Departments - Features
Gear Manufacturer Works with Tooling Supplier to Cut Costs
3/16/2010
Brad Foote Gear Works successfully eliminates troublesome bottlenecks.
The economy of the past year has proved incredibly challenging for most American manufacturers. As markets have shrunk and demand has dropped, many shops have struggled to improve efficiency and achieve savings that can keep them profitable. For a producer of gear components located in Cicero, IL, significant cost savings were achieved by working with Sandvik Coromant to eliminate a troublesome bottleneck.
Brad Foote Gear Works has a long history of providing customized precision gear products to a variety of industries. Celebrating its 85th anniversary, the company has maintained its position as a market leader by working closely with customers and delivering consistently high quality in its products. The company was the first gear manufacturer in the United States to receive ISO 9001 certification, and constant improvement in every aspect of its operations plays a vital role in Brad Foote’s success.
By integrating Sandvik Coromant tooling to eliminate a manual grinding process, Brad Foote Gear Works achieved $214,465 in annual savings.In recent years, Brad Foote has become heavily focused in the energy industry. The company specializes in gear boxes that transform high rotational speeds with little power into slower speeds with high torque. Brad Foote gear boxes can be found in a wide array of drilling operations for oil and natural gas, as well as wind energy applications where large turbines are used to generate electricity.
Tom Eul joined the team at Brad Foote in 2004. At the time, he had close to 20 years of experience as a machine operator and was hired to apply his expertise to supervision of the turning department. Success in that position led the company to promote Eul to the engineering department, where he acts as the primary programmer for all of the company’s CNC machines. In early 2009, he began to conduct an evaluation of the plethora of operations being performed on the facility’s floor. One job in particular captured his attention.
“When I was walking through the shop, I came to a work station with considerable backlog,” Eul says. “The part in question was a 66" diameter gear that was 16" wide. When parts that size start backing up, it can really create workflow issues, so we decided to focus some attention on that station.”
The gear at issue was machined from hardened 4340 steel for a customer in the wind energy sector. It contained 87 large internal teeth that were cut on an internal gasher. Due to the angle of the cut, the gashing cutter would kick up a large, heavy burr upon entry and exit from the part. The station suffering from the backlog manually deburred the component and introduced a 0.25" chamfer to the tooth edges. Investigation revealed that the operation had a troubled history.
Using a 5" handheld grinding wheel, an operator would manually remove each burr from one of the large gears. The most obvious issue with the station was that it required a process time of 5 hours per gear, introducing a significant bottleneck into the manufacturing process. Consistency in quality also proved challenging. Tolerances of 0.0002" had to be held on the teeth and very slight deviations in the chamfer could result in parts being sent back to the station for rework.
“The manual grinding was having a substantial impact on our process flow, but it also was an unpleasant job for the operator,” Eul says. “First of all, there are sparks flying everywhere and that is always a less than ideal work environment. We also had experienced multiple instances of the grinding wheel shattering while it was in use. When that happens to a piece moving at 30,000rpm, people can get hurt. We have had two operators require stitches in their arms after grinding wheels they were using shattered.”
Eul’s experience in CNC machining led him to believe that the chamfering could be completed on a milling center, after the teeth had been cut on an internal gasher. To investigate potential solutions, he called Arlen Anderson, a local Sandvik Coromant representative that had helped integrate tooling solutions into other areas of the facility. In April 2009, the two men spent an afternoon reviewing the job.
“We identified several possible solutions and then settled on a T-Max indexable chamfering tool,” Anderson says. “Given the accuracy requirements and material being worked with, the T-Max would offer the best combination of cutting speed, reliability, and tool life.”
Two days later, Anderson returned to Brad Foote with the tools. He worked with Eul to finalize the new cutting program and the first test cut was performed. The cutting data was then refined, arriving at final parameters of 3,000rpm cutting speed with a 24ipm feedrate. Process time for deburring and chamfering dropped to just 40 minutes per component, representing a reduction of nearly 87%. Tool life was strong as well, with the tool handling all of the teeth for three gears before an insert change was required.
In addition to substantial productivity gains, use of the T-Max dramatically improved quality by offering a more consistent performance. Part rework due to the operation was eliminated. Furthermore, operator safety was much improved.
“We obviously eliminated the chances of an operator being hurt during the manual grinding operation,” Eul states. “We also reduced the risks of injury during part handling. When the gears come out of the gasher with large burrs, there are lots of sharp edges and it can be very easy to accidentally cut yourself. Now, we just put it in the milling center afterwards and it is coming out with edges that you can run your hand over without hurting yourself.”
To determine the total cost savings of the new process, Brad Foote and Sandvik Coromant estimated total process time under the old and new methods. On average, 22 of the gears were produced per week and moving from a manual to automated process eliminated 5,347 hours of production time. Total annual cost savings came out to be $214,465.
“It has been a tough year for all American manufacturers, but the energy industry has been hit especially hard,” Eul says. “When oil prices peaked in 2008, there was a huge push for alternative energy that really propelled us forward. The following contraction has been tough to weather and our operations have shrunk while we wait for demand to pick back up. Being able to eliminate costs is always a good thing, but it is especially vital in times likes these. It is good to know that we have a supplier like Sandvik Coromant that can help support the expertise we need to streamline our operations.”
Sandvik Coromant
Fair Lawn, NJ
coromant.sandvik.com
Brad Foote Gear Works
Cicero, IL
bradfoote.com