John Brown and Co., Sheffield, roll steel plates from to 1⁄8″ to 11⁄4″ in thickness. A few selected thicknesses are given below.
| Thick- ness. | Length. | Width. | Area. | |||
|---|---|---|---|---|---|---|
| in. | ft. | in. | ft. | in. | ft. | |
| 1⁄4 | 30 | 0 | 6 | 0 | 72 | |
| 3⁄8 | 35 | 0 | 6 | 9 | 120 | |
| 1⁄2 | 40 | 0 | 8 | 0 | 130 | |
| 3⁄4 | 40 | 0 | 9 | 6 | 180 | |
| 1 | 40 | 0 | 9 | 6 | 180 | |
| 1 | 1⁄4 | 40 | 0 | 9 | 6 | 180 |
Circular and square plates of the same thicknesses can be rolled as follows:—
| Thick- ness. | Diameter. | Square. | |||
|---|---|---|---|---|---|
| in. | ft. | in. | ft. | in. | |
| 1⁄4 | 6 | 6 | 6 | 6 | |
| 3⁄8 | 7 | 0 | 7 | 0 | |
| 1⁄2 | 8 | 3 | 8 | 3 | |
| 3⁄4 | 10 | 6 | 9 | 9 | |
| 1 | 10 | 6 | 9 | 9 | |
| 1 | 1⁄4 | 10 | 6 | 9 | 9 |
The Dalzell Steel Works of David Colville and Sons, make a difference in the extras in the case of steel boiler and of ship plates. Ordinary prices are charged to 84″ wide in boiler plates, but to 72″ only in ship plates. Above that they charge 5s. per ton for every 3″, or part of 3″. So in weight, 40 cwt. is the limit for boiler plates, and 30 cwt. for ship plates; over those 5s. per ton is charged for every 5 cwt., or part of 5 cwt. Circular plates for boiler ends and crowns are rolled by David Colville and Sons, who supply at ordinary prices the following: 3⁄4″ thick, 9′ 10″ diameter; 11⁄16″, 9′ 6″; 5⁄8″, 9′, and 9⁄16″, 8′ 6″.
As a sample of the usual limiting sizes of iron plates, I give the following:—It consists of a few selected Snedshill plates rolled by the Lilleshall Company, one of the most favourably known Shropshire houses. They roll iron sheets and boiler plates from 1⁄16″ to 1″ in thickness, advancing by thirty-seconds to 3⁄16″, and by sixteenths to 1″.
| Thick- ness. | Length. | Width. | Area. | |||
|---|---|---|---|---|---|---|
| in. | ft. | in. | ft. | in. | ft. | |
| 1⁄4 | 30 | 0 | 5 | 0 | 5 | |
| 3⁄8 | 30 | 0 | 5 | 6 | 7 | |
| 1⁄2 | 30 | 0 | 6 | 0 | 8 | |
| 5⁄8 | 30 | 0 | 6 | 0 | 80 | |
| 3⁄4 | 30 | 0 | 6 | 0 | 80 | |
| 1 | 30 | 0 | 6 | 0 | 80 | |
It will be observed that the limiting sizes of iron are much less than those of steel.
The Butterly Company roll both iron and steel plates. The limiting weights and dimensions are as follows:—For iron boiler quality, 8 cwt., above that the extra prices are, 20s., 40s., 60s., 80s. respectively, from 8 cwt. to 10 cwt., 10 cwt. to 12 cwt., 12 cwt. to 14 cwt., and 14 cwt. to 16 cwt. respectively. For bridge quality, 10 cwt. is the limit, and extras are 20s. and 40s., from 10 cwt. to 12 cwt., and from 12 cwt. to 16 cwt. respectively. Area 60′, and for every 10′ or part above that, 20s.; length 25′; width 4′6″; over those various extras, ranging from 20s. to 80s.