Page 481 - Trenchless Technology Piping Installation and Inspection

Glossary of Terms 431

Repair: Reconstruction of short pipe lengths, but not the reconstruction
of a whole pipeline. Therefore, a new design life is not provided. In contrast,
in pipeline renewal, a new design life is provided to existing pipeline
system.
Replacement: Replacing an old, existing, or deteriorated pipe with a
new pipe by use of open-cut, inline replacement (pipe bursting), and/or
other new installation methods (HDD, microtunneling, etc.). The new
pipe may have a larger diameter and different pipe material from the
existing or old pipe.
Resin impregnation (wet-out): A process used in cured-in-place pipe
installation where a plastic coated fabric tube is uniformly saturated
with a liquid thermosetting resin, while air is removed from the coated
tube by means of vacuum suction.

Resins: An organic polymer, solid or liquid; usually thermoplastic or
thermosetting.
Reverse: In horizontal auger boring, the counterclockwise rotation of
the auger as viewed from the machine end.
Ring compression: The principal stress in a confined thin circular ring
subjected to external pressure.
Robot: Remote-control device with closed-circuit television (CCTV)
monitoring, used mainly in localized repair work, such as cutting away
obstructions, reopening lateral connections, grinding and refilling
defective areas, and injecting resin into cracks and cavities.

Robotic cutter: A device used to re-open house connections after the
installation of a liner without excavation.
Rod pushing: Method of forming a pilot bore by driving a closed pipe
head with rigid attachment from a launch pit into the soil, which is
displaced. See thrust boring.
Roller cone bit or reamer: A bit or reamer in which the teeth rotate on
separate, internal shafts that are usually aligned perpendicular to line.
Used for boring rock.
Rollers: The rollers that control the exact amount of resin material that is
required to properly saturate a felt tube.
Rotary rod machine: A machine used to drill earth horizontally by means
of a cutting head attached to a rotating rod (not an auger). Such drilling
may include fluid injected to the cutting head through a hollow rod.
Saddle: In horizontal auger boring, a vertical support mechanism to
hold the casing in position while starting (collaring) the bore.

Saturated tube: See impregnated tube.
SBR (styrene butadiene): Type of rubber that has good abrasion resistance
and excellent impact and cut-and-gouge resistance. Used as gasket material.