We have rehabilitated approximately 300,000 linear feet of various type and size pipe using HDPE.
Sliplining is a popular and trusted trenchless method that allows the rehabilitation of deteriorating pipe by inserting a smaller pipe into an existing pipe. As a trenchless method, sliplining can be applied to either pressure or gravity pipelines.
Water, sanitary and storm sewers can be renewed with minimum excavation. When
done properly, sliplining ensures that the rehabilitated pipe and lateral connections
are leak-tight, corrosion resistant and capable of even greater flow rates.
In the sliplining process, a winch cable is inserted through the existing line
and then attached to the front of the new liner pipe. The new pipe is then
pulled into the existing pipe and reconnected to the system.
- Sliplining can be used on most types of pipe and is suitable
for potable water.
- Installation is rapid and causes little disturbance to
- Hydraulic performance is improved due to an improved friction
- Installation can be completed in live lines without bypass
- Structural strength and life expectancy is added to existing
- Service connections are replaced with new taps to ensure
- Sliplining is a cost-effective alternative to excavation,
replacement and CIPP methods.
A typical sliplining project consists of the following steps:
- The pipe is cleaned to remove tuberculation or any debris
that may be present. It is then televised for proper measurements and to make
sure there are no obstructions or protrusions from service taps or broken or separated
- The excavation points are located at connections that would
have to be excavated anyway. The HDPE is then pulled through from the downstream manhole. The configuration of the excavation at the insertion end
is important because the trench's length-to-depth ratio must be large enough to
minimize the bending stress on the HDPE to be inserted and on the welds between sections.
The actual ratio depends on the diameter of the HDPE pipe; 10:1 ratios are not uncommon.
- Workers then butt weld sections of HDPE together if they
haven't already done so, and attach a tapered nosepiece to the front of the
HDPE. This piece is fitted with a winch hook to pull the HDPE through the
- The HDPE is inserted into the host pipe and pulled through
by the winch. Care is taken to avoid damage to the HDPE at the point of insertion.
- Service connections are then reestablished and the void
between the HDPE and existing pipe are grouted in at the man holes.
With proper planning, sliplining is a cost effective method for the rehabilitation
of aging sanitary and storm sewer collection systems, extending the service life
of these systems for many decades to come.