Nongalling stainless steel a fitting choice

Surface-finish quality of machined plumbing and automotive fasteners drastically improved after C&C Automatics upgraded its barstock to Carpenter Technology Corp. Project 70+ stainless steel.

Plumbing and automotive fittings machined by C&C Automatics Inc., Newark, N.Y. (ccautomatics.com), were originally made from 303 stainless-steel bar stock. But the high-speed shave tool needed a severe angle to cut the fittings. A built-up edge would develop and break down so often that C&C couldn't meet production demands.

Upgrading the barstock to Project 70+ stainless steel from Carpenter Technology Corp., (cartech.com), reduced wear problems on the shave tools. Moreover, the inherent nongalling properties of the 303 P70+ CF, ANL alloy eases cutting and helps reduce scratches and tears that ruin precision finishes.

"We were running at 15% of our quoted job rates before we swapped stainless steels," said C&C Automatics' Craig Parsons. "We were approaching a point where it wasn't profitable to keep making the fittings, but changing the steel alone moved the efficiency rate above 50%."

While machining precision parts, it is best to run machines at a consistent setting. C&C prefers to set up a machining tool and let it run as long as possible. The slightest variation in settings can cause imperfections and downtime as technicians make the necessary adjustments.

Knurl-formed fittings for the automotive industry are the majority of C&C's stainless-steel products, but profitability suffers if machines sit idle. Tool breakdowns require that machinists stop working, replace the tool, and reset the machinery. A set of knurls generally costs about $45, but time spent replacing them is worth even more.

C&C replaced knurl tools almost daily with the original 303 stainless steel machining stock. But knurls upgraded to Project 70+ stainless steel last more than three days, boosting throughput and part production. Additionally, the company was originally producing 5,000 automotive stainless steel fittings per knurl set. Switching to 303 P70+ CF, ANL barstock now lets C&C get 15,000 parts out of every knurl set.