014-02-05

Practical Magic

[starbox] Today I have t

FEATURE ARTICLES | 2013-08-01

Leading the Way in Lead Crown Correction and Inspection

Forest City Gear applies advanced gear shaping and inspection technologies to help solve difficult lead crown correction challenges half a world away. But these solutions can also benefit customers much closer to home, the company says. Here's how…

PRODUCT NEWS | 2013-01-01

Product News

The complete Product News section from the January/February 2013 issue of Gear Technology.

INDUSTRY NEWS | 2012-10-17

Okuma Presents Job Shop Productivity Open House

CNC machine tool manufacturer Okuma America Corporation and distributor Morris Midwest are hosting an event that will focus on machine to...

EVENTS | 2012-09-01

Calendar

The complete Technical Calendar from the September 2012 issue of Gear Technology.

EVENTS | 2012-05-01

Technical Calendar

The complete Technical Calendar from the May 2012 issue of Gear Technology.

FEATURE ARTICLES | 2012-01-01

New Energy - Same Challenges

Uncertainty casts a shadow over future business opportunities for manufacturers serving the new energy markets.

TECHNICAL ARTICLES | 2011-06-01

Analysis and Testing of Gears with Asymmetric Involute Tooth Form and Optimized Fillet Form for Potential Application in Helicopter Main Drives

Gears with an asymmetric involute gear tooth form were analyzed to determine their bending and contact stresses relative to symmetric involute gear tooth designs, which are representative of helicopter main-drive gears.

PRODUCT NEWS | 2010-09-01

KISSsoft Introduces New Features with Latest Release

Tooth contact under load is an important verification of the real contact conditions of a gear pair and an important add-on to the strength calculation according to standards such as ISO, AGMA or DIN. The contact analysis simulates the meshing of the two flanks over the complete meshing cycle and is therefore able to consider individual modifications on the flank at each meshing position.

PRODUCT NEWS | 2010-08-01

Heller Introduces Gear Manufacturing on Five-Axis Milling Machines

In co-operation with Voith, a major transmission manufacturer in Germany, Heller has developed a process that significantly enhances the productivity of pre-milling and gear milling operations performed on a single 5-axis machining center.

FEATURE ARTICLES | 2009-09-01

Grinding Gears for Racing Transmissions

When you push 850 horsepower and 9,000 rpm through a racing transmission, you better hope it stands up. Transmission cases and gears strewn all over the racetrack do nothing to enhance your standing, nor that of your transmission supplier.

TECHNICAL ARTICLES | 2008-03-01

Methodology for Translating Single-Tooth Bending Fatigue Data to be Comparable to Running Gear Data

A method to extrapolate running gear bending strength data from STF results for comparing bending performance of different materials and processes.

FEATURE ARTICLES | 2007-06-01

Wind Turbine Market Leads Hansen Transmissions to India

When Belgium-based Hansen Transmissions was under the ownership of Invensys plc in the late 1990s, the parent company was dropping not-so-subtle hints that the industrial gearbox manufacturer was not part of its long-term plans. Yet Hansen’s CEO Ivan Brems never dreamed that, less than a decade later, he would be working for an Indian company.

TECHNICAL ARTICLES | 2007-03-01

Effects on Rolling Contact Fatigue Performance--Part II

This is part II of a two-part paper that presents the results of extensive test programs on the RCF strength of PM steels.

TECHNICAL ARTICLES | 2007-01-01

Effects on Rolling Contact Fatigue Performance

This article summarizes results of research programs on RCF strength of wrought steels and PM steels.

TECHNICAL ARTICLES | 2007-01-01

Face Gears: Geometry and Strength

There are three distinct gear types in angle drives. The most commonly used are bevel and worm drives. Face gear drives are the third alternative.

TECHNICAL ARTICLES | 2006-07-01

Generating Interchangeable 20-Degree Spur Gear Sets with Circular Fillets to Increase Load Carrying Capacity

This article presents a new spur gear 20-degree design that works interchangeably with the standard 20-degree system and achieves increased tooth bending strength and hence load carrying capacity.

TECHNICAL ARTICLES | 2005-07-01

Systematic Investigations on the Influence of Case Depth on the Pitting and Bending Strength of Case Carburized Gears

The gear designer needs to know how to determine an appropriate case depth for a gear application in order to guarantee the required load capacity.

TECHNICAL ARTICLES | 2004-05-01

Evaluation of Bending Strength of Carburized Gears

The aim of our research is to clearly show the influence of defects on the bending fatigue strength of gear teeth. Carburized gears have many types of defects, such as non-martensitic layers, inclusions, tool marks, etc. It is well known that high strength gear teeth break from defects in their materials, so it’s important to know which defect limits the strength of a gear.

INDUSTRY NEWS | 2004-04-17

Suhner Publishes New Catalog

Suhner Manufacturing has release its new flexible shaft/bevel gear catalog, containing complete information on flexible shafts and assem...

TECHNICAL ARTICLES | 2003-05-01

Characterizaton of Retained Austenite in Case Carburized Gears and Its Influence on Fatigue Performance

Carburized helical gears with high retained austenite were tested for surface contact fatigue. The retained austenite before test was 60% and was associated with low hardness near the case's surface. However, the tested gears showed good pitting resistance, with fatigue strength greater than 1,380 MPa.

TECHNICAL ARTICLES | 2002-05-01

Carbide Hobbing Case Study

Bodine Electric Co. of Chicago, IL., has a 97-year history of fine-and medium-pitch gear manufacturing. Like anywhere else, traditions, old systems, and structures can be beneficial, but they can also become paradigms and obstacles to further improvements. We were producing a high quality product, but our goal was to become more cost effective. Carbide hobbing is seen as a technological innovation capable of enabling a dramatic, rather than an incremental, enhancement to productivity and cost savings.

TECHNICAL ARTICLES | 2001-03-01

Austempered Gears and Shafts: Tough Solutions

Austempered irons and steels offer the design engineer alternatives to conventional material/process combinations. Depending on the material and the application, austempering may provide the producers of gear and shafts with the following benefits: ease of manufacturing, increased bending and/or contact fatigue strength, better wear resistance or enhanced dampening characteristics resulting in lower noise. Austempered materials have been used to improve the performance of gears and shafts in many applications in a wide range of industries.

EVENTS | 2000-09-01

Technical Calendar

Complete Technical Calendar for September/October 2000.

REVOLUTIONS | 1999-07-01

Revolutions

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.

PUBLISHER'S PAGE | 1999-03-01

Navigating Uncharted Waters in Cyberspace

I'd like to share with you a vision of the future. It takes place in cyberspace, and it's coming soon to a computer near you. Whether you like it or not, and whether you're ready or not, the Internet is changing the way business is conducted.

TECHNICAL ARTICLES | 1998-11-01

Calculating Spur and Helical Gear Capacity with ISO 6336

This is the third article in a series exploring the new ISO 6336 gear rating standard and its methods of calculation. The opinions expressed herein are htose of the author as an individual. They do not represent the opinions of any organization of which he is a member.

TECHNICAL ARTICLES | 1998-09-01

Comparing Standards

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.

TECHNICAL ARTICLES | 1997-09-01

Structural Analysis of Asymmetrical Teeth: Reduction of Size and Weight

The present article contains a preliminary description of studies carried out by the authors with a view toward developing asymmetrical gear teeth. Then a comparison between numerous symmetrical and asymmetrical tooth stress fields under the same modular conditions follows. This leads to the formulation of a rule for similar modules governing variations of stress fields, depending on the pressure angle of the nonactive side. Finally a procedure allowing for calculations for percentage reductions of asymmetrical tooth modules with respect to corresponding symmetrical teeth, maximum ideal stress being equal, is proposed. Then the consequent reductions in size and weight of asymmetrical teeth are assessed.

INDUSTRY NEWS | 1997-07-01

M & M Precision, Penn State & NIST Team Up For Gear Metrology Research

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.

TECHNICAL ARTICLES | 1997-07-01

Structural Analysis of Teeth With Asymmetrical Profiles

This article illustrates a structural analysis of asymmetrical teeth. This study was carried out because of the impossibility of applying traditional calculations to procedures involved in the specific case. In particular, software for the automatic generation of meshes was devised because existing software does not produce results suitable for the new geometrical model required. Having carried out the structural calculations, a comparative study of the stress fields of symmetrical and asymmetrical teeth was carried out. The structural advantages of the latter type of teeth emerged.

TECHNICAL ARTICLES | 1996-11-01

The Advantages of Ion Nitriding Gears

When it comes to setting the standard for gear making, the auto industry often sets the pace. Thus when automakers went to grinding after hardening to assure precision, so did the machine shops that specialize in gearing. But in custom manufacturing of gears in small piece counts, post-heat treat grinding can grind away profits too.

TECHNICAL ARTICLES | 1995-07-01

How to Avoid Errors When Measuring Step Gears

There are problems in dimensional measurement that should be simple to solve with standard measuring procedures, but aren't. In such cases, using accepted practices may result in errors of hundreds of microns without any warning that something is wrong.

TECHNICAL ARTICLES | 1994-03-01

The Fundamentals of Gear Press Quenching

Most steel gear applications require appreciable loads to be applied that will result in high bending and compressive stresses. For the material (steel) to meet these performance criteria, the gear must be heat treated. Associated with this thermal processing is distortion. To control the distortion and achieve repeatable dimensional tolerances, the gear will be constrained during the quenching cycle of the heat treatment process. This type of fixture quenching is the function of gear quench pressing equipment.

TECHNICAL ARTICLES | 1992-11-01

Investigation of the Strength of Gear Teeth

To mechanical engineers, the strength of gear teeth is a question of constant recurrence, and although the problem to be solved is quite elementary in character, probably no other question could be raised upon which such a diversity of opinion exists, and in support of which such an array of rules and authorities might be quoted. In 1879, Mr. John H. Cooper, the author of a well-known work on "Belting," made an examination of the subject and found there were then in existence about forty-eight well-established rules for horsepower and working strength, sanctioned by some twenty-four authorities, and differing from each other in extreme causes of 500%. Since then, a number of new rules have been added, but as no rules have been given which take account of the actual tooth forms in common use, and as no attempt has been made to include in any formula the working stress on the material so that the engineer may see at once upon what assumption a given result is based, I trust I may be pardoned for suggesting that a further investigation is necessary or desirable.

FEATURE ARTICLES | 1992-11-01

1992 Marks Important Gear Design Milestone: Lewis Bending Strenth Equations Now 100 Years old

Columbus' first voyage to the Americas is not the only anniversary worthy of celebration this year. In 1892, on October 15, Wilfred Lewis gave an address to the Engineer's Club of Philadelphia, whose significance, while not as great as that of Columbus' voyage, had important results for the gearing community. In this address, Lewis first publicly outlined his formula for computing bending stress in gear teeth, a formula still in use today.

TECHNICAL ARTICLES | 1991-11-01

A Rational Procedure for Designing Minimum-Weight Gears

A simple, closed-form procedure is presented for designing minimum-weight spur and helical gearsets. The procedure includes methods for optimizing addendum modification for maximum pitting and wear resistance, bending strength, or scuffing resistance.

PUBLISHER'S PAGE | 1990-05-01

Looking To The Future

Six years ago this month, the very first issue of Gear Technology, the Journal of Gear Manufacturing, went to press. The reason for starting the publication was a straightforward one: to provide a forum for the presentation of the best technical articles on gear-related subjects from around the world. We wanted to give our readers the information they need to solve specific problems, understanding new technologies, and to be informed about the latest applications in gear design and manufacturing. The premise behind Gear Technology was also a straightforward one: the better informed our readers were about the technology, the more competitive they and their companies would be int he world gear market.

EVENTS | 1988-11-01

Technical Calendar

November 1-3. SME Gear Processing and Manufacturing Clinic, Sheraton Meridian, Indianapolis, IN. November 5-10. international Conference on Gearing, Zhengzhou, China

TECHNICAL ARTICLES | 1988-05-01

Computer-Aided Design of the Stress Analysis of an Internal Spur Gear

Although there is plenty of information and data on the determination of geometry factors and bending strength of external gear teeth, the computation methods regarding internal gear design are less accessible. most of today's designs adopt the formulas for external gears and incorporate some kind of correction factors for internal gears. However, this design method is only an approximation because of the differences between internal gears and external gears. Indeed, the tooth shape of internal gears is different from that of external gears. One has a concave curve, while the other has a convex curve.

TECHNICAL ARTICLES | 1988-01-01

The Use of Boundary Elements For The Determination of the AGMA Geometry Factor

The geometry factor, which is a fundamental part of the AGMA strength rating of gears, is currently computed using the Lewis parabola which allows computation of the Lewis form factor.(1) The geometry factor is obtained from this Lewis factor and load sharing ratio. This method, which originally required graphical construction methods and more recently has been computerized, works reasonably well for external gears with thick rims.(2-6) However, when thin rims are encountered or when evaluating the strength of internal gears, the AGMA method cannot be used.

VOICES | 1987-07-01

No Surprise

For the last few years, the market has been tough for the U.S. gear industry. That statement will cause no one any surprise. The debate is about what to do. One sure sign of this is the enormous attention Congress and the federal government are now placing on "competitiveness."

TECHNICAL ARTICLES | 1987-03-01

Influence of Geometrical Parameters on the Gear Scuffing Criterion - Part I

The load capacity rating of gears had its beginning in the 18th century at Leiden University when Prof. Pieter van Musschenbroek systematically tested the wooden teeth of windmill gears, applying the bending strength formula published by Galilei one century earlier. In the next centuries several scientists improved or extended the formula, and recently a Draft International Standard could be presented.

PUBLISHER'S PAGE | 1987-01-01

Industry Shows Shift Emphasis

A change has taken place within the industry that is going to have an enormous effect on the marketing, sales, and purchasing of gear manufacturing and related equipment. This change was the American Gear Manufacturers' Association, first biennial combination technical conference and machine tool minishow.

TECHNICAL ARTICLES | 1986-11-01

Curvic Coupling Design

Curvic Couplings were first introduced in 1942 to meet the need for permanent couplings and releasing couplings (clutches), requiring extreme accuracy and maximum load carrying capacity, together with a fast rate of production. The development of the Curvic Coupling stems directly from the manufacture of Zerol and spiral bevel gears since it is made on basically similar machines and also uses similar production methods. The Curvic Coupling can therefore lay claim to the same production advantages and high precision associated with bevel gears.

FEATURE ARTICLES | 1986-09-01

Tooth Strength Study of Spur Planet Gears

In the design of any new gear drive, the performance of previous similar designs is very carefully considered. In the course of evaluating one such new design, the authors were faced with the task of comparing it with two similar existing systems, both of which were operating quite successfully. A problem arose, however, when it was realized that the bending stress levels of the two baselines differed substantially. In order to investigate these differences and realistically compare them to the proposed new design, a three-dimensional finite-element method (FEM) approach was applied to all three gears.

VOICES | 1985-09-01

Industry Forum

Your May/June issue contains a letter from Edward Ubert of Rockwell International with some serious questions about specifying and measuring tooth thickness.

TECHNICAL ARTICLES | 1985-09-01

Single Flank Data Analysis and Interpretation

Much of the information in this article has been extracted from an AGMA Technical Paper, "What Single Flank Testing Can Do For You", presented in 1984 by the author

PUBLISHER'S PAGE | 1984-10-01

Notes from the Editor's Desk

History comes around full circle. It is interesting to talk to gear manufacturers who service the defense, aerospace, automotive and computer industries and find that their sales, production and backlogs reflect excellent and, in some cases, record breaking business.

TECHNICAL ARTICLES | 1984-10-01

Endurance Limit for Contact Stress in Gears

With the publishing of various ISO draft standards relating to gear rating procedures, there has been much discussion in technical papers concerning the various load modification factors. One of the most basic of parameters affecting the rating of gears, namely the endurance limit for either contact or bending stress, has not, however, attracted a great deal of attention.

INDUSTRY NEWS | 1984-05-01

The Process of Gear Shaving

Gear shaving is a free-cutting gear finishing operation which removes small amounts of metal from the working surfaces of the gear teeth. Its purpose is to correct errors in index, helical angle, tooth profile and eccentricity.