Understanding the purpose and information in each
Correctly interpreting blueprints will reduce mistakes
block of a blueprint will greatly increase your ability to
and rework of jobs due to the wrong dimensions or
use, understand, and interpret blueprints. Depending
improperly placed components.
on their purpose, blueprints vary in size, format, and
This section will discuss the organization, lines and
content. Only the title block, revision block,
symbols, dimensions, and scales found on a blueprint.
application block, zone numbers, and the bill of
Views, detail drawings, and assembly prints will aid you
materials will be discussed in this section.
in your job and will also be discussed in this chapter.
Welding and NDT symbols, though a part of blueprints,
have already been discussed in previous chapters. It
The title block is usually located in the lower
isn't the intent of this section on blueprint reading to
right-hand corner of all blueprints. This block contains
make you an expert on blueprints. But you should have
the drawing number, the name of the part or assembly
the basic knowledge of blueprints to enable you to
that the blueprint represents, and all information
function in a shop environment until you gain further
required to identify the part or assembly. The title block
skill in reading blueprints. To gain further knowledge
also includes the name and address of the government
in blueprint reading, you should refer to Blueprint
agency or organization preparing the drawing, scale,
Reading and Sketching, NAVEDTRA 10077.
drafting record, authentication, and date the blueprint
NOTE: Only standard blueprints will be discussed
was approved (fig. 13-1).
in this section.
PARTS OF A BLUEPRINT
The revision block, shown in figure 13-2, is in the
upper right-hand corner of the print and is used for the
Blueprints are broken down into numerous
recording of all changes (revisions) to a print. It could
sections. Each section serves a different purpose.
be quite detailed depending on the frequency of changes
Figure 13-1.--Blueprint title block.
Figure 13-2.--Revision block.