National standard GB/T19472.2 carat tube acceptance construction specification

Pre-construction site verification requirements

During the entry stage, it is necessary to strictly check the parameters of the carat tube against the GB/T19472.2 standard, focusing on whether the product ring stiffness, nominal diameter, wall thickness and other indicators meet the engineering design requirements, and check the appearance of the pipe wall one by one, without cracks, depressions, burrs and other obvious defects. At the same time, the same batch of product inspection reports and qualification certificates are required, and different batches and different specifications of products are sampled for inspection in proportion to prevent substandard products from entering the construction site.

Code of operation for on-site construction

The trench excavation needs to be combined with the geological conditions of the construction area and the distribution of underground pipelines to determine the excavation depth and slope. The pipe foundation is laid with a gravel cushion with a thickness of not less than 100mm. The cushion needs to be flat and tamped to avoid local protrusion and damage to the pipe wall. Flexible sling is required for hoisting operations. It is strictly forbidden to use wire ropes to directly bind the pipe wall to avoid scratches and force cracking of the pipe. The interface connection is preferentially made of electrofusion or heat shrinkable tape process. Before connecting, the nozzle impurities need to be cleaned up. After alignment, the welding operation is performed according to the standard parameters. After the welding is completed, let it stand and cool for more than 30 The backfill operation requires layered tamping. The thickness of each layer of backfill should not exceed 200mm. Sharp objects such as large stones and concrete blocks should not be mixed. Manual tamping should be used within 500mm of the top of the pipe to avoid deformation caused by mechanical rolling.

Completion Acceptance Core Criteria

Completion acceptance needs to strictly follow GB/T19472.2 and municipal pipeline engineering acceptance requirements. First, check the full set of construction data, including approach verification records, construction logs, interface welding inspection records, backfill compactness test reports, etc., and then carry out the closed water test. When the test head meets the design requirements, the 24-hour leakage shall not exceed the threshold specified in the standard. The appearance inspection needs to confirm that there is no obvious deformation of the pipe wall, the radial deformation rate shall not exceed 3%, the density of each layer of the trench backfill meets the design requirements, and all the indicators can be tested before the completion acceptance can be completed and delivered for use.

Strict implementation of the above specifications can effectively reduce the risk of leakage and deformation of the carat pipe project, prolong the service life of the pipeline, give full play to its corrosion resistance, good liquidity, and light weight performance advantages, and adapt to various engineering scenarios such as municipal drainage, sewage, and sponge city construction.