American’s vertical integration means that 100 percent of the work is done in-shop: engineering, repair, alodine finishing, mounting, and brake relining. Doing everything in-house reduces cycle time, saves shipping costs, and reduces inventory.
No longer is every wheel stripped of paint. “We don’t just paint wheels for the heck of it,” says Carl Black, Wheel & Brake Center supervisor. Stripping takes time, and so does painting, which also adds weight. Inspection cycles are so short (even “total rebuilds” take place each 18 months) that corrosion rarely takes hold — the alodine coating does a sufficient job of adequate protection. “We don’t remove intact paint unless absolutely necessary for inspection,” he says, “and putting on new paint every time would serve no practical purpose.”
Brakes and critical steps
However, every overhauled brake does get relined. In fact each steel brake contains approximately 140 of pads on five stators in assembly with four rotors, a pressure plate, and torque tube at an estimated overhaul cost of around $10,000 per brake. In comparison, a carbon brake (where each stator and rotor is individually machined from a carbon disc) can carry a full-stack cost of up to $50,000; they’re used in certain applications where the significant weight reduction and increased service life produce cost-justifiable long-range efficiencies.
Some critical steps of assembly are automated, and the precision of the automation prolongs the service life of components. For instance, the auto-torque that reunites wheel halves holds +/-2 percent torque tolerance, better than the 4 pecent a worker achieves manually with a torque wrench. There is plenty of manual labor in the tire inflation cages (nitrogen only), and in the soap-check for leaks. The visual soap-check is extremely effective when performed by the right people; Black estimates that this improved method alone saves a day of turnaround, and commensurate inventory and floor space.
In most cases, the common hardware, things like the bolts and nuts that hold the wheels together, are re-used. Because all the assembly and disassembly is performed using dedicated tools that fit the parts and automatically and precisely achieve the proper torques, hardware lasts a long time, though visual inspection is performed at several stages: disassembly, cleaning, and reassembly.
Tires, as mentioned earlier, often go through more than one trip to the Tulsa facility. The old adage of the squawk, “Right inside main tire almost needs replacement” followed by the log entry, “Almost replaced right inside main tire” reflects business sense and a lot of common sense, and American’s people in Tulsa like common sense.
With this much volume, the Wheel & Brake facility sends a full truck to Dallas (DFW) and Chicago (ORD) each day; other locations are served by FedEx, except for some urgent AOG situations, when wheels and brakes are sometimes shipped as cargo in American’s fleet.
The overall impression one gets when walking in the huge doors is one of organized, 19th century factory labor. However, as one gets close to each station, the care for both employees’ backs and the environment is crystal clear. The pre-wash, the all-water cleanings, the re-use of water — all these belie an undercurrent of care for those who are downstream, both literally and figuratively. The attention is there for the regulations, of course; but the impression is that the Wheel & Brake facility does these things because they’re the sensible things to do. The ultimate result is greater cleanliness and greater resource savings, plus occasionally having a jump on new regulations.
Management is on the floor much of the time, keeping an eye on workflow and looking for — and listening for — improvements, which are frequently offered, examined, discussed … and implemented.
Beyond this, each stage is optimized for efficiency, minimum movement of parts, trackability, and balance with the rest of the system. A shop of this size is a giant machine itself, and each component both depends on and supports other components. Cross-training goes a long way toward continuing efficiency, as one operation can get help from another to keep work steadily moving. Another advantage is that each worker has an appreciation for every other worker, and thus can work to make everyone’s jobs easier, smoother, and safer — and when these giant parts are moving through the building at a fair clip, safety is on everyone’s mind, as is the ultimate use to which these critical parts are put.
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