transverse and longitudinal frames in ships' hulls and
superstructures.
OTHER STEEL SHAPES
Steel and aluminum come in numerous other shapes
that are used for general structural and nonstructural usage.
Figure 13-15.--Angles.
These shapes include angle, plates, sheets, and bars.
or sheet depending on its thickness. Generally metal
The designations generally used for flat steel have
l/8 inch and thicker is classified as plate. Metal less
been established by the American Iron and Steel
than l/8 inch thick is classified as sheet metal. Since
Institute. Flat steel is designated as bar, strip, sheet, or
plate, according to the thickness, the width, and, to some
plate and sheet are used extensively by HTs, both will
extent, the rolling process by which the material was
be discussed in the following sections.
manufactured. Table 13-1 shows the designations
PLATE. --Plate is a structural shape whose cross
normally used for hot rolled carbon steels. These terms
section is in the form of a flat rectangle. Plates are
are somewhat flexible, and sometimes may overlap.
generally used as connections between other structural
The terms used to designate cold rolled, flat carbon steel
members, or as component parts of built-up structural
are very similar to those used for hot rolled, flat carbon
members. Plates are used extensively in the
steel, but differ in some details.
manufacture of ships' hulls, bulkheads, tanks,
superstructures, and other similar applications. You
Angle
will also form plate into numerous structural and
An ANGLE is a structural shape whose cross
nonstructural uses.
section resembles the letter L. It is also known as angle
Plates cut to specific sizes may be obtained in widths
iron. Two types of angles (fig. 13-15) are in common
ranging from a minimum of 6 inches to 120 inches or
use. The legs of these angles will be either equal or
unequal. The angle is identified by the dimension and
more. The thickness of plate will be l/8 inch or larger.
thickness of the legs, such as 6" 4" ". The
The edges of these plates may be either cut by shears
dimensions of the legs are found by measuring along
(sheared plates) or rolled square (universal mill plates).
the outside or backs of the legs. When an angle has
Plates are frequently referred to by their width and
unequal legs, the dimension of the wider leg is given
thickness in inches, such as plate 24" 1/2". In all cases,
first, as in the above example. The third dimension
the length is given in feet and inches, such as 7'3".
applies to the thickness of the legs, which always have
Thickness for ferrous and nonferrous plate are
equal thickness. Angles are used in general fabrication
determined by different methods.
and have limited structural applications.
Steel Plate Sizes.--You will hear steel plate
Plate and Sheet Metals
referred to by its nominal thickness or approximate
weight per square foot for a specified thickness. Steel
Metal that comes in flat rectangular pieces are
plate weighs about 2 l/2 pounds per square foot for each
known as plates and sheets. Metal is classified as a plate
Table 13-1.--Designations of Hot Rolled Carbon Steel According to Thickness and Weight
Width, inches
0.2500
0.2499
0.2030
0.1874
0.0567
0.0343
0.0254
to
to
to
to
to
to
and
thicker
0.2031
0.1875
0.0568
0.0344
0.0255
0.0142
strip
sheet
strip
strip
strip
bar
To 3 l/2 inclusive
bar
strip
strip
strip
sheet
sheet
bar
Over 3 l/2 to 6 incl.
bar
sheet
sheet
sheet
strip
strip
strip
Over 6 to 12 incl.
plate
sheet
sheet
sheet
sheet
sheet
sheet
plate
Over 12 to 32 incl.
sheet
sheet
sheet
sheet
sheet
sheet
plate
Over 32 to 48 incl.
sheet
sheet
plate
plate
sheet
plate
sheet
Over 48
13-12
