Page 40 - MetalForming December 2013

Tooling Technology
Tricky Bends
on
Press Brakes
...made to heavy gauge stainless steel help New York’s Freedom Tower reach inspiring height.
One World Trade Center, also known as the Freedom Tower, has risen to fill the void left in the Manhattan skyline following 9/11. It now stands at 1776 ft.—the tallest building in the Western Hemisphere.
At the top of the tower, a 400-ft. spire projects upward. It’s not only a symbol of perseverance, but also serves to support a worldclass broadcast antenna. The 18-piece steel spire, which weighs 800 tons, was manufac- tured at fabricating facilities in Canada and New Jersey, and then shipped to Ground Zero. The final subassembly, comprising the top 50 ft. of the spire, is a specialized stainless-steel beacon weighing nearly 14 tons.
Made in Brooklyn, Regardless of Hurricane Sandy
Brooklyn-based Kammetal, Inc., a full-service metal fabrication company specializing in architectural and orna- mental metals, was contracted by struc- tural-steel fabrication firm DCM Erec- tors to fabricate and install the architectural stainless-steel cladding that surrounds the beacon.
“We were real-
ly honored to be
part of this proj-
ect,” says Kam-
metal president
Sam Kusack.
“We’re all New
Yorkers, so the project had special meaning to everyone in our company. Taking part in the rebuilding of the towers has meant so much to me and everyone in our company.”
Fabrication of the cladding began in the summer of 2012, but was delayed after Hurricane Sandy hit the East Coast. Kammetal is located in the Red Hook neighborhood of Brooklyn, where water from the storm surge reached 6 ft. above street level.
According to Kusack, the compa- ny’s main shop floor sits about 4 ft. above street level, and was under 30 in. of flood surge during the storm. Every piece of equipment was submerged, garbage was everywhere and the shop was without power for five weeks.
Once power was restored, the equip- ment needed to be repaired before the shop could return to business as usual.
38 MetalForming/December 2013
www.metalformingmagazine.com
Kammetal processed 20,000 lb. of 1/4-in.-thick Type 316 stainless steel to create 7 tons of decorative cladding that now sits atop the spire of One World Trade Center.
All told, downtime after the hurricane added about six weeks to what would have been a five-month job.
Despite these overwhelming set- backs, the company processed 20,000 lb. of 1⁄4-in. Type 316 stainless steel to create 7 tons of decorative cladding that now sits atop the spire.
Tricky Press-Brake Bending
To fabricate the decorative cladding, Kammetal laser-cut panels for the spire’s glass and stainless steel struc- ture. Press-brake operators then formed the thick stainless steel, per- forming multiple acute-angle bends in each piece. Bending the 7-gauge stainless steel into acute angles proved to be a fairly complex operation. To accomplish these tricky bends, Kam- metal relied on precision-ground press-brake tooling (WT Style Precision