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Rotary table slashes part-production time

Dec. 1, 2002
An increased production of combustion turbines for power generation has spurred a corresponding increase in demand for fuel nozzles, which control the flow of fuel into the combustion chamber. Each nozzle consists of a fuel cap and several — 8 or 12

Haas vertical machining centers let DuHadaway Tool and Die Shop meet the increasing demand for combustion turbine fuel nozzles.

The fourth and fifth-axis rotary tables on its Haas vertical machining centers reduce setup times for DuHadaway's gas-tip and fuel-cap machining.

An increased production of combustion turbines for power generation has spurred a corresponding increase in demand for fuel nozzles, which control the flow of fuel into the combustion chamber. Each nozzle consists of a fuel cap and several — 8 or 12 — gas tips. To keep up with this demand, DuHadaway Tool and Die Shop Inc., a company that produces parts for power-generation units, had to also up its production of gas tips and fuel nozzles.

DuHadaway machines the gas tips out of 310 stainless steel using a Haas VF-2 vertical machining center with an HRT 210 rotary table. After eight slots are milled, the shop mills the inside of the gas tip in the same type of setup. With the internal part at a 30° angle, operators counterbore to depth, drill and ream the gas ports — holding a 0.0005-in. tolerance — and form a small radius for flow. "These operations are done in one setup," says John O'Donnell, company vice president and general manager. "The part took us about an hour to make before, but with the Haas rotary table, it takes 15 min."

"The way it was set up before, we had to manually index the gas tip for machining," explains O'Donnell. "We milled it across the top four times, used a separate fixture to set it at 30°, and then milled it one slot at a time. We now turn the gas tip around with the rotary table to position, index, and mill the eight slots."

The Haas 4th and 5th-axis rotary table also streamlines manufacturing fuel caps at DuHadaway. According to O'Donnell, the shop rotated many of the parts manually. It now writes a program to do the 8 or 12 holes in one setup.

Haas Automation Inc.
Oxnard, Calif.
www.haasCNC.com