The process involves inserting a “engineered liner”, which is an intricate blend of glass fibre and polypropylene filaments, into the pipe to be lined. A heating pig is then passed through the woven engineered liner which heats the material, using hot air, to above the melt temperature of the polypropylene material (i.e. above 180°C). The molten mixture of glass fibres and polypropylene is then consolidated against the pipe wall by a pressurised silicone rubber inversion hose.
Upon contact with the pipe wall the materials cool down to form a thin walled structural glass fibre reinforced polypropylene liner. The process is currently designed to be capable of lining pipes between 4” and 12” diameter. Expansion of this production range is currently under consideration.
The latest equipment design consists of the following:
- A motorised and process controlled 3Bar inversion drum capable of deploying a 70M silicone rubber inversion bag at a precise rate and under controlled pressure.
- Reinforced silicone rubber inversion bags up to 70M long capable of operating up to 3 Bar and process temperatures up to 215 Deg C. The silicone rubber bags being low friction and robust.
- A heating PIG capable of lining pipes with diameters of 8” and 9”. The PIGs were designed with 21 KW heaters coupled with technology to mix and diffuse the hot air efficiently.
- A proprietary process control unit which controls the temperature of the hot air exiting the heating PIG. The process control unit monitors and records all the key process data, namely, temperature and pressure as a function of time.
- A 100M long flexible twin hose umbilical capable of providing the power and compressed air to the heating PIG. The umbilical is light, robust and flexible enough to enable it to navigate around tight bends, inlets and culverts.