Tecnologia de construção de tubulações de abastecimento de água!

The quality of the water supply pipeline system directly affects the overall use function and safety performance of the building. As an important part of the building infrastructure, the water supply pipeline must not only ensure the stability and safety of water supply, but also meet the requirements of energy saving, environmental protection, durability and beauty. With the continuous emergence of new pipe materials and the continuous optimization of construction technology, the construction technology of building water supply pipelines is developing in the direction of high efficiency, environmental protection and intelligence.

The main materials, finished products, semi-finished products, accessories, appliances and equipment must have Chinese quality certification documents, and the specifications, models and performance test reports should comply with national technical standards or design requirements. The materials involved in the domestic water supply system should meet the health and safety standards. Inspection and acceptance should be carried out when entering the site, and verified and confirmed by the supervising engineer.

For example: the flexible joints of the domestic water supply system generally use stainless steel flexible joints instead of rubber flexible joints, because the latter are difficult to meet the drinking water hygiene standards.

Before the valve is installed, strength and tightness tests should be carried out. The test should be conducted on 10% of the quantity of each batch (same brand, same model, same specification), and not less than 1. For closed-circuit valves installed on the main pipe for cutting off, strength and tightness tests should be carried out one by one (100%)

The strength test pressure of the valve is 1.5 times the nominal pressure; the tightness test pressure is 1.1 times the nominal pressure; the test pressure should remain unchanged during the test duration, and there should be no leakage in the shell packing and valve disc sealing surface. The duration of the tightness and strength test of the valve should not be less than the provisions in the following table

Valve tightness and strength test duration

The sliding bracket should be flexible, and there should be a gap of 3~5mm between the sliding bracket and the two sides of the slideway. The longitudinal movement should meet the design requirements.

Hangers and hangers for pipes without thermal expansion should be installed vertically. Hangers and hangers for pipes with thermal expansion should be offset in the opposite direction of thermal expansion.

The spacing between brackets for vertical or horizontal installation of plastic pipes and composite pipes should meet the requirements of the specifications. For pipe brackets made of metal, non-metallic pads or sleeves should be added between the pipe and the bracket.

The steel pipe should be no less than 3.5 times the outer diameter of the pipe when hot-bending and no less than 4 times the outer diameter of the pipe when cold-bending;

The welded elbow should be no less than 1.5 times the outer diameter of the pipe; the stamped elbow should be no less than the outer diameter of the pipe.

Pipeline installation should generally be carried out in accordance with the principle of installing the main pipe first and then the branch pipe, the upper part first and then the lower part, and the inside first and then the outside. For pipes of different materials, steel pipes should be installed first and plastic pipes should be installed later.

When hot and cold water pipes are installed in parallel, the hot water pipe should be above the cold water pipe. When installed vertically, the hot water pipe should be on the left side of the cold water pipe.

The horizontal clearance between the water supply inlet pipe and the drainage outlet pipe shall not be less than 1m. When indoor water supply and drainage pipes are laid in parallel, the minimum horizontal clearance between the two pipes shall not be less than 0.5m; when laid crosswise, the vertical clearance shall not be less than 0.15m. The water supply pipe should be laid on the drainage pipe. If the water supply pipe must be laid under the drainage pipe, the water supply pipe should be sleeved and its length shall not be less than 3 times the diameter of the drainage pipe. (4) The horizontal water supply pipe should have a slope of 2‰-5‰ towards the drainage device.

The water meter should be installed in a place that is easy to inspect and is not exposed to sunlight, pollution or freezing. When installing a propeller water meter, there should be a straight pipe section in front of the meter and the valve that is not less than 8 times the diameter of the water meter interface.

When the pipe passes through the wall and floor, a metal or plastic sleeve should be installed. The top of the sleeve installed in the floor should be 20mm higher than the decorative floor; the top of the sleeve installed in the bathroom and kitchen should be 50mm higher than the decorative floor, and the bottom should be flush with the bottom of the floor; the ends of the sleeve installed in the wall should be flush with the decorative surface, and the gap between the sleeve passing through the floor and the pipe should be filled with flame-retardant dense materials and waterproof grease, and the end surface should be smooth. The gap between the wall sleeve and the pipe should be filled with flame-retardant dense materials, and the end surface should be smooth. The interface of the pipe shall not be set in the sleeve.

Indoor directly buried water supply pipes (except plastic pipes and composite pipes) should be treated with anti-corrosion. The material and structure of the anti-corrosion layer of buried pipes should meet the design requirements.

The main anti-corrosion method for pipes is painting. When applying paint manually, the thickness of the paint layer should be uniform. When applying multiple coats, the second coat can only be applied after the previous coat is dry.

The pipes of the building direct drinking water system must use pipe fittings that are compatible with the pipes. The materials and equipment involved in the direct drinking water system must meet the hygienic and safety requirements of drinking water.

The pipes of the building direct drinking water system should be made of thin-walled stainless steel pipes, copper pipes or other high-quality water supply plastic pipes and high-quality steel-plastic composite pipes that meet food grade requirements. The boiling water pipes should use metal pipes with an operating temperature greater than 100°C.

The drinking fountains should be made of stainless steel and copper chrome-plated products, and their surfaces should be smooth and easy to clean.

The bottom layer of the trench should be the original soil layer or compacted backfill soil. The bottom of the trench should be flat and the slope should be smooth. There should be no sharp objects, boulders, etc.

If the trench base is rock, boulders that are difficult to remove, or a gravel layer, the bottom of the trench should be dug down 100-200mm, filled with fine sand or fine soil with a particle size of no more than 5mm, and compacted to the trench bottom elevation before laying the pipeline.

When water supply pipes and sewage pipes are laid in parallel at different elevations and their vertical spacing is within 500mm, the horizontal spacing of the pipe wall of water supply pipes with a diameter less than or equal to 200mm shall not be less than 1.5m; for pipes with a diameter greater than 200mm, it shall not be less than 3m.

For the installation of pipes in various well chambers of the water supply system, if there is no design requirement, the distance from the wall to the flange or socket shall not be less than 250mm when the pipe diameter is less than or equal to 450mm; and shall not be less than 350mm when the pipe diameter is greater than 450mm.

The pipes and fittings of the grey water supply pipeline should be corrosion-resistant.

The high-level water tank for recycled water should be installed in a different room from the high-level water tank for domestic use. If conditions do not permit and they must be installed in the same room, the net distance from the high-level water tank for domestic use should be greater than 2m.

Water intake nozzles shall not be installed on the reclaimed water supply pipeline. Closed equipment and appliances should be used for toilet flushing. Wall-mounted or underground water taps should be used for landscaping, wine pouring, and car washing.

It is strictly forbidden to connect the reclaimed water supply pipeline with the domestic drinking water supply pipeline, and the following measures should be taken: the outer wall of the reclaimed water pipeline should be painted with a light green mark; the reclaimed water tank (box), valve, water meter and water tap should all have the “reclaimed water” mark.

The reclaimed water pipeline should not be concealed in the wall and floor. If it must be concealed in the wall groove, there must be obvious and non-falling marks on the pipeline.

When the reclaimed water pipeline is buried parallel to the domestic drinking water pipeline and the drainage pipeline, the horizontal net distance shall not be less than 0.5m; when cross-buried, the reclaimed water pipeline should be located below the domestic drinking water pipeline and above the drainage pipeline, and the net distance shall not be less than 0.15m.