Yankee Dryer and method of fabrication
AssigneeUnited States Steel Corporation
InventorsKarl H. Klippstein, Joseph Sawdai, Charles A. Schacht, Charles G. Schilling
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Abstract
A Yankee Dryer used in drying a web of paper or like materials in which all structural components are fabricated of weldments of steel plate and forgings and in which the outer shell is formed of a weldment of steel plates expanded to roundness and machined to final dimensions. All primary welds are subject to X-ray inspection. The dryer is of lighter weight than the usual cast iron Yankee Dryers, yet designed to withstand substantially higher steam pressure within the shell.
Claims4
A method of fabricating a Yankee Dryer which has a pair of trunnions, an outer shell, heads attached to said shell and trunnions and connecting means for tying said heads together, said method comprising:
- forming a roughly cylindrical weldment of steel plates butt-welded together and being of slightly smaller diameter than the desired final diameter of said outer shell;
- expanding said weldment by about 0.5 to 1.0 percent of its diameter to provide roundness;
- welding rings to the ends of said weldment;
- stress-relieving said weldment;
- re-expanding said weldment to provide a total expansion of 1.0 to 1.5 percent of its diameter and bring the weldment close to the final dimensions of said outer shell;
- machining said weldment to the final dimensions of said outer shell;
- and
- assembling said outer shell heads and connecting means.
Dependencies are inferred from the claim text.