Masters of Metal: 551st mechanics mold sheets of steel

  • Published
  • By Mike W. Ray
  • Tinker Public Affairs
The 551st Commodities Maintenance Squadron sheet metal manufacturing shop makes myriad parts for aircraft undergoing maintenance at Tinker Air Force Base.
The B-52 "is our biggest customer, from cowlings to doors and other fuselage parts," said David Mason, Production Chief, Sheet Metal Manufacturing. "Our workload is diverse," he said.

The shop previously was housed in Bldg. 3001, but most of its processes relocated to Bldg. 9001 a little over a year ago, said Joe Goodwin, Production Supervisor, Sheet Metal Manufacturing. A foundry and a non-destructive inspection unit are still located in Bldg. 3001, but eventually the entire operation will be consolidated in Bldg. 9001, he indicated.
Mr. Mason and Mr. Goodwin are co-supervisors of the shop.

There's plenty of work to go around. The shop has approximately 45 employees on three shifts, Mr. Mason said. The shop sold 47,000 hours of work in calendar year 2011, a computerized database shows.

On the morning of March 12 the shop had 650 open jobs requiring an estimated 16,000 man-hours of work to complete. Those jobs were in various stages of completion, Mr. Mason said, ranging from just-logged-in to nearly finished.
The primary parts manufactured in the shop are B-52 engine cowlings: nose, side and wrap cowlings.

Workers in the shop employ a variety of presses to perform their jobs.

· A computer numeric controlled turret punch can cut out precise copies of a single part over and over again from a sheet of steel, aluminum or titanium. In "the old days," a worker had to drill holes in a metal sheet by hand and then use a band saw to cut the metal from hole to hole; consequently, parts would be approximately, but not exactly, the same size, Mr. Mason noted.

· A water jet is used to cut out parts from sheet metal with a stream of water and grit propelled at 50,000 pounds per square inch. "It can cut through 7-inch thick steel," Mr. Mason said.

· A 300-ton stretch draw press applies 600,000 pounds of pressure to shape metal parts.

· A stretch wrap press that forms extrusion and other bent angles, stretching and holding the metal while shaping it around a stationary die, to keep the metal from wrinkling while being distended.

Some of the sheet metal used in the shop must be heat treated and then frozen. When making aircraft skins, this process keeps the metal in a workable state before forming, Mr. Mason related.

As a result, sheet metal shop workers in Bldg. 9001 have to travel back and forth between Bldg. 3001 to deliver or pick up metal that must be heat-treated in an oven operated by the Propulsion Maintenance Group. Eventually an oven will be installed in the 9001 shop, Mr. Mason said.

"We have only one machine waiting to be installed," Mr. Goodwin said recently. It remains disassembled until some foundation work in Bldg. 9001 is completed, he said.
The sheet metal manufacturing shop has several thousand templates and form blocks the employees utilize to make the many different parts required to maintain airplanes at Tinker AFB. "Our job orders typically require us to make a few copies of several different parts, rather than a whole lot of the same part," Mr. Mason said.

The shop's database tracks a lot of information, including the unique ID number of every part that's ordered, the number of hours the shop was given to make a particular part and the hours actually spent manufacturing that part, the person who makes each particular part, plus the template and/or form block used to make that part and where that template or form block is stored in the shop.

The jobs performed in the sheet metal manufacturing shop "can be technical, but it's more of an art," Mr. Mason concluded.