Upon completion of this chapter, you will be able to do the following:
Describe the two methods of manufacturing piping and tubing, and discuss
the different types and sizes of each.
Identify some of the fittings used for shipboard pipefitting operations, and
describe the proper removal and installation procedures to follow.
Identify the various valves used in piping systems.
Describe the type, class, pressures, and number marking system of standard
pipefittings and piping materials used on board U.S. naval ships.
Describe the design, types, and sizes of piping systems, and the characteristics
of liquids, gases, and vapors carried by shipboard piping systems.
Identify, the hazards and safety precautions involved with piping systems.
Describe the various materials used in insulation and lagging of piping
systems, and explain the hazards and safety requirements involved.
for each tubular product is established by the
manufacturer. If the manufacturer calls a product
As a Hull Maintenance Technician, you will
pipe, it is pipe. If the manufacturer calls it tubing,
repair or modify piping systems, and you may also
it is tubing.
install new systems. To do this, you will need to
know the materials you should use. These include
In the Navy, however, a distinction is made
pipes, tubes, valves, traps, drains, strainers,
between pipe and tubing. This distinction is based
connection fittings, expansion joints, packing, and
on the manner in which the sizes of the tubular
products are identified.
gaskets. The type of system you are working on will
determine whether you use iron, steel, copper,
plastic, or alloy materials.
There are three important dimensions of any
tubular product: outside diameter (OD), inside
In this chapter, we will discuss pipefitting
diameter (ID), and wall thickness. A tubular
materials and the different types of piping systems.
product is called TUBING if its size is identified by
actual measured OD and by actual measured wall
thickness. A tubular product is called PIPE if its
PIPING AND TUBING
size is identified by a nominal dimension called iron
pipe size (IPS) and by reference to a schedule
The Naval Sea Systems Command defines piping
designation for its wall thickness.
as an assembly that is composed of pipe or tubing,
valves, fittings, and related components that form
The size identification of tubing is simple
either a whole or part of a system that is to be used
because it consists of actual measured
to transfer fluids (liquids and gases).
d i m e n s i o n s . However, the terms used for
i d e n t i f y i n g pipe sizes will require some
It is a little harder to define pipe and tubing. In
explanation. A nominal dimension such as IPS is
commercial usage, there is no clear distinction
close, but not necessarily identical, to the actual
between pipe and tubing. The correct designation
measured dimension. For example, a pipe with a