Measuring Roughness and Surface Finish in Gears...

(Image Source: vibanalysis.co.uk)

If, like me, you read Gear Solutions magazine regularly, then you probably have read the "Tooth Tips" section before, and are probably aware of how smart of a guy William Crosher is. The reason I like his articles is because he doesn't dumb down the language for non-engineers. If you want to follow his articles, you have to be part of the industry, and that's just fine by me. The recent issue of Gear Solutions' "Tooth Tips" article is about the importance of roughness and surface finish as they relate to the longevity and effectiveness of a gear assembly. Without getting into great detail (he does, you can read the article if you want to get the full scoop), his basic point, in his own words, is as follows:

"There is no relationship between gear quality and surface finish in AGMA standards. An AGMA document on gear tooth surface texture (AGMA906A94) is a guide to surface finish. Unfortunately, there are still many who do not realize the significance of the surface finish on tooth flanks and believe -quite incorrectly- that it will be a self-correcting condition. Tests have indicated that the rubbing of any two surfaces reduces the initial roughness by no more than 25 percent."

Another point Crosher makes is that in order to achieve more accurate results, one must be aware of the "cutoff". There are several types of gears that have surfaces with many deep valleys, and its important to remember that flank surfaces should be measured in one direction, going from the tip to the root. Crosher's article is important because it discusses the need for standardization of further processes by AGMA while giving logical assessments of the importance of measuring roughness and surface finish. I always like an article that can make a process more efficient - they always end up saving me money.

To read Crosher's article, click here:

http://gearsolutions.com/article/detail/6001/title/william-crosher-tooth-tips

To find out more about recent developments in gear manufacturing technology, check out Gear Motions:

http://www.gearmotions.com/capabilities/ground-gears.php

Turning Bearing Failure into Bearing Success

(Image courtesy of toyotaoffroad.com)

There's an interesting article in Gear Solutions magazine this month regarding the identification and analysis of failed bearings. The article discusses how important it is for engineers to dissect bearings that have failed prematurely on a visual level, as well as taking the time to fix the causes of the failure as opposed to trying to re-invent their whole process. It is common in the gear industry for someone to say "Well, this bearing arrangement didn't withstand the amount of stress it was supposed to, we either need to implement a new set-up or at least the same process with a new material." The article discusses the problems and causes thusly:

"Most bearing failures such as flaking and pitting, spalling unusual wear patterns, rust and corrosion, creeping, skewing and others are usually attributed to a relatively small group of causes that are often inter-related and correctable. These causes include lubrication, mounting, operational stress, bearing selection, and environmental influence."

The article then gives a breakdown of the likelihood of each of the causes of bearing failure. Lubrication issues, including unsuitable, insufficient or aged lubricant, total fifty-five percent of bearing failures. Around thirty percent of failures were attributed to solid and liquid contamination, leaving only fifteen percent for errors such as "wrong bearing chosen" or "errors while mounting". Using these statistics, one can see that the majority of bearing failures are the result of miscalculations regarding lubrication, whereas only 1/3 of failures are due to standard wear and tear, and less than 1/5 of failures are the result of incorrect bearing selection or implementation. Keep these figures in mind the next time one of your bearings fails, you might save yourself some money by fixing something as simple as lubricant distribution, rather than replacing an entire arrangement.

To read the article from Gear Solutions magazine, you can download the entire issue from the link below:

http://gearsolutions.com/magazine/currentIssue

Gear Expo 2011 - Why You Should Go

The Duke Energy Center, home to this years Gear Expo

Every year, manufacturers and engineers from all across our industry get together to discuss the latest trends, technologies and strategies that are helping the evolution of the gear industry. The expo will run from November 1st to the 3rd at the Duke Energy Center in Cincinatti, Ohio. While registration for exhibitors and attendees are currently restricted, it is of interest that the website of the expo went live last week at www.gearexpo.com.

The article lists several powerful reasons for attending, the most notable being:

1. Make a more educated purchasing decision - Your sales reps can't travel around the country with their heavy machinery, so Gear Expo is your best opportunity to see the equipment in person before you make a large acquisition. You'll easily make up the time out of the office by holding a year's worth of business meetings in just three short days.

2. Stay ahead of the business cycle - Gear Expo only happens once every two years, you can't afford to miss it or you will be left behind as the industry moves forward.

3. Take a trip around the world of gearing all under one roof - Exhibitors and attendees travel from 30 countries and 30 states to meet at Gear Expo. Hear what's working across town or around the globe, and learn from your peers who stand in your shoes everyday.

4. Get out of your office or plant and discover your next "big idea" - Engineers, managers, and executives often spend too much time in an office. Don't miss the innovation that will drive your company and careers forward.

This list from the website covers the main reasons you'd want to go, but it does omit one large important benefit of attendance: Networking. The connections you make at an expo like Gear Expo 2011 can help propel your business to the front of the line in the gear manufacturing game. By establishing relationships with others in your field, you can decrease your own costs, find opportunities to work in tandem with other manufacturers and improve the overall efficiency of not only your institution, but the industry as a whole. So, plan to take the first three days of November off and come down to Gear Expo 2011!

New Combined Process Machine out of Rochester, NY

Image courtesy of Gleason.com

A new combined process machine by Gleason is setting the standard for multiple-function machines for gear manufacturers that require drilling, milling, chamfering/deburring, hobbing and turning all in a single operation. As modern gear manufacturers are aware, the industry is propelled forward by developing more intricate and complex gear designs that can handle larger loads with increased durability and efficiency. A machine like the AGILUS® 180TH represents the next generation of gear-manufacturing hardware, allowing several tasks to be completed in unison, saving the user time and resources.

An article on the new machine by Thomasnet News says of the AGILUS 180TH:

"As compared to typical production of cylindrical gears requiring hobbing, the AGILUS 180TH greatly reduces the number of machines, setups and overall through-put times for the complete processing of the gear, thus reducing both the capital investment and cost per workpiece for the user. AGILUS' ability to perform, in a single setup, complete machining of a wide range of shaft- and disc-type cylindrical gears also gives the user a greater degree of flexibility, higher machine availability, and optimized throughput as compared to the typical process where multiple single-purpose machines are used, requiring time-consuming changeover from part to part."

As the gear manufacturing industry continues to evolve, it is likely that machines with similar capabilities to the 180TH will continue to drive the evolution of the gear market. As lower batch sizes, increasingly complex gear applications and reduced inessential setup times become issues that relate to a business' bottom line, more gear manufacturers will be drawn to do-all machines like the AGILUS 180TH. In the next few years, these machines will continue to be instrumental in the development of our industry, meaning more jobs for qualified operators, less money wasted on inefficient operations and more options for gear manufacturers and their clients.

To read the article from Thomasnet News, click the link:

http://news.thomasnet.com/fullstory/Multifunction-System-offers-complete-cylindrical-gear-machining-574577

For more information on complex gear-machining processes, check out Gear Motions:

http://www.gearmotions.com/gearing-news/