Automated cells transport shop into 21st century machining.
By Patricia L. Smith
The Acela locomotive sports components machined by Eagle Bridge Machine & Tool.
(Photo courtesy of Amtrak)
EBM's Toyoda cell eats up work, so the company has to have parts such as these disk brakes ready and near the machines.
EBM uses the Toyoda cell, which features two FA630 HMCs, to machine cast iron disk-brake castings. Compared to the previous method of machining, the cell slashed cycle time by more than 50%.
Toyoda and Kennametal have helped EBM match its tooling to the horsepower of its machines.
EBM specializes in machining train components such as this high-alloy steel casting (top) and this low-alloy steel casting. Both parts are produced on EBM's original Toyoda cell, which sports two FA550s.
In three short years, Eagle Bridge Machine & Tool Inc. (EBM) has transitioned from a 60-man jobshop running three manned shifts to a 30-man jobshop running one manned shift and one completely unmanned. The company has also gone from 23 machine tools to 12. At the same time, it has increased capacity 40% and locked in a six-year contract to make train parts for its largest customer. According to Robert Farrara, EBM's president, moving from circa-1984 vertical and horizontal machining centers and lathes to fully automated cells has allowed the company to survive — and even thrive — in today's rough economic climate.
"We wouldn't be here today without these machines," he asserts. Farrara refers to the company's two automated CNC systems, manufactured by Toyoda Machinery USA, Arlington Heights, Ill. Each of these cells sports two horizontal machining centers (the original cell has two FA550s; the newest has two FA630s), a rail-guided-vehicle system, and the Mach III/System 2 cell controller. The company also has a standalone FA630, which was originally added for development work.
However, this machine is usually swamped with production jobs. These machines have the flexibility to deal with EBM's main work — machining castings for mass transit and heavy machinery. Among the parts EBM makes are components for commuter railroad cars for the New York Metropolitan Transportation Authority, Long Island Railroad, and Metro North Railroad. It also machines parts for Amtrak's Acela high-speed rail cars.
The shop, which is located in Eagle Bridge, N.Y., has seen its customer base shift greatly over the years. Once a planned producer for the U.S. government, EBM also served the automotive sector, making aftermarket parts such as alternators and starters. But in recent years, this customer base has eroded as the work moved offshore to China. EBM, however, predicted these changes and positioned itself to tackle a huge contract with the mass-transit industry. "Trains are a niche business, and we have a reputation for tackling complicated castings," says Farrara. EBM machines 23 castings for an order of 1,100 railroad cars over a sixyeartimeframe. "The car builder is shipping one car a day. If we're late with one casting, that's $1.8 million it's not shipping." To win the contract, Farrara made a commitment to his customer. "I told them I would invest in the equipment so that I could deliver the parts," he relates. "It's quite an undertaking for a shop to make this kind of an investment in one customer. But I've worked with these people for 20 years, and they know that I say what I mean and mean what I say."
Farrara was convinced that automatic cells were the way to go, but he had to overcome sticker shock at first. "Then I remembered having to convince my father to buy our first CNC machine," he recalls. The machine cost about as much as the building it was housed in, he laughs, but it was critical to EBM's later success.
He knew that the automated cells were just as necessary, although the initial investment was daunting. But he immediately saw a return on investment once the cell was installed and running. "These machines have so many benefits," he says, "including much more capacity." The cell also slashed cycle times as much as 50%. The installation was so successful, in fact, that within two years, EBM added the second cell and the standalone FA630.
New methods of machining
Moving to the Toyoda cells quickly changed how EBM approaches its work. In one of the best examples of how its altered its machining routines, EBM moved from running a disk brake for a train on a manual lathe to the Toyoda cells. The parts, which weigh 900 lb, are complex and require a 1,500-lb fixture to hold them.
EBM reports that setups were a pain on the lathes. The only way to fixture the part was to use a special wedgetype system. The job ran in 45 min — 15 min of which involved setup.
Today, the job runs in 22 min, which includes a 2-min setup using a probe. As Farrara explains, "The machine probe picks up the centerline between the fins on this part. Previously, we had to use a special fixture that allowed us to come in and locate off those fins. But now, we probe the inside of the casting, determine where the centerline is in relation to the casting, and turn the part around to do the same thing on the diameter of the other side. We probe that so our wall thickness will be the same, which is critical."
Tony Farrara, EBM production manager elaborates: "Our customer wants two surfaces with close toleranceon both thickness and symmetry.-Instead of using fixturing to locate,-we use the probe to establish the part is on-center and where to machine. When we check our results, surfaces run nominal time and time again. Our operators simply load the parts and setup is complete."
The cells let EBM work quickly and efficiently to gain a leg up on the competition. As Tony puts it, "We could have continued to do everything on the old machines, but we probably would have lost our customer. Instead of, say, $100/part, it would have been $170/part to produce because of the inefficiencies," he comments.
Another huge change for EBM was moving to an unmanned shift at night. EBM's first cell runs 14 or 15 hours a day — about six hours unattended. Depending on the production schedule, the second cell may only run two or three hours unattended. But the upshot is that operators load the cells, start a program, and go home. The machines are all wired for automatic coolant fill and automatic shutoff. An auto dialer is also wired in to alert an offsite location if any problems arise.
Going lights-out was strange, as Tony recollects. "As we walked to the door that first night, all was dark, and you could hear the cell running. We came back and stood by it for a while. We knew we had to go sometime, but it didn't seem right — we were all used to standing by our machines, listening to them running." He admits, though, that their concerns have faded as the Toyodas continue to produce without any major problems. Now, they leave at the end of the day without hesitation.
Scheduling and setup
In addition to the unmanned shifts, EBM also changed its approach to setups and scheduling. "Previously, I kept track of 12 machines, 12 sets of tooling, and 12 setups," says Tony. "There were only two of us who did setups, so we programmed and set up jobs during the day and came back at night to do more. Now, switching from one part to another is a matter of telling the operator to 'Run 10 of these today.' I might not even check back."
EBM schedules as tightly as possible to maximize the cells' capabilities. "We have multiple jobs set up on several tombstones," remarks Farrara. "On one side of a pallet, we might be machining the base and drilling holes. On another side, we're turning and boring. An operator might run these together during the day and a load of each unmanned at night. We schedule everything by how many parts we need a day. And these machines have tremendous ability for scheduling."
Tony adds that the machines are work hogs, so it's important to keep work in front of them. "For that, we have to schedule tightly," he says. " There's an upside and a downside to doing that. As long as you have work and the customer doesn't call up and ask for double what you've scheduled, you run your parts through — perhaps four during the day and two at night. But if you get a casting late, then you have to run strictly that casting and pound it out. You have to have everything in line to keep the flow. I don't care if you have six machines or just one machine with six pallets — it's the same theory."
Freeing up other resources
The cells have freed up more than machine time; they've also freed up operators and the two setup people. They can now do preventive maintenance and investigate new technologiesto further improve production.
"Our operators now have the time to review whether or not we need new tools or fixtures — anything that shaves minutes off the run time," comments Tony. "We're constantly on the lookout for new technologies. This new technology and development has enabled us to do cost reduction for our customers as well as continue to maintain our profit margins. A win-win situation."
For example, the company is working with Kennametal Inc., Latrobe, Pa., on tooling. "Our Kennametal representative, Mike Schulte, is doing development work here, helping us find cutters that match the Toyodas' capabilities and horsepower," explains Farrara. "We're using every aspect of these machines — all the capacity, four-sided tombstones, and through-the-spindle coolant. We're doing heavy and light milling, drilling, and boring."
Other improvements that EBM has implemented over the past few years include a tool-storage system that is 21/2 stories high. Farrara says it's one of the best investments he's made. "Instead of having tooling cabinets all over, everything is maintained in one place." He's also made a nice profit off a chip briquetter. "Rather than having someone haul away four dumpsters of chips every day, someone pays us for the chips." Another improvement involves a chip fan that blows chips off parts. According to Farrara, the fan goes right into the Toyoda machine and was well worth the $50 investment.
EBM has also upgraded both cells since their initial installation, further expanding the company's capabilities and competitiveness. The FA550 system, which was originally a one-machine, 12-pallet system with two load stations, has expanded to two FA550s and 18 pallets. The cell could also accommodate a third machine at a later date.
EBM may also add a couple of pallets to this cell. "All we need is more cage and more track, and a few tweaks to the software," remarks Tony. He adds that they are considering upping the toolchanger from 60 to 120 tools. " Currently, we have limits to the number of jobs we can run," he says. "Say we run a different job on each side of a tombstone. If each side requires 10 tools, that's 40 tools for one pallet. And we still have other pallets to process." A larger toolchanger would eliminate these problems.
Recently, EBM upgraded its FA630 cell, which started as a onemachine, eight-pallet system with a single load station. The company added another FA630 and eight pallets, creating a cell consisting of two machines, 16 pallet buffers, and a second load station.
According to Farrara, all these changes have been an investment in the future of EBM, and he's willing to invest where it's warranted. "I look at it this way — next year, I'll be getting more sales because I'm more competitive. We go up every avenue to maintain our costs. We won't raise our prices based on inefficiencies."
Cell controller makes scheduling simple
The user interface relies on an easy-to-use graphic layout special to each cell. Users click on any machine icon to check job instructions, reports, offsets, tool-magazine configuration, and program management. Production data, operation, and alarm logs are stored in a Microsoft Access database, allowing for both daily reports and longterm capacity utilization.
"This system gives us all sorts of data as far as run times and scheduling," explains EBM's Tony Farrara. "We can call up unmanned time to see how long it ran at night. We can tell it what side of a tombstone to run and what program runs on what side of the tombstone."
William Vejnovic, vice president of engineering for Toyoda's Cutting Machine Division, says that the layout of the system allows shops to call up information across the whole system or by individual pieces of equipment. "If I move to the top menu, I can get a production report for the complete system. For individual machine results, I click on that machine. If I park the cursor over a pallet, an information box pops open and tells me what part number is on the pallet and what type of work is set up."
Farrara confirms that using the system is simple. "Everything is controlled by one PC, and everything is drawn out — the screen shows our machine, the two pallets within the machine, the changing area, and the RGV. If we want to bring a different pallet into the machine, we drag and drop it. The system automatically brings it up in the schedule."
The Level 2 software that EBM is running takes information about components and fixturing and performs offsets. "With the Level 2 system, every part, subplate, and tombstone has some offset signature," explains Vejnovic. "When a shop makes attachments to those components, the offsets are sent to the machine tool."
Vejnovic says that once a schedule is set and jobs are prioritized, pallets are presented in the order a shop wants them to run, based on the production schedule. If a new job comes in, it's a simple matter to add it to the schedule without interrupting production.
It's also easy to check jobs from locations away from the machines. At EBM, for example, the controller is networked in with the rest of the facility. "This allows our PC to be backed up every night on our main server," says Farrara. "In addition, our programmer works in the shop, but he has a PC at home, where he can dial into the office computer, jump onto the network, and see what these machines are doing." If a problem crops up that EBM can't fix, Toyoda has the capability to perform remote diagnostics.