CIPP is usually a more cost-effective and less disruptive process than traditional ‘dig and replace’ pipe repair methods. A cured-in-place pipe (CIPP) is one of several trenchless rehabilitation methods used to repair existing pipelines. The technology is one of the most widely used rehabilitation methods for lateral sewers, storm pipelines and water mains, as curing lining within the existing pipe can eliminate infiltration, add strength to a pipeline,
prevent pipe delamination/scaling and prevent corrosion. CIPP methods offer pipeline engineers the option to significantly extend the life expectancy of an existing pipeline without the need to remove the old pipeline from its route, whether this is a buried pipe, a surface network, or a pipeline within a building.
CIPP benefits
CIPP lining systems are considered ‘trenchless technologies,’ so there are multiple benefits to using this repair and curing method to rehabilitate a pipeline that is leaking or structurally unsound, including:
• No costly excavation and replacement of the pipe required.
• The rehabilitation operation is quicker, more convenient and saves time on site.
• It is less disruptive to the locality, as the site footprint is smaller and can be done
via existing access points.
• It is environmentally friendly, as there is a minimal ecological disturbance.
• When correctly utilised, it can save money, lower costs and be safer for the
workforce.
How does CIPP lining work?
The lining process requires inverting through or pulling in a resin-saturated flexible felt or fibreglass liner into the damaged or degraded pipe. This process is usually done from an existing manhole or chamber access in the lateral system, inside a house or at an exterior point. Inflating the liner with air pressure then transports the coated liner through the damaged pipe, flexing around bends to press against the inside walls. After the liner system is in place, the system can be cured by hot water, steam, or ultra-violet (UV) light, the cured liner then creates a seamless, durable pipeline within the existing pipe.
CIPP Curing Methods
Today, there are a variety of installation and curing methods to repair a pipeline with CIPP.
Existing host pipe materials, ground conditions, the size of the pipe, and the weather will
affect which curing method is appropriate. Ambient Cure: If users are only repairing or rehabilitating a short length of pipe, they could use an ambient curing process. Ambient cure resins are used in short drag-in and inversion liners and patch repair systems. By using a simple 2 or 3-part resin system, the process of curing begins as soon as the components meet each other.
• Advantage of Ambient cure: The Ambient cure method requires minimal equipment
for the installation, therefore implying small set-up costs.
• Disadvantage of Ambient cure: Ambient cures are limited to the length of repair that
is possible due to the time constraints of the resin, and environmental factors such as
temperature that significantly impact that affect the speed of cure and curing time.
Hot Water Cure: Curing with hot water is the original method for CIPP lining techniques.
After the liner is in place and inflated with cold water, lining engineers can begin circulating
hot water into the system from the hot water boiler at the access points. The circulation
creates continuous water flow from one end of the liner to the other, and the appropriate
water temperature is held until the resin fully cures. When the pipe is fully cured, cold
water is then circulated to cool the liner.
• Advantage of Hot Water cure: Longer lengths are possible with hot water curing than
with UV methods.
• Disadvantage of Hot Water cure: Most heat-cure resins release an odour. The odour
comes from styrene, which is the liquid that reacts with heat and hardens to form the
liner. It is unsure of any health impacts from breathing in these emissions. There is a
high-cost impact of maintaining the installation equipment such as boilers and trailers.
Steam Cure: Compared to a hot water cure process, steam is typically faster because steam can transfer heat more quickly than water. Once the liner is in place, air pressure is used to inflate and expand the liner against the pipe walls. Boilers are then used to produce the steam which is introduced into the pressurised air through one end of the liner. After the curing is complete, airflow is introduced to cool the liner and prevent shrinkage.
• Advantage of Steam cure: Longer lengths are possible with steam curing than with UV
methods. Steam is typically faster than hot water curing methods because steam can
transfer heat more quickly than water therefore saving time on site.
• Disadvantage of Steam cure: There is a risk of blistering of the liner caused by a lack of
temperature control. Caused by heat, a blister can inhibit flow and cause blockages or
accelerate the degradation of the liner.
UV LED Curing
A more modern method of CIPP is UV LED curing which uses no water at all and cures with fibreglass or felt liners. A Glass Reinforced Polyester (GRP) or felt liner is impregnated with a unique resin into the sewer or drain.
Introducing air pressure to the liner, it begins to expand and press against the pipe walls. A UV light train and CCTV camera is inserted into the line to align and record the condition of the pipe. The light train is then activated and pulled back through the liner at a regulated
speed to cure the liner. The cure is controlled by the light train’s speed while this entire process is computer-monitored for temperature, pressure, and cure rate to ensure a successful installation.
• Advantage of UV LED cure: A stronger and more durable method than steam and hot curing. UV LED curing significantly is more efficient as it takes less time and has an even smaller environmental footprint. Furthermore, unlike heat curing, UV curing has no styrene emission.
• Disadvantage of UV LED cure: The process of UV curing large diameters requires a greater investment than other options. There is a limitation on installing long lengths over 100 m dependant on the UV rig set up.
UV LED Curing Options
S1E has partnered with two great brands to offer UV-cured CIPP lining systems to provides seamless results on site. The Brawo Magnavity LED light-curing system and the Starlight UV lining system offer the same benefits of using a UV method but are both unique in their field or should that be pipe, of expertise.
The Starlight UV lining system from I.S.T. Germany is supplied exclusively in the UK by S1E. The system is a versatile and mobile UV curing machine, with fast curing time for DN100 to DN400 and perfect for mainline pipe repairs and thick or Fibreglass GRP liners.
Not only does the system combine perfectly with the Starlight Plus liner, it can be used with other UV liners if preferred.
S1E has recently become the first UK reseller of the Brawo Magnavity LED lining system, from BRAWO Systems. The new innovative solution has already been making a significant impact on two water utility companies in the UK, significantly speeding up the previously
difficult process of lining both rainwater and foul stack pipes, with less disruption, using far less energy and creating less material waste, as well as successfully re-rounding and lining the common challenge of Pitch-Fibre Pipes with areas of deformation exceeding 40%, to leave it fully serviceable and flowing free.
The Brawo Magnavity system is ideal for sewer pipes, connection pipes with bends or pipes from shaft to shaft. It is perfectly matched to install the Brawoliner product range, so it has very good bend flexibility while also being smart, efficient, and strong.
Summary
There are many factors to take into consideration when deciding which CIPP lining process to use but overall CIPP installations can reduce costs by 40% to 60% and result in less disturbance to people and the environment when compared to excavation methods. More and more organisations are moving away from traditional dig-and-replace methods and are advocating for CIPP trenchless technology.
Here at S1E Ltd the company supplies certified and quality CIPP lining Equipment and Systems through an experienced sales team which is always available to help.
Article was provided by S1E Website: www.s1e.co.uk
