Cincinnati--When you run a job shop that produces numerous high-volume parts, keeping costs under control can mean bigger profits. That's exactly what American Micro Products Inc. did by switching to a new stainless steel alloy to make these complex components.
How much did the company gain by making the switch? Check out these numbers: up to 40% increase in manufacturing throughput, a 50% reduction in cycle time, and longer tool life.
American Micro had used Project 70(reg) stainless steels Type 303 and 304 supplied by Carpenter Technology Corp. (Reading, PA). Management found, however, that conditions seemed right to capitalize on the reported advantages offered by Carpenter's new Project 7000(reg) stainless steel series.
The shop runs large volumes of small-diameter stock, producing up to a half million each of several parts. Since the high-technology plant routinely tracks costs, it found that it had machines that could run at higher speeds. It based its finding on the fact that the fairly complex parts were short enough to keep material weight low.
Jinggle pins used in the thermostats of diesel engines provided a good test case for the new stainless. The pins vary slightly in size and complexity and are turned on a single-spindle Swiss automatic screw machine. A typical pin, with a spherical ball on the end, measures 0.188 inch in diameter and 0.500 to 0.750 inch long. The shop makes about 250,000 of these pins per year.
With the switch to the Project 7000 stainless grade, the shop halved its cycle time from 56 to 28 sec per part. It estimates that pin throughput has increased from 25 to 40%, depending on the part's configuration.
Use of the new stainless offered American Micro another benefit. Before making the material upgrade, the shop had to sharpen its tools three to four times per shift. With the Project 7000 Type 304 stainless, tools need sharpening only twice a week. This translates to 7 to 10 times longer tool life.
American Micro experienced similar benefits in the manufacture of small cylinders for miniature pneumatic valves, as well as for diesel-engine buttons.
"We have used the Project 7000 stainless steels on a lot of shorter runs of 5,000 to 10,000 parts," notes Gary Heineman, American Micro sales manager, "and have seen a typical increase of 30% in throughput. In general, we find that the more complex the part, the more machining is required, and the greater the benefits offered by the new grades of stainless steel."