Full CIPP Rehabilitation with Reinstatements
For many years, small diameter CIPP contractors were struggling to find ways to reinstate connections in lined pipes. In fact, many would resort to the “MacGyver approach” of making their own cutters out of whatever they had laying around. These contraptions would then be attached to an old-fashioned sewer cable machine.
To this day, Picote Solutions sees many of the homemade solutions and listens to the stories of epic failures when trying to undertake this type of work.
As a CIPP contractor itself, Picote recognized early on that there was a need for this type of technology to be developed. Out of sheer need for a better solution for their own crews, Picote’s owner began refining the once crude way of cutting open liners and continually developed better and better ideas for this seemingly unsolvable problem. Sometime later, the Smart Cutter was born and the concept was a proven means to an end.
Using highly specialized and patented tools, the ability to cut open CIPP liners in a fast and efficient way was coupled with high-speed cable machines, which were also developed by Picote. The introduction of these machines gave Picote more ability to create tools for every situation faced inside of an aging or damaged pipe. Suddenly, high speed cleaning tools were the go-to choice for all aspects of the rehabilitation process, from start to finish.
In order to ensure the best finished product possible, Picote uses custom-designed cleaning chains and other tools, such as the Smart Spider, to clean and prepare the pipes before lining. Once the liner is installed the same high-speed cable machine is used to drive the patented cutting tools for reinstatements. In a case where the CIPP lining process does not go as planned, the high-speed machines can be used with special grinding tools to remove failures and imperfections. If that isn’t enough, the same equipment can also be used to apply a specialized epoxy coating with the addition of a Picote Coating Pump and brush casting system. The possibilities continue to grow with Picote’s line of unique cutting, cleaning and coating equipment.
As seen in the following case study, Picote’s tools have been used to rehabilitate thousands of properties just like this one.
Customer: Condo Association Tiiris Towers in Helsinki, Finland
Contractor: Picote Oy Ltd, Finland based trenchless contractor and manufacturer of small diameter tools
Original pipe: PVC
Built: 1971
Crew: Project manager and a six-member crew
Duration: 6 months
Price: +$500,000
A challenging CIPP lining project was commissioned in three buildings with fragile, brittle PVC pipe systems. These buildings had experienced leaks that had been patched for several years. A full rehabilitation with a CIPP liner from the roof top to city sewer was required (with pipes ranging from 2 to 9 in.). The project included the rehabilitation of three apartment buildings with a total of 126 apartments and businesses. Each building included six vertical stack lines (4 in.). All horizontal branch lines (from 2 to 4 in.) to kitchens and bathrooms were renovated, as well as floor drains in bathrooms and the mains (6 to 9 in.).
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Most of the renovation work was done one vertical stack line at a time; however, some lines were worked on simultaneously. All drains were cleaned with original chains powered by high-speed Millers and lined with Brawoliner (a polyester liner). Liners were allowed to ambient cure overnight. The following day, the connections were reinstated through the laterals, coming from the bathroom and kitchen, with the use of small diameter lateral cutters.
Using highly specialized and patented tools, the ability to cut open CIPP liners in a fast and efficient way was coupled with high-speed cable machines.
Two different types of lateral cutters were used: a Twister with a metal drill head surrounded by brushes that allow the cutters to stay centralized during the cutting process and a specialty PVC drill head with a safety ring. Reinstatements were finalized with a Smart Cutter, which is a cutter with a stainless steel hub with four side grinding panels.
The Smart Cutter is a practical solution, where panels can easily be changed on the spot by the technician when needed. The lateral cutters are designed so that they can be used in small pipes with multiple 90-degree bends. They stay centralized allowing efficient, yet gentle reinstatements in the brittle pipes. One technician can reinstate several connections in one hour, depending on the complexity of the drainage system (number of bends and diameter changes). It was common to reinstate more than 14 connections in an hour.
The appropriate tools allowed an efficient progression of the work flow. The Millers made the work processes safer and quicker. As Brawoliner inverts easily even in 2-in. drains with numerous bends, lining the small drains was not a problem. The cutters allowed for quick and safe reinstatements.
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After the reinstatement of the connections leading to the vertical line, horizontal branch lines were then lined from the biggest drains to the smallest (toilet, floor drain and kitchen). At Picote jobsites, a patented lining method called Branch Lining was used where the short DN50-70 liners are installed open ended with no calibration hose. In Branch Lining, two liners overlap forming a double layer on the connection. Often vertical drains are lined first, followed by the lining of a connecting branch line. The branch line is lined open-ended. The top of the cured liner in the vertical pipe is then cut open with a Twister (designed for PVC pipes) lateral cutter, which securely positions the cutter without damaging the liner or the original pipe. During the three-week rehabilitation of the mains, a bypass system allowed the residents to use the building drains normally.
Without the revolutionary development of small diameter lateral cutters, the rehabilitation of apartment buildings with CIPP liners would not be possible. However, with today’s simple mechanical cutters, reinstatements can be achieved quickly, safely, efficiently and accurately in sizes as small as 2 in.
Katja Lindy-Wilkinson is CEO and Jake Saltzman is worldwide technical director at Picote Solutions Inc.