pay attention to these points, "second liter" CIPP local repair quality
In the case of local cracks, leakage and damage of the pipeline, when emergency repair is needed due to local damage of the pipeline, CIPP local repair technology can be used to repair the pipeline. Scope of application: groundwater influx at leakage places such as pipe joints and pipe walls; Disconnection, breakage, cracking and dislocation; Mechanical wear; Corrosion. Applicable pipe diameter: 100mm-1350mm. The use of this technology to repair the damaged point can form a high-strength new pipe combined with the old pipe, wear resistance, corrosion resistance, normal can maintain a life of more than 30 years. However, some local repairs can only be maintained for a few years, and some are even shorter. According to the long-term pipeline repair experience, I sum up some possibilities and solutions, I hope to help you in the future construction.
1. Pipeline pretreatment
Due to the unclean pretreatment of the pipeline, some sediment, grease and other impurities on the repair site are still left on the pipe wall. After repair, the lining pipe can only stick to these impurities and cannot stick to the pipe wall, resulting in shortened repair life. Solution: Clean the pipeline a little before repair, and choose a special nozzle for special working conditions. For example, multi-function rotating nozzle can be used for more grease on pipe wall; Pipe bottom cleaning machine can be used for more sediment at the bottom of large diameter pipeline; Cement slurry remover can be used for more cement slurry. Due to the complexity of pipeline pretreatment, this article will not give examples one by one, and will find time to discuss with you later.
Multi-function rotating nozzle
Tube bottom cleaning machine
cement slurry remover
2. Positioning of repair points
Due to the inaccurate positioning of the damaged point, the repair material cannot completely cover the damaged point or the contact surface with the good pipeline is small, and the adhesion is not firm, resulting in shortened repair life. Solution: 1. Small diameter pipeline (below DN600) shall be positioned by CCTV, and large diameter pipeline (above DN600) shall be positioned manually. 2. Try to shorten the positioning length (the longer the repair distance, the less accurate the positioning), and the repair airbag enters from the wellhead near the repair point. 3. The larger point of rupture can be repaired several times in succession to ensure the effective fit of the repair material and the pipe wall.
3. Use of repair materials
the use of inferior repair resin or incorrect use of repair resin will cause insufficient adhesion between the material and the pipe wall, resulting in shortened repair life. solution: 1. the use of quality assurance of repair resin. The curing time cannot be adjusted by adjusting the ratio of curing agent to resin. Different types of resin should be selected for different temperatures.
the use of poor quality glass fiber cloth or glass fiber cloth is not used correctly, the material strength is not enough to shorten the repair life. solution: 1. the use of double layer structure, woven tightly fiberglass cloth, repair after higher strength, better effect. 2. When repairing pipes with different pipe diameters, the number of layers of glass fiber cloth should be different. According to German technology: DN100-450, glass fiber cloth should be 3 layers; DN500-600, glass fiber cloth should be 4 layers; DN675-750, glass fiber cloth should be 5 layers; More than DN800, glass fiber cloth should be 6 layers.
Saikang Repair Resin
double-layer structure fiberglass cloth
4. Use of repair airbag
the use of poor quality repair airbags or the replacement of repair airbags with occluding airbags, insufficient inflation pressure and insufficient pressure holding time, the adhesion between the material and the pipe wall will be insufficient, resulting in shortened repair life. Solution: Use a good quality repair airbag, inflate to reach the rated inflation pressure, and different types of resins have different holding times at different temperatures.
Cheney Fixes Air Bag
Repaired Airbag
, I hope you will pay more attention to the above points in the future construction process, and you will definitely be able to "improve" the local repair quality of CIPP in seconds.
