Chapter 3 Ships' Drawings and Diagrams

CHAPTER 3

SHIPS' DRAWINGS AND DIAGRAMS

LEARNING OBJECTIVES

Upon completion of this chapter, you should be able to do the following:

2. Describe the procedures in verifying the accuracy

1. Describe the different types of ships' drawings.

of ships' drawings and systems diagrams.

BLUEPRINTS

INTRODUCTION

Drawing or sketching is the universal language used

Blueprints are reproduced copies of mechanical or

by engineers, technicians, and skilled craftsmen.

other types of technical drawings. The term blueprint

reading means interpreting the ideas expressed by

Whether this drawing is made freehand or with drawing

others on drawings, whether the drawings are actually

instruments, it is needed to convey all the necessary

blueprints or not.

information to the individual who will fabricate and

assemble the object whether it be a building, a ship, an

aircraft, or a mechanical device. If many people are

HOW PRINTS ARE MADE

involved in the fabrication of the object, copies (prints)

are made of the original drawing or tracing so all persons

A mechanical drawing is drawn with instruments

involved will have the same information. Not only are

such as compasses, ruling pens, T-squares, triangles, and

drawings used as plans to fabricate and assemble

french curves. Prints (copies) are reproduced from

objects, they are also used to illustrate how machines,

original drawings in much the same manner as

ships, aircraft, and so on are operated, repaired, and

photographic prints are reproduced from negatives.

maintained.

The original drawings for prints are made by

The chapter contains general information about the

drawing directly on, or tracing, a drawing on a

various types of ships' drawing and system diagrams

translucent tracing paper or cloth, using black

that you should be familiar with as an IC1 or ICC. They

waterproof (india) ink or a drawing pencil. This original

include the following:

drawing is normally called a tracing "master copy."

These copies of the tracings are rarely, if ever, sent to a

Blueprints

shop or job site. Instead, reproductions of these tracings

Electrical prints

are made and distributed to persons or offices where

needed. These tracings can be used over and over

Electronic prints

indefinitely if properly handled and stored.

Electromechanical drawings

Blueprints are made from these tracings. The term

blueprints is a rather loosely used term in dealing with

Logic diagrams

reproductions of original drawings. One of the first

As an IC1 or ICC, you should have an indepth

processes devised to reproduce prints or duplicate

knowledge of how to use, care for, update, and verify

tracings produced white lines on a blue background,

the accuracy of these drawings. Drawings have a variety

hence the term blueprints. Today, however, other

of uses, and you, as a supervisor, will come to realize

methods of reproduction have been developed, and they

the importance of drawings.

produce prints of different colors. The colors may be

3-1