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Special stainless steel proves a fitting solution

July 1, 2004
C& C Automatics Inc. in Newark, N.Y., produces over 20 million fittings annually. Out of these, there are plumbing-hose fittings that require extremely smooth finishes and mass-produced automotive fittings. For both these jobs, the grade of stainless

For fitting manufacturing at C&C Automatics, Project 70+ stainless steel not only improves part-surface finishes but also extends tool life.

C& C Automatics Inc. in Newark, N.Y., produces over 20 million fittings annually. Out of these, there are plumbing-hose fittings that require extremely smooth finishes and mass-produced automotive fittings. For both these jobs, the grade of stainless steel used was causing problems.

For the plumbing fittings, C&C produced the high-quality surface finishes with a shave tool. However, because of the type of part raw material used, the tool needed to run at such a severe angle that it developed edge build-up and broke down so often that the shop couldn't produce enough parts to meet job-cost estimates.

While machining the knurl-formed automotive fittings, tool breakdowns had machinists stopping work, replacing tools, and resetting the machinery. A set of knurls costs about $45 each, but time spent replacing them was even more costly.

By switching to Project 70+ stainless steel from Carpenter, C&C eliminated problems with both jobs. The material reduces shaving-tool wear for the plumbing fittings through its nongalling properties, which make cutting easier to prevent scratching and tearing that can ruin a precision finish.

For the automotive fittings, Project 70+ increased part production per set of knurls. With its previous material, C&C produced 5,000 fittings/tool out of 9 /32-in. 303 stainless steel machining bar. Project 70+ CF 303, ANL, 0.2812-in. barstock upped that number to 15,000 fittings/set of knurls. And instead of lasting about one day, knurls now cut for three before needing replaced.

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

Carpenter Technology Corp.
Wyomissing, Pa.
cartech.com