Large diameter municipal sewer trenchless No-Dig rehab by CIPP UV technology

Preparation of UV curing construction instructions:

The drainage pipeline is gravity flow. The upstream (the front section in the downstream direction) and downstream (the rear section in the downstream direction) of the pipeline shall be determined in advance, so as to determine the sequence of repairing dragging materials.

If the site space allows, it is suggested to drag the bottom film and materials in the following order: starting from the upstream direction and dragging along the downstream direction.

1. pretreatment:

Ventilation, water stop, pumping, dredging, and cleaning. Ensure that there is no ponding, water leakage, foreign matter, serious deformation or dislocation, and other defects inside the pipeline.

2. robot CCTV inspection to determine whether it can be repaired

3. pull the bottom film with a robot: (use braided rope, do not replace the rope at will, otherwise the material or membrane will rotate in the pipe)

The connection buckle between the rope head and the bottom membrane shall be firmly fastened, and another rope for pulling materials shall be put on the upper end of the bottom membrane (if a winch is used, it shall be a steel wire rope). During the membrane pulling process, ensure that the materials and ropes are not mixed with the rotation of the bottom membrane.

For long-distance materials with large pipe diameters, soapy water can be added to the bottom film to reduce the friction when the material is dragged.