Page 298 - Trenchless Technology Piping Installation and Inspection

262 Cha pte r S i x

FIGURE 6.16 Insert a tee fi ttings for sewer lateral connections. (Source:
Handbook of Polyethylene Pipe, 2008.)

Polyethylene strap-on
service saddle
Stainless steel
Elastomeric gasket
between saddle and liner band clamps
Extrusion weld
PVC 45° elbow (optional)
PVC pipe
Polyethylene branch saddle
Electrofusion saddle fused onto liner
with gasketed socket
outlet
Side-wall
New PE main fusion bead
FIGURE 6.17 Pipe fusion and strap-on saddle sewer lateral connections. (Source:
Handbook of Polyethylene Pipe, 2008.)

condition for the fusion operation. Strap-on saddles use a PE or PVC
saddle that are lined with a rubber layer; the saddle is strapped around
the main line using a stainless steel band, as shown in Fig. 6.17.
After testing and inspecting the line and the connections, the exca-
vation is backfilled and the line returned to service. Additional
details for gravity and pressure service connections are presented in
the Handbook of Polyethylene Pipe (2d ed., PPI, 2008).

6.9.12 Grooves on the Outside Surface of the Pipe
A common misconception regarding pipe bursting is that the pipe
fragments from the existing pipe can damage the HDPE pipe as it is
pulled into the cavity. British Gas conducted a detailed study on
bursting cast-iron pipes and concluded that there is no significant
damage to the HDPE replacement pipes. Related supporting research