Installing Cured-In-Place-Pipe (CIPP) Lateral Lining
Inversion Method For Rehabilitation Of Existing Pipelines
The intent of this cured-in-place lateral lining specification is to provide reconstruction of sewer collection laterals without excavating the entire existing pipeline.
The existing pipe reconstruction will be accomplished using a scrim reinforced liner tube measured to exact length and inside diameter utilizing a thermosetting resin that meets required physical and chemical resistance properties. The scrim reinforced liner will be impregnated with resin then loaded into an approved air pressured launching system. The liner will be aligned to the open end of the existing lateral pipe. Once the liner is aligned, the launching system will invert the resin-impregnated liner with air pressure. The inversion process is completed once the liner has fully inverted to the sewer main collection pipe, stopping at the connection. The liner will be open to allow the calibration tube to invert beyond the liner end at the sewer main connection. A calibration tube is then inverted into the liner holding the liner in place during the curing process. At no time will the calibration tube lose air pressure and be re-pressurized during the inversion process. The calibration tube will be sealed at the sewer main, holding air pressure to secure the liner against the existing host pipe until the liner is fully cured. After the resin-impregnated liner is fully cured, the calibration tube is removed. The sewer lateral collection pipe will be immediately televised for the inspector’s approval. A copy of the televised inspection must be recorded on VHS format for future reference.
The liner tube will consist of scrim reinforcement and needled felt. The liner tube will be fabricated together using a butt stitched seam sealing process with a heat welded sealing tape to ensure airtight seal. The liner tube is to be manufactured in the United States. The liner tube will be capable of carrying resin and withstanding installation pressures and curing temperatures. The liner tube Will be lined on one side with a translucent impermeable chemically resistant polyvinylchloride (PVC) waterproof coating. This coating will be on the inner lateral collection lined pipe after curing is completed. The coating will provide a smooth and seamless inner wall. The resin will be a two-part, 100% solids epoxy containing no styrene. The epoxy resin shall be formulated to have a gel (pot) life of approximately 30 minutes with a set cure time of three (3) hours. The epoxy shall ambient cure by internal exothermic chemical reaction. The scrim reinforced / seam stitched / heat welded seam tape / felt liner tube and resin will upon installation meet and/or exceed minimum testing standards as required by ICC, ASTM, IAPMO and ANSI/NSF International. All materials must have 3rd party testing provided by independent laboratory. The materials must be ANSI/NSF Standard-14 approved, IAPMO Certified for small diameter pipe lining in Sewer Pipes and Vents, and must be certified by the International Code Council for the International Plumbing Code and the International Residential Code. The scrim reinforced / seam stitched / heat welded seam tape / felt liner tube and resin must have NSF Standard 14, and ICC-ES denoted on the tube.
- 3.01 – Required Cured-In-Place Lateral Lining Standards Minimum Flexural Strength (ASTM D-790) 4,500 PSI Flexural Modulus (ASTM D-790) 250,000 PSI Tensile Strength (ASTM D-638) 3,000 PSI Compressive Strength (ASTM D-695) 4,000 PSI Tensile Elongation (ASTM D-638) 5 PSI Chemical Resistance (ASTM D-543) < 20% loss Leakage Test* (NSF Standard 14) 0/gal/in/day
* Leakage test performed by ANSI/NSF International Flexural Strength (ASTM D-790) 10,000 PSI Flexural Modulus (ASTM D-790) 350,000 PSI Tensile Strength (ASTM D-638) 5,500 PSI Compressive Strength (ASTM D-695) 4,500 PSI Tensile Elongation (ASTM D-638) 5 PSI Chemical Resistance (ASTM D-543) < 20% loss Leakage Test* (NSF Standard 14) 0/gal/in/day * Leakage test performed by ANSI/NSF International
Manufacturer must have United States based manufacturing head quarters. The manufacturer must have at least 5 years of manufacturing / supplying C.I.P.P. Air Inversion Liner Tube and Materials. The manufacturing plant has a Quality Assurance / Quality Control program in place and overseen by NSF International and IAPMO R&T Laboratories.
4.00 Inversion Process (ASTM F1216)
Blueworks follows the Standard Practice for Rehabilitation of Existing Pipelines and Conduits by the Inversion And Curing of a Resin-Impregnated Tube set by ASTM International. This process is used for projects that require the rehabilitation of conduits through the use of a resin-impregnated tube inverted through the existing conduit.
- 4.01 – The owner shall be notified 24 hours in advance of project start time. No building utilities, such as toilets, sinks, dishwasher, laundry washer, bath tubs or sump pumps will be used during the installation and curing process. Generally no by-pass pumping is needed.
- 4.02 – Lateral Sewer Collection Pipe must be cleaned thoroughly prior to installation of liner. All sand, rocks, gravel, grease, mud, sludge, and other debris must be removed from the invert to permit proper installation. Roots will need to be removed to the extent necessary to effectively line the entire pipe.
- 4.03 – The existing Lateral Sewer Collection Pipe will be inspected using a mini-televising color camera system capable of viewing the interior condition of the host pipe. The TV inspection must be performed within 5 hours prior to installation of liner tube.
- 4.04 – The resin-impregnated liner tube will be kept clean and loaded directly into the air pressured launching system. The launching system will be aligned to the existing host pipe for proper installation.
- 4.05 – The resin will not be contaminated and/or diluted prior to installation.
- 4.06 – The liner tube will be inverted using air pressure, inverting the liner inside-out until the liner tube reaches the sewer main collection pipeline. The liner tube will be open and not sealed off. The liner tube will be designed to fit tightly against the host pipe annular space and gaps. A calibration tube will be inverted inside the liner tube to ensure the liner is tight against the host pipe until fully cured. The resin-impregnated liner tube will cure within 4 hours without external heat sources.
- 4.07 – Once the curing process is finished, the calibration tube is removed and the lateral sewer collection pipe is immediately inspected for final acceptance. The new lined pipe will be free of any foreign objects providing a smooth, seamless and continuous lined pipe from entry point to main sewer connection pipe.
- 4.08 – Any liner tube protruding from the lateral sewer collection pipe into the main sewer pipeline will be removed by remote robotic cutting equipment.
- 4.09 – A final TV Inspection of the lined lateral collection sewer pipe will be recorded and provided to the owner for final approval.
5.00 Final Acceptance
In addition to any specific acceptance criteria specified in the contract, the following standards shall be satisfied before final acceptance of the liner installation:
- 5.01 Finish – The finished pipe shall be continuous over the length of a run and be free from defects.
- 5.02 Defects – Any defects, which will affect the integrity of the installed pipe, will be repaired as directed by the owner.
- 5.03 Leakage – No visible leakage through the liner will be allowed.
Payment for the work included in this section will be in accordance with the prices set forth in the contract for the quantity of work performed. Progress payments will be made monthly based on the work performed during that month.