How to repair if the middle of the HDEP double-wall corrugated pipe is cut?

How to repair if the middle of the HDEP double-wall corrugated pipe is cut?

1. After the HDPE double-wall corrugated pipe is laid, the wall of the pipe is partially damaged due to unexpected factors. When the area of the damaged part or the length and width of the crack does not exceed the regulations, paste repair measures can be taken.

2. When the diameter or side length of the partially damaged hole of the HDPE double-wall corrugated pipe wall is not more than 20mm, a circular plate with a diameter of not less than 100mm and the same material as the pipe can be pasted with a PVC plastic bonding solvent on the outside.

3. When the local damage of the pipe wall is 20-100mm, the PVC plastic adhesive solvent can be used to paste a circular plate not less than the maximum size of the hole plus 100mm with the same material as the pipe.

4. There are local cracks on the pipe wall. When the length of the crack is not greater than 1/12 of the circumference of the pipe, a plate with a length greater than the crack length plus 100mm and a width of not less than 60mm and the same material as the pipe can be pasted at the crack. Both ends of the plate should be Cut into circular arcs.

5. Before repairing, the water in the pipe should be removed first, and the damaged part of the pipe wall should be trimmed with a scraper, and cleaned with water. For special-shaped wall pipes, the ribs in the patching range must be removed, and then smoothed with sandpaper or a file.

6. Before bonding, the base surface of the bonding part should be brushed with cyclohexanone, and the bonding solvent should be brushed as soon as possible after drying. The plate used for external sticking should be an arc plate cut from the corresponding part of the pipe with the same diameter. The inner side of the externally affixed sheet must also be cleaned first, and then the base surface is painted with cyclohexanone, and then the bonding solvent is painted.

7. For holes not larger than 20mm, after the pasting is completed, it can be wrapped and fixed with geotextile, and the soil can be returned after curing for 24 hours; for holes and cracks larger than 20mm, after the pasting is completed, it can be wrapped and fixed with lead wire.

8. After the repair of the pipeline is completed, the hollowed out part of the bottom of the pipe must be backfilled and compacted with coarse sand according to the requirements of the supporting angle.

9. To take repair measures for damaged pipelines, the construction unit should obtain the consent of the management unit and on-site supervisors in advance; for the damage at the bottom of the pipeline, it should also obtain the consent of the design unit before implementation.

10. If using electrode welding repair or chemical water-stopping agent and other leak-stopping repair measures, it can only be implemented after obtaining the approval of the management unit.

11. When the size of the damaged part of the pipeline exceeds the provisions of the above provisions, the damaged pipe section should be replaced. When there is no special connecting pipe fittings between the replaced PE double-wall corrugated pipe and the laid pipes, masonry inspection wells or connecting wells can be connected.