Page 31 - MetalForming November 2019

FABRICATION
Punching
Their Way to Greater Productivity
Two metal formers—one a Midwest fabricator and the other a Canadian manufacturer of fire-equipment enclosures— increase punch-press productivity with tooling solutions.
BY JOE JANCSURAK, ASSOCIATE EDITOR
Alittle innovation goes a long way in replacing repetitive manufac- turing processes and secondary operations. A Midwest-based fabrication shop found that to be true when it dis- covered an alternative to its use of nib- bling, the practice of producing large holes using a small punch that makes a series of overlapping hits. For a Canadian manufacturer of fire-hose and extinguish- er cabinets, innovation came in the form of finding a way to eliminate its need for a three-piece spot welded assembly.
No More Nibbling
While nibbling works, says Gary Troxell, sales engineer at Mate Precision Tooling, it requires many strikes to achieve the necessary holes. For the fabrication shop, this resulted in 90 sec. to nibble each part, which the company considered a problem.
The solution? A quad-radius tool and auto-index station that enables 8-, 12-, 16- and 20-in.-dia. punches in a 2-in. station, saving 30 sec. per part. With this fabricator producing 2000 parts/month, it saved 1000 min. (16.7 hr). At a labor rate of $45/hr., the cus- tomer saved $750/month or $9000/yr.
Another and perhaps more impor- tant way to look at the 16.7 hr. saved:
“The company gained 16.7 hr./month of production time, or 200 annual bill- able hours,” says Troxell. “At a billable shop time of $125/hr., there’s potential to increase annual billing by $25,000.”
No More Spot Welding
Toronto, Ontario-based Williams Brothers discovered that it could elimi- nate secondary spot-welding operations when manufacturing fire-equipment cabinets. Working with Peter Visser, sales engineer at Mate, the OEM employed a SnapLock lance-and-form tool that pro- duces self-locking, spring-loaded tabs that snap securely into prepunched holes, forming a mechanical lock and eliminat-
This radius tool, designed for punch presses with auto-index stations, pro- duces large holes using far fewer hits than a nibbling punch.
ing the need for welding. This involved learning how to set up the press brake to achieve consistent bends to ensure that the parts snap and lock together.
The benefit in making the switch: eliminating the need for a three-piece box that was produced on a slit line and required three spot welders. Williams Brothers General Manager Shaun Dooner says that the elimination of the spot welding operation allowed the company to redeploy three expe- rienced employees to other areas with- in the company, such as painting/fin- ishing and forming/bending.
“By eliminating the need to hire three new full-time employees for the other operations,” says Dooner, “we saved the company more than $93,000 in combined salaries.” MF
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This SnapLock lance-and-form tool produces self-locking, spring-loaded tabs that snap securely into pre-punched holes, eliminating the need for welding or additional assem- bly operations.