Page 40 - Trenchless Technology Piping Installation and Inspection

New Pipeline Installations 15

FIGURE 1.11 Inside view of a utility tunneling operations.

tunneling, the jacking frame, intermediate jacking stations, thrust
block, and lubrication and pumping equipment are not required. Since
the pipe sections are not jacked in the utility-tunneling method, the
pipes are designed and manufactured to take only permanent loads.
Figure 1.11 presents an inside view of a utility-tunneling project.
1.6.3 Horizontal Earth Boring
In the horizontal Earth-boring methods (HEBs), workers may work
in the shaft or pit, but usually do not enter the borehole or enter the
installed pipe. Therefore, these methods can be used for small-
diameter pipe installations (4 in. or more). The horizontal Earth-
boring method is further divided into a number of methods as
shown in Fig. 1.12. These methods are briefly described in the fol-
lowing sections.
Horizontal Auger-Boring Method
The horizontal auger-boring (HAB) method is a cost-effective pipe-
jacking operation for installing a steel casing pipe where the pipe is

Horizontal Earth
boring

Horizontal auger Horizontal Microtunneling Pilot-tube Pipe ramming
boring directional driling microtunneling
FIGURE 1.12 Horizontal Earth-boring methods.