The main purpose of insulating pipelines is to
prevent heat passage from steam or hot-water
pipes to the surrounding air or from the
surrounding air to cold-water lines. In some cold
regions, insulation also prevents water from
freezing in a pipe, especially when the pipe runs
outside a building. Thus, hot-water lines are
insulated to prevent loss of heat from the hot
water, while potable waterlines are insulated to
prevent absorption of heat in drinking water.
Insulation also subdues noise made by the flow
of water inside pipes, such as water closet
discharges. Common types of pipe insulating
materials are shown in figure 8-12.
SANITARY DRAINAGE SYSTEM
The purpose of a drainage system is to carry
sewage, rainwater, or other liquid wastes to a
point of disposal. Although there are three types
of drainage systems storm, industrial, and
sanitaryonly the latter, which is the most
common drainage system installed by the
SEABEEs, will be discussed.
The SANITARY DRAINAGE SYSTEM car-
ries sanitary and domestic wastes from a source
(or collection system) to a sewage treatment plant
or facility. Surface waters and groundwaters must
be excluded from this system to prevent overload
of the sewage treatment facilities.
The types of materials actually used will
depend upon whether the installation is
underground, outside buildings, underground
or aboveground within
buildings. The availability of certain types of
desired piping materials and fittings may also
govern the type of pipe actually used.
Figure 8-12.-Types of pipe insulation.