Step by step process:
1, check each section of conduit has no obvious holes, check each section of conduit seal ring integrity, all conduit production should strive to be strong, the inner wall should be smooth, straight, clean and no local defects in the bump. The inner diameter of each section of conduit should be the same size (the inner diameter of the conduit used in field construction is 260mm), the deviation is not more than ± 2mm. the missing or worn out conduit found on the scene, it should be removed in time to replace or add, and in the steel cable groove coated with appropriate grease.
2, choose the site, so that the conduit on the ground level docking, docking on each section of the conduit according to the sequence of numbering (conduit first and last docking order of 4.0m / section + 2.7m / section * 15 sections = 44.5m) first of all, the conduit first and last with a sealing fasteners connected. The conduit can be pre-assembled in sections next to the drilling hole, and then assembled section by section when lifting and placing. It should be carefully inspected when assembled in sections.
3, the two ends of the conduit installation of closed device, closed device using both pressure sets. Installation so that the two holes are located directly above the pipe, in order to inject water from the air overflow.
4, the installation of the water pipe to the conduit injection of water, water injection to the other end of the pipe out of the water to stop, and should ensure that the conduit flushing up to 70% or more, before stopping.
Expanded Information:
The conduit pressure water tightness test should be carried out using the method of filling the tube with water and pressure, and it is strictly prohibited to carry out the conduit water tightness test inspection using the method of pressurizing the tube with gas. Check the conduit joints overflow situation, the overflow of water to make a record, the conduit rolled 180, pressurized again, maintain pressure for 15 minutes, check the situation to make a record. After 15 minutes without water leakage is qualified.
The purpose of the test is to check whether the conduit has water leakage, air leakage phenomenon, to ensure the quality of filling concrete. Test conduit wall and weld compressive strength to meet the construction requirements.
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