Even in this tough economic environment opportunity continues to knock on the doors of companies like Schafer Gear Works Rockford LLC. This division of the company, which is headquartered in South Bend, Indiana, has both the expertise and the willingness to take on the production challenges of large, custom, and very high precision spur and helical gears, both external and internal. As a result customers are some of the world’s biggest names in agriculture, construction, and mining equipment—and among the most demanding, particularly where quality and delivery are concerned.
Solving the Inspection Challenge
With its larger gear business in full swing and the shop running two shifts a day, five days a week, Schafer Gear Works’ most recent investment in expanding its capacities—including 800mm turning, 900mm hobbing, and 800mm profile grinding—is paying off, with the pipeline full and flowing smoothly. But it has also put increasing pressure on an older gear inspection system that has struggled to keep up with demand, according to Carl Wedig, manufacturing engineer manager. “Meeting the rigorous inspection requirements of these larger gears, many with accuracy requirements as high as AGMA 14, was becoming increasingly difficult, if not altogether impossible, with our circa 1995 gear inspection system,” he says. “It also lacked the capacity to handle gears upwards of 1 meter in diameter, a size range that is becoming a larger percentage of our business day to day. Gears of that size would have to be outsourced for inspection.”
Help came in the form of a new Gleason 1000GMM analytical gear inspection system, which almost literally hit the ground running just weeks after Wedig and his team began their search for a new metrology solution. “We were charting parts just four days after delivery,” he says, “a testament not only to Gleason’s excellent installation and training, but also to how easy it is to bring operators up to speed on the Gleason system.”
Cutting Inspection Time in Half
Wedig says the new Gleason 1000GMM has brought a level of performance and big gear capacity to Schafer that enables the company to now meet all its inspection requirements in-house for gears as large as 1000mm in diameter and 1300mm in length. The Gleason GMM, as compared to other inspection systems in its class, is also particularly robust, making it well suited for Schafer’s typically large and heavy workpieces. The GMM’s solid granite base, Meehanite® cast-iron slide assemblies, and heavy duty rotary table with 985mm diameter table top give it exceptional stiffness and rigidity, accommodating gears weighing as much as 2200kg. But what really stands out for both he and his operators is its ease of programming, which Wedig claims cuts the inspection time normally required for a new gear in half. “This is an enormous benefit to us since, in the interest of efficiency, we require that our machine operators also use the inspection system to perform all the measurements on a finished part,” he explains. “Where programming for first or ‘one off’ parts might have taken 20 or more minutes on the older inspection system, we now can do it in under 10 minutes on the Gleason GMM. It’s just so much more user-friendly and powerful.”
What Wedig is referring to is Gleason’s new GAMAtm (Gleason Automated Measurement and Analysis) operating software, a Windows-based application that puts a host of features right at the fingertips of the operator in a simple, highly intuitive graphical user interface (GUI). Here’s how it makes life easy for Schafer’s operators:
• A typical screen has “quick buttons” across the top, giving the operator immediate access to the most common system operations (see Figure 1). All important gear and specific test information is shown down the left side of the screen, with tabs and forms making it easy for the operator to quickly and accurately establish gear parameters. The majority of the screen is used to chart the inspection results of, say, lead and involute tests, which appear in real time as the tests are performed. There is also a status bar at the bottom of the screen detailing the stage of the operation, who is operating the system, part number, and so on.
• Operators start the process by either recalling, loading, and activating existing part programs with the click of a mouse, or by creating a completely new part program, which can be done in just minutes in a few easy steps. The operator simply selects from a list of typical machine configurations, enters a part number, and clicks a “create” button. A series of tabs then appears across the top of the screen (Figure 2). The operator clicks on these tabs one by one, filling out the necessary fields with pertinent gear data, special tests required for highly modified gear profiles and geometry, the type of analysis required—GAMA supports all global industrial standards such as DIN, AGMA, ISO, JIS, etc.—and so on. The operator also can select a variety of options for how a permanent record of the inspection is stored, whether in PDF format, SVG (Scalable Vector Graphics), or even HTML for easy e-mailing.
In addition, GAMA is a true Windows VB.NET application, making it fully compatible with the latest LAN and WAN networks, so that users can easily interface inspection results with their gear design and production resources for corrective actions downstream.
New Probe Makes Better “Sense”
The Gleason 1000GMM is just one of a new-generation GMM family ranging in size from 350mm capacity all the way up to a 3000mm capacity. Among the most important characteristics of the new design is their use of a series of Renishaw SP80H 3-D scanning probes, with various stylus sizes and configurations, including 500mm long styli to reach deep into internal gears and all interchangeable from an automatic probe changer. Figure 3Wedig says that the Renishaw probe provides a high speed, high accuracy measurement capability vastly superior to the 2D probe system used by the older system. “The old probe system can gather information only at discrete points up and down or side to side on the X and Y axes, while the new GMM has a true scanning probe that acquires much more data faster by traveling along the surface of the part in all three dimensions—up, down, side to side, and in and out,” he says. “It gives us a level of inspection that you would normally associate with a CMM in a quality lab.” Figure 4
Wedig says that he couldn’t be happier with the results to date. In fact, he’s already looking downstream, with the company making plans to market yet another Schafer Gear Works capability: “inspection only” work. “Fast, accurate, and economical inspection of larger parts is something we can now offer customers who don’t have that capability in-house,” he says. “We expect the Gleason GMM will be very busy in the coming months.”