The rehabilitation process begins with the careful selection of pipe segments for rehabilitation. Pipe type, age, along with the number breaks can be used as a proxy for the pipe condition and to build a SIPP lining program.
Planning begins with a full site evaluation and condition assessment. Specific details addressed during this project planning phase include environmental and regulatory compliance, traffic controls and the strategic location of the access pits. A detailed work schedule is then created to minimize impact on traffic, businesses and homeowners.
It is recommended that a contractor or installer should physically check all the dimensions supplied by the project owner to ensure accuracy.
All underground utilities must be marked at access pit locations. Traffic, pedestrian, and worker safety equipment must be installed prior to the commencement of the access pit excavation. Access pit dewatering equipment should also be installed, if required, and a Hazard Risk Analysis performed.
To minimize the impact to businesses and homeowners, access pits, measuring 6’ x 10’, can be excavated one day prior to lining. The work area must be in compliance with all federal, state, and local regulations. Subject to local health authorities, pits may need to remain until microbiological tests allow final connections to be completed.
The host pipe must be cleaned and prepared for the lining. This includes removal of encrustation, tuberculation and accumulated loose or adhered materials. This removal of interior deposits and sediment will result in improved water flow and efficiency.
In general, approved pipe cleaning technologies and surface preparation methods, before the application of the Resiline 320 liner, are:
If required by local regulation, capture all debris for proper disposal. In the case of asbestos pipes verify compliance with local, state, and federal regulations.
To verify the pipe condition and to confirm that the pipe is acceptable for lining, a closed-circuit television (CCTV) camera should be placed inside the pipe (CCTV V1). A pan and tilt camera is the preferred method of inspection of the interior of water pipes. All CCTV surveys must be recorded and provided to the project engineer. This CCTV must show and record all services, bends, sags, water infiltration locations, and leaking services.
The use of a plunger, squeegee or foam swab may be required to remove the last of the sediment, dust and/or standing water.
Repeat the cleaning process until the pipe is prepared to an approved condition to receive the Resiline 320 lining.
For 4 to 12in diameter metallic (Iron and Steel) pipes SIPP AMERICAS requires the pipe to be prepared before applying the Resiline 320, using the air borne abrasive Tomahawk pipe cleaning method or equivalent. Details on the Tomahawk pipe cleaning method can be found at https://www.envirologics.ca/technologies/cleaning-tomahawk.
For Asbestos and PVC pipe abrasive foam pigs and provide adequate pipe preparation of the Resiline 320 lining. Please contact SIPP AMERICAS for cleaning needs for a specific project.
For metallic pipe diameters 12 to 42 inches Schur-BPH drag scrappers or equivalent are recommended to prepare the pipe for Resiline 320. Information on Schur-BPH Scrappers is available at https://schurltd.co.uk/pipe-cleaning/.
SIPP Americas is confident that preparing the pipe using the Tomahawk using trained and certified personnel will produce best-in-class SIPP liners.
To ensure a quality liner is constructed SIPP Americas requires that an approved Schur BKH rig or equivalent be used. Over the past 30 years Schur-BPH has been a leader and innovator in the design spray rigs. Schur has developed a line of spray rigs for small and large projects. We are confident that SIPP lining, with a Schur rig, with trained and certified personnel, will produce best-in-class Resiline 320 liners.
The mix ratio is calculated as follows: [Weight of Activator]/[Weight of Base] x 100. The results must all be within +/-5% of the Resiline published mix ratio by weight (100:72.5). If any of the weight checks do not comply with this quality check, weight checking should be repeated until three consecutive results meet this requirement.
The lining rig needs to be located to pull the lining rig umbilical straight and in line with the pipe to be lined. Rollers should be installed, to ensure the smooth pulling of the lining umbilical. A supporting structure may need to be installed, so that pulleys supporting the lining umbilical can be secured to prevent catenary sag in the umbilical. Catenary sag will contribute to minor variation in lining thickness.
Once the lining umbilical is in the lining start pit, the spray head is attached by workers located in the pit. All in pit workers should have all appropriate Protective Personnel Equipment (PPE). With all resin lines, in the closed position, the head is checked for proper spin RPM (±10,000) then shut down. Only after spin verification, the spray head is brought back up to full speed and then the two resin lines are opened. Resin spray should be contained in a pail. The pail is then used to contain the spray until the spray head is in the pipe.
The umbilical and spray head are pulled back through the pipe at a controlled and specified rate to apply the lining at a uniform thickness up to 3 mm for pipes less than 12in and 3.5mm for pipes greater than 12in.
The umbilical pull-back rate depends on the flow rate of the material, lining thickness, and pipe diameter. Throughout the lining process the resin mix ratio, temperature, flow rate, lining thickness, hose speed and length lined should be continuously monitored.
At the end of the lining process and prior to the spray head assembly exiting the pipe, workers in the pit with PPE, should guide the spray head out of the pipe and into a pail, to control the spray.
The lining rig utilizes flow meters to monitor the volumetric accuracy of material delivery during the lining process. A Quality Assurance procedure, to confirm that the lining rig pumping and monitoring system are both working correctly, is undertaken before every lining. This is a manual weight checking procedure of the dispensed material components taken from the rig weight checking station. The lining rig shall be set in long recirculation mode, pumping at the flow rate for which the lining is to be performed. A minimum of three weight checks shall be taken at time intervals of at least three minutes apart. A minimum of 500g of base component shall be collected for each weight check. The results of these manual weight checks shall be entered into the sequential control lining rig computer system. The last weight check should be undertaken, not more than one hour before lining is to commence. Otherwise, the weight check process should be repeated.
The mix ratio is calculated as follows: [Weight of Activator]/[Weight of Base] x 100. The results must all be within +/-5% of the Resiline published mix ratio by weight (100:72.5) If any of the weight checks do not comply with this quality check, weight checking should be repeated until three consecutive results meet this requirement.
Lining should not commence until the accuracy of mix ratio delivery of the lining rig has been confirmed through the weight check procedure.
An umbilical is used to transfer material to the spray head. It is critical to maintain tension on the umbilical between the retrieval end (near the rig) of the pipe and the umbilical drum on the rig to help maintain a uniform spray lining throughout the length of the pipe. Following the weight check, the lining rig umbilical needs to be winched through the pipe to be lined. This is accomplished after the CCTV camera tether pulls the winch cable from the rig retrieval pit to the lining start pit.
The lining rig needs to be located to pull the lining rig umbilical straight and in line with the pipe to be lined. Rollers should be installed, to ensure the smooth pulling of the lining umbilical. A supporting structure may need to be installed, so that pulleys supporting the lining umbilical can be secured to prevent catenary sag in the umbilical. Catenary sag will contribute to variation in lining thickness.
Once the lining umbilical is in the lining start pit, the spray head is attached by workers located in the pit. All in pit workers should have all appropriate Protective Personnel Equipment (PPE). With all resin lines, in the closed position, the head is checked for proper spin RPM (±10,000) then shut down. Only after spin verification, the spray head is brought back up to full speed and then the two resin lines are opened. Resin spray should be contained in a pail. The pail is then used to contain the spray until the spray head is in the pipe.
The umbilical and spray head are pulled back through the pipe at a controlled and specified rate to apply the lining at a uniform thickness up to 3 mm for pipes less than 12in and 3.5mm for pipes greater than 12in.
The umbilical pull-back rate depends on the flow rate of the material, lining thickness, and pipe diameter. Throughout the lining process the resin mix ratio, temperature, flow rate, lining thickness, hose speed and length lined should be continuously monitored.
At the end of the lining process and prior to the spray head assembly exiting the pipe, workers in the pit with PPE, should guide the spray head out of the pipe and into a pail, to control the spray.
A CCTV inspection of the lining can commence 15 minutes after lining completion.
For multiple lining pass applications, the lining process and CCTV inspection noted are repeated until the design thickness is achieved or a maximum of 14 mm is applied.
After each lining application, a CCTV inspection is completed to record and note items such as: 1) the condition of the lining around services; and 2) lining defects such as pin holes and water intrusion.
During each spray pass, Resiline 320 material can build up on protruding services and can potentially restrict the openings of the service connection. It may also completely cover and block service connections.
The service connection size, circumferential location, protrusion depth into the distribution pipe wall, and the thickness of applied lining amount of material, will affect the amount of lining build up and potential service restriction.
If the service is restricted, a robotic cutter can be used to open the service. Care must be used not to damage the service, lining, and pipe when drilling out a service. After cutting the lining material away, service back flushing, may be required to remove the debris from the connection. The pipe may also need to be flushed to remove debris.
A final pipe CCTV inspection, CCTV V3, should be completed and recorded.
Disinfection of water pipes, after lining, is a common industry practice. The lining shall be allowed to fully cure for a minimum of 60 minutes before disinfection and flushing. The pipe shall be secured by capping the ends to prevent contamination.
When selecting a specific disinfection method, SIPP Americas advises to contact the local municipality, utility department or government agency with jurisdiction over the project.
For fast Return to Service SIPP Americas recommend using the Schur BHP Steri-Klenze system. This system disinfects the new Resiline 320 liner by saturating the pipe liner with 200 ppm Sodium Hypopchlorite. Throughout the disinfection process the data is continuously collected and recorded i.e. flow rate, disinfection concentration, etc.
Other main disinfection methods include ozonation, tablet method, continuous feed method, and slug methods. Some of these methods require the use of chlorine, in quantities ranging from 25 mg/L to 500 mg/L, and contact times ranging from 24 hours to 72 hours. AWWA C-651 provides further guidance on disinfection of watermains.
End Seals
It is recommended best practice to end seal any pipes that are cut after the lining is installed due to the localized force applied to the lining at the cut edge. Only Resimac qualified end sealing solutions shall be used to seal ends of a lined pipe. The end seal material shall be locally potable water contact certified, and end seal approved for use with Resiline 320.
Following the application, a visual inspection shall be made of the applied end sealer, after it has cured to help ensure there is no crack or break in the applied Resiline 320. If any crack or gaps are visible, in the applied end seal, the area extending beyond the crack shall be abraded to complete a fresh application of the approved end seal.
Pipe Connection
NSF/ANSI 61 approved mechanical fittings for HDPE or ductile iron pipes may be used to reconnect entry and exit points of a lined pipe. Care should be taken to properly support the lined protruding pipe sections during reinstatement. Any removed service connection should be replaced with fittings that have a shoulder support attached to the main.
Valves and Appurtenances
All valves should be inspected upon reconnection to ensure proper working condition. All valves and appurtenances should be installed and rigidly supported. Any damaged items must be repaired or replaced before they are reinstalled. Hydrants should be connected to pipe at the original location, unless specified otherwise. The outside of the hydrant, above the finished ground line, should be thoroughly cleaned to remove all dirt, debris, and dust.
SIPP Americas LLC is a leading applicator of specialized Polyurea Protective Industrial Coatings throughout the United States, Canada and Mexico.
Focusing on the needs and priorities of our customers, Induracoat offers industry leading “Green” solutions through its Polyurea spray coating systems.
Website Designed and Maintained by Encompass Business Solutions
