The Rolling of Rails and Structural Shapes
It will be readily understood after reading the above, that, instead of using plain rolls, mills for rolling steel rails, I beams, channels, angles, Z bars, rods, etc., must have grooved rolls. For these products the first pass will be through a groove slightly smaller than the bloom or billet. Successive passes will be through other grooves in the same set of rolls which will gradually make smaller and bring more nearly to the finished shape the piece being rolled.
Rail in the Finishing Rolls
Before our eyes the white-hot bloom enters the three-high mill, goes backward and forward through the rolls and very shortly assumes the general shape desired. Each pass thereafter brings it nearer to the finished shape. Rails, for instance, are rolled out from the blooms into one long rail perhaps 140 feet in length which glides along like a huge snake to the swiftly revolving “hot” saws which are so spaced that four 33–foot rails are sawed from it at the same time. As the rails pass from the saws to the cooling bed they are marked by a revolving stamp. When cool they go to the straightening yard, are straightened, drilled, inspected and later loaded into cars for shipment.
The production of all kinds of finished rolled iron and steel products in the United States during the past twenty-eight years is given in the following table which shows how extensive are our rolling mill industries and the rapidity of their development.
| Year | Iron and Steel Rails | Plates and Sheets | Nail Plate | Wire Rods | Structural Shapes | All Other Finished Rolled Prod. | Total Gross Tons |
|---|---|---|---|---|---|---|---|
| 1887 | 2,139,640 | 603,355 | 308,432 | 2,184,279 | 5,235,706 | ||
| 1890 | 1,885,307 | 809,981 | 251,828 | 457,099 | 2,618,660 | 6,022,875 | |
| 1895 | 1,306,135 | 991,459 | 95,085 | 791,130 | 517,920 | 2,487,845 | 6,189,574 |
| 1899 | 2,272,700 | 1,903,505 | 85,015 | 1,036,398 | 850,376 | 4,146,425 | 10,294,419 |
| 1901 | 2,874,639 | 2,254,425 | 68,850 | 1,365,934 | 1,013,150 | 4,772,329 | 12,349,327 |
| 1903 | 2,992,477 | 2,599,665 | 64,102 | 1,503,455 | 1,095,813 | 4,952,185 | 13,207,697 |
| 1905 | 3,375,929 | 3,532,230 | 64,542 | 1,808,688 | 1,660,519 | 6,398,107 | 16,840,015 |
| 1907 | 3,633,654 | 4,248,832 | 52,027 | 2,017,583 | 1,940,352 | 7,972,374 | 19,864,822 |
| 1909 | 3,023,845 | 4,234,346 | 63,746 | 2,335,685 | 2,275,562 | 7,711,506 | 19,644,690 |
| 1911 | 2,822,790 | 4,488,049 | 48,522 | 2,450,453 | 1,912,367 | 7,316,990 | 19,039,171 |
| 1913 | 3,502,780 | 5,751,037 | 37,503 | 2,464,807 | 3,004,972 | 10,030,144 | 24,791,243 |
| 1915 | 2,204,203 | 6,077,694 | 31,929 | 3,095,907 | 2,437,003 | 10,546,188 | 24,392,924 |