What is a Military Tracked Vehicle Manufacturer
Comprehensive SPC Program Gives Company Competitive Edge in Shrinking Market
A world-leading manufacturer produces military tracked vehicles that support U.S. defense needs and the armed forces of more than 20 international allies.
The United States and other countries have less money to spend on new equipment. As budgets have shrunk, orders for new equipment have been reduced, and there has been a fierce increase in worldwide competition for new vehicle orders.
To counter reduced military budgets, the manufacturer wanted to find effective and innovative ways to remain competitive. To help maintain its share of market, the company decided to implement a comprehensive SPC program, supported by DataMyte data collection systems. The manufacturer hoped implementation would help to continuously improve product quality and reduce costs and time to market.
The company had been charting data manually and, when a problem occurred, quality engineers would pull file folders on cabs produced over the previous three or four months to generate X-bar and R charts and histograms. The manufacturer found that this system wasn’t very effective. The data was usually too late to be of value.
If a family cab left the machining area for assembly, it created a rework situation that slowed down the line. If inplace repairs couldn’t be made, the components were subjected to a material review board–a time-consuming and expensive process. If the part could not be brought to within specifications, it was scrapped.
The company decided to initiate a comprehensive automated DataMyte SPC program data collection system in its machine cabs and hulls production area. The cabs, which measure about 15-feet on a side, have some 600 features to be machined to tight tolerances. The machining process is complex, and operations must be accurate and precise if the cab is to meet engineering specifications.
The company installed DataMyte 953 data collectors on its two, large horizontal boring machines: a Gray and a Giddings & Lewis. Operators were trained to use gages for setups, proofing, and checking of upper and lower control limits. The data was then transmitted by radio frequency (RF) to the data collectors, which compiled it and charted results on terminals at the machining centers. The data was maintained by the quality engineering department in a computer that was accessible to other quality engineers, production and design engineers, and management.
Because many of the manufacturer’s products are large and difficult to measure with a micrometer, the company used a laser-tracking system. Operators moved a target from point to point, much like a mobile ruler. The laser tracked and calculated the dimension, which was recorded and compared with specifications in a computer.
The company wanted to use the data to improve process capabilities. Quality engineering copied the data to a disk and transferred it to a personal computer running Datamyte’s TurboSPC software. That information was incorporated with other manufacturing data to give quality, production, and design engineers and managers a real-time overview of the manufacturing processes.
The new SPC, with the Datamyte data collection system, made it possible for the manufacturer to effectively certify its manufacturing processes and improve machine tool capability. Unplanned downtime has been reduced by 50 percent. Scheduled maintenance hours have been cut by 30 percent. Machining cycle times have been reduced 50 percent, while product moves have been reduced 30 percent. Inspection cycle times have been cut by 95 percent. Fewer products are sampled, but with greater confidence. And design engineers have access to machine capability information and can design products that can be produced with greater cost efficiency and quality.
Equally important, quality information is immediately available to U.S. government representatives at the plant. The onsite government inspection and contract management office can now get all the information it needs and have it on-line and on time.
The most notable result has been the improvement in product quality. For the first time in the company’s history, it can look at its data and have confidence that the plant has a good process and a good product. Since implementing the automated SPC system, the manufacturer has machined more than 180,000 features of size on more than 300 cabs without a material review board.
Payback for the Datamyte data collectors has been short, and the manufacturer now plans to create a network of Datamyte data collectors throughout its facilities. The expanded system will use Datamyte’s Quantum SPC software, which will improve access to information for everyone concerned with SPC.