Historical Markers
National Tube Works Historical Marker
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National Tube Works

Pittsburgh Region


Marker Location:
PA148 (Lysle Blvd.), subway entrance to plant, McKeesport

Dedication Date:
January 15, 1991

Behind the Marker

Color postcard of the National Tube Works.
Postcard of the National Tube Works, circa 1910.
Gas mains, water mains, flagpoles, steam mains, automobile tubing, refinery tubes, agitators, digestors, evaporators, dephlegmators and forty-three other types of tubes flowed from the mammoth National Tube Works in McKeesport. The McKeesport plant took in a mountain of iron ore, coal, and limestone and sent out a veritable forest of tubes. While for Braddock it was rails and for Homestead it was structural shapes, at McKeesport it was tubes in all their variety and glory that made the world go round.
This promotional image shows some of the many uses for seamless and welded pipes.
McKeesport Pipe Tree, "Steel Pipe, Welded or Seamless" circa 1935.

"National Tube" had its origins with the Flagler brothers of Boston, John and Harvey. They had operated a small plant welding iron tubing in East Boston, but decided to move their operations to the Pittsburgh district to be closer to iron makers. They purchased the Fulton, Bolman Company of McKeesport, and built there in 1872 a new mill for welding tubes. Within a year the mill was turning out tubes as large as fifteen inches in diameter and twenty feet long.

National Tube Co Inspectors examine steel beams.
Inspectors at the National Tube Company examining steel tubes, circa 1944.
All welded tubes started out as sheets cut to size known as "skelp." For smaller tubes, "butt" welding in a single step formed the tube and welded its edges together inside a cone-shaped "welding bell," while for larger tubes the sheet-like "skelp" was first rolled into a tube and then closed up by "lap" welding in separate welding rolls.

In the 1880s the company installed rolling mills to form the "skelp" for tube making, built its own blast furnaces to make raw iron, and increased its lap and butt welding furnaces to ten and seven, respectively. Tubes in great variety thus came from a highly automated factory.
Between 1891 and 1901, three waves of corporate mergers washed over McKeesport.

Seamless tube manufacture, Koppel Steel in Ambridge, PA, 2006, by Don Giles.
In 1891, the Flagler brothers consolidated their various iron and steelmaking interests together with the South Side works of Republic Iron into an $11.5 million concern. Soon after, McKeesport built a new Bessemer steel plant and literally retired its numerous skilled iron puddlers.

In 1899 a Morgan-financed merger brought sixteen of the country's largest pipe and tube manufacturers into one dominant tube concern, still known as National Tube. Among the prominent firms was the Riverside Iron Works, which sold steel tubes to John D. Rockefeller's Standard Oil, the world's largest tube consumer. In the third and final wave, the U.S. Steel Corporation in 1901 merged together the remaining tube competitors, including the independent Shelby Steel Tube.

With an active union tradition, McKeesport was a central battleground in the 1909 and 1919 steel strikes. In 1909, National Tube dismantled the town's Dewees Wood plant, because, as a corporation official declared, "McKeesport . . . has a population that is largely in sympathy with lawlessness, and has a mayor who will not use his police to protect the property of manufacturers and will not permit a nonunion man seeking work to enter town."

Group photo of workers in the general machine shop of U.S. Steel's National Tube Company in McKeesport, Allegheny County, 1907
General machine shop of U.S. Steel's National Tube Company in McKeesport, Allegheny...
During themarker1919 steel strike McKeesport's unionists defied the city's official ban and held public street meetings, although these did not prevent the strike from failing. Union activities at McKeesport, both before and after the markerSteel Workers Organizing Committee's organizing drive in the 1930s, are unusually well documented in the University of Pittsburgh's archives.

McKeesport under U.S. Steel had something of a mixed record. In the early twentieth century, the boom in the automobile and petroleum industries swelled the market for tubes. McKeesport, however, did not install its first hot mill for making markerseamless tubes, until 1930.

Also in the 1930s the works experimented with electric arc welding, creating a distinctive "under powder" or submerged process later used extensively under the trade name Unionmelt welding. In 1950 a new electric welding mill was built to manufacture large tubes up to thirty-six inches in diameter.
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