Brinks Services - pipelining with CuraFlo

CuraFlo™ is expanding to meet a growing need:

Historically CuraFlo™ Technologies Inc. and its' family of dealers have restored and epoxy lined pipe systems with 1/2" to 4" inside diameters.

Effective March, 2004 CuraFlo™ Technologies through Brinks Services can provide you full on-site restoration and epoxy lining for all types of pipe systems including potable water piping and drain systems with 3" to 24" inside diameters.

This division of CuraFlo™ Technologies Inc. will be known as CT324.

A detailed overview of our CT324 program can be found in this section of our website or you can contact us for direct information or assistance on reviewing your specific project needs.

The CT324 Large Diameter In-Situ Pipe Lining Process In Summary:

The following is a brief outline and description of the basic sequence of procedures for the in-situ lining of pipelines. Due to the vast array of piping types and pipe locations that can be relined using the CT324 System, certain processes contained in this summary may be omitted or altered dependant on the individual project undertaken.

1. Pipe location. Any buried pipe to be rehabilitated must be located using a combination of the following: Plans, Underground locating equipment, above ground fittings (Valves, Fire Hydrants etc.) All "other" utilities must also be located and marked prior to excavation. Non buried pipes must be located using whatever methods are available.

2. Bypass Installation. Certain projects require the use of an above ground bypass system. This system should supply potable water to each consumer and if required, have the approval of the local fire department to ensure adequate fire protection.

3. Pipe isolation. The piping system to be rehabilitated should be isolated. This is done by closing the appropriate isolating valves within the system so as to shut off water to the appropriate pipes, while maintaining supplies to piping systems not included in the "work."

4. Excavation. Excavations (access points) should be located at pre-determined locations, preferably at existing fittings (valves, tees, fire hydrants, bends, etc.) and should be of a suitable size to allow safe access to the pipe. All excavations shall conform to all local, state and OSHA safety requirements.

5. Cleaning. Pipe sections or fittings should be removed from each access point. The internal surface should then be cleaned using the appropriate cleaning method. The most common methods of cleaning pipes in situ are; power boring and drag scrapping. There are several other methods of cleaning including, but not limited to: sand blasting, pigging (aggressive and non aggressive), high pressure jetting, pressure scrapping, wire brushing and chemical cleaning.

Power Boring: This process utilizes purpose built equipment that introduces high tensile steel rods, that are coupled together, into the pipe while rotating them. An attachment is fixed to the leading rod that has "flail arms" attached to it. The combination of rotation, forward movement and a flow of water traveling in the opposite direction to the rods and flails, allows the flail arms to remove the tuberculation from the interior pipe surface, leaving it smooth and even. Once enough rods have been coupled together and the total pipe section has been cleaned the rods are removed and the remaining water and cleaning debris are removed from the pipe by blowing foam, cylindrical swabbs through the pipe length using compressed air. Once the pipe is clean and dry it is ready to be inspected.
Drag Scrapping: This process utilizes a "scrapping tool." This tool is designed to literally scrape the tuberculation from the interior surface of the pipe. The tool is pulled through the pipe in each direction, with the use of steel cables, until the pipe surface is clean and smooth. The remaining water and debris are then removed by pulling rubber plungers/disks through the pipe in the same manner as the scrapping tool. It is recommended that foam swabbs are then passed through the pipe to remove any fine particles that may still be present in joints and etc. Once the pipe is clean and dry it is ready to be inspected.

6. Pre-Lining Inspection. Prior to lining, the cleaned pipe must be inspected using a CCTV system. The purpose of the inspection is to determine the effectiveness of the cleaning, and highlight any potential problems, such as: passing or leaking valves or service connections, standing water, bends, over poured lead joints, buried valves or structural failures.

If the CCTV inspection does not indicate any problems the lining process can be undertaken. If problems are identified they should be dealt with at this time, the pipe should be inspected again to verify rectification, the lining process can then be undertaken.

7. Lining. The lining process is undertaken using purpose built equipment. The equipment is designed to store, heat, pump, monitor, mix and spray polymeric formulations. The equipment and process has various stages, which when combined complete the lining process.

Equipment description:

The self contained equipment, "Lining Rig," is trailer mounted and has separate storage tanks for each component, activator (A) and base (B), of the 2 part polymeric material, the tanks are jacketed and a hot water system fills the jacket heating the material inside, two pumps, transfer each component individually to the main metering pump.

This is a positive displacement pump, ensuring the correct volume of each component is pumped into the lining hoses with each stroke. Prior to the material entering the lining hoses each component passes through a flow meter. The flow meters send the information received to the on board computer/controller.

This controller calculates the individual volumes to give a % ratio between the two. This also ensures the metering pump is functioning correctly. This process ensures the correct mix ratio is being produced by the equipment.

The lining hoses contain 6 individual hoses within a larger hose sheath, 1 x A, 1 x B, 1 x air and 3 x water. As with the tanks the lining hoses are heated, two small hoses carry hot water to the end of the hose sheath and one is used for the return of the water. The water is then re-heated and the cycle continues.

This system ensures the material in the hoses is the same temperature as the material in the lining rig tanks and within the temperature range specified by the material manufacturer. The hoses for A & B carry the polymeric materials and the air hose is used to supply air to the application spray head. Components A & B remain separate throughout the process until the application spray head is attached.

At the far end of the lining hoses a mixer block and static mixer hose are attached. The mixer block attaches to the end of the hoses carrying A & B, the static mixer hose attaches to the other end of the mixer block. This static mixer is a short section of hose that contains several helix’s.

As the material passes through the hose and helix’s it is mixed. The application spray head is attached to the end of the static mixer hose. The spray head has a small air motor inside, this drives a "cone" at its end. The mixed material passes through the centre of the spray head, enters the cone and is centrifugally expelled from it. The centrifugal motion of the application head "cone" expelling the material ensures an even coating as the hoses and application head are pulled through the pipe. A skid configuration surrounding the application spray head ensures the it is located centrally throughout the lining process.

All critical functions of the process are controlled/monitored by the computer/controller. This computer/controller gathers data from various sensors within the system and displays it on a screen.

Should the controller receive data outside of the operating parameters of either the equipment or material an alarm will sound giving the operator time to rectify the problem. If no action is taken, the problem persists or the controller indicates the problem is outside of the pre determined tolerances it will shut the equipment off, preventing an out of tolerance lining being applied.

Lining Process Description:

The material in the equipment is heated and pumped/re-circulated from the storage tanks to the lining hoses and back to the tanks. Thus ensuring stable temperatures and pressures throughout the system. The controller monitors the process, giving the operator the ability to determine the appropriate time to commence the lining application.

Once the temperatures and pressures have stabilized, (depending on the material and application requirements), a series of three manual weight checks are performed. These checks give a % calculation between the two components by weight as opposed to volume given by the monitoring system. (These checks are used as a back up of the information given by the monitoring system.) Once three consecutive weight checks have passed the controller will shut the pumping system off.

The lining hoses will then be pulled through the pipe to the opposite end of the lining run. Once they are at the far access opening the mixer block, static mixer hose and application spray head are attached. The pumping system is then turned back on.

As the mixed material is expelled from the application spray head into a bucket it is monitored by the person that installed the application head for color. Once the color has stabilized a sample of the mixed material is taken by spraying it on to a test card.

The lining hoses are then winched back into the pipe by the lining rig, at a controlled rate that is linked to the flow rate of the material, to coat the pipe with the desired coating thickness. The process continues until the application spray head exits the pipe at the lining equipment access opening. The pipe is inspected at both ends and then sealed to allow the lining material to cure.

8. Post Lining Inspection. Following the required cure time for the applied lining, the coating must be inspected using a CCTV system. The purpose of the inspection is to verify the quality of the applied lining and determine if any problems are present. Any problems identified should be rectified at this time.

9. Reconnection. Once the lining has been accepted the pipe work can be reconnected, disinfected (if required) and returned to service.

To visit the CuraFlo website for more information, please click here.