Technical specification for building drainage hard polyvinyl chloride pipeline engineering (1)

1 General
1.0.1 In order to achieve advanced technology, economic rationality, safety and applicability, and ensure quality in the design, construction, and acceptance of building drainage hard polyvinyl chloride pipeline engineering, this regulation is formulated.
1.0.2 This regulation is applicable to the design, construction, and acceptance of domestic drainage pipelines in industrial and civil buildings with a continuous emission temperature not exceeding 40 ℃ and an instantaneous emission temperature not exceeding 80 ℃, with a building height not exceeding 100m.
1.0.3 The pipes and fittings of rigid polyvinyl chloride pipes for building drainage shall comply with the requirements of the current national standards “Rigid polyvinyl chloride pipes for building drainage” (GB/T5836.1), “Foamed rigid polyvinyl chloride pipes with core layer for drainage” (GB/Tl6800), and “Rigid polyvinyl chloride pipes for building drainage” (GB/T5836.2). The design, construction, and acceptance of building drainage hard polyvinyl chloride pipeline engineering should not only comply with this regulation, but also comply with the current national standards.
2 Terminology
2.0.1 Fire stopping sleeves
A pipe made of refractory materials and flame retardants that is sheathed on the outer wall of a rigid polyvinyl chloride pipe to prevent the spread of fire along the pipe’s penetration.
2.0.2 Firestops Collar is a sleeve made of flame retardant expansion agent and placed on the outer wall of rigid polyvinyl chloride pipes. During a fire, the flame retardant expands and compresses the PVC pipeline, blocking it and preventing the spread of the fire.
2.0.3 H Pipe H Pipe is a pipe fitting used to connect the ventilation riser and drainage riser, serving as a combination of ventilation pipes.
2.0.4 Pipe alley A narrow, unobstructed space constructed for the layout of pipelines.
2.0.5 Air admission valve is a one-way air valve that can automatically replenish air and balance the pressure inside the drainage pipeline.
3 Design 3.1 Pipeline Layout
3.1.1 The exposed or concealed layout of pipelines should be determined based on the nature of the building, usage requirements, and building layout.
3.1.2 In areas with an average minimum temperature of 0 ℃ or above in the coldest month and an extreme minimum temperature of -5 ℃ or above, pipelines can be installed on external walls.
3.1.3 The layout of indoor drainage 3d scanning to detect pipeline leaks in high-rise buildings should comply with the following regulations:
1. The riser should be concealed in the pipeline well or hole.
When the riser is exposed and its diameter is greater than or equal to ll0mm, measures should be taken to prevent fire penetration at the location where the riser crosses the floor.
When the exposed drainage horizontal branch pipe with a diameter greater than or equal to 110mm is connected to the vertical pipe in the pipe well or pipe gallery, measures should be taken to prevent fire penetration at the crossing of the pipe well or pipe gallery wall.
3.1.4 Horizontal main pipes should not pass through fire compartments

3.1.11 The drainage riser should be equipped with a top extending vent pipe, and a vent cap should be installed at the top. When unconditionally setting the top extension ventilation silicon carbide ceramic pipe with internal thread, it is advisable to set up a makeup valve.
3.1.12 The height of the protruding ventilation pipe above the roof (including insulation layer) shall not be less than 0.3m and shall be greater than the maximum snow thickness. On roofs with frequent human activity, the ventilation pipe should not protrude less than 2 meters from the roof.
3.1.13 The diameter of the overhead ventilation pipe should not be smaller than the diameter of the drainage riser. In areas where the average temperature in the coldest month is below -13 ℃, when the diameter of the overhead ventilation pipe is less than or equal to 125mm, it is advisable to increase the pipe diameter by one size from 0.3m below the indoor ceiling, and the minimum pipe diameter should not be less than 110mm.
3.1.14 The design of the ventilation pipe should comply with the following regulations:
The minimum diameter of the ventilation pipe should be determined according to Table 3.1.14.
When the length of the ventilation riser is greater than 50m, its diameter should be the same as the sewage riser.
When two or more sewage vertical pipes are connected to one ventilation vertical pipe at the same time, the maximum sewage vertical pipe should be used
Table 3.1.14 determines the diameter of the ventilation riser, and its diameter should not be smaller than the diameter of any other sewage riser.
The diameter of the ventilation pipe should not be smaller than the diameter of the ventilation riser.
3.1.15 When using an H pipe, it can be separated by layers. The connection point between the H pipe and the ventilation riser should be 0.15m higher than the upper edge of the sanitary ware.
3.1.16 When the domestic sewage vertical pipe and the domestic sewage vertical pipe share a ventilation vertical pipe, and the H pipe is used as the connecting pipe fitting, the H pipe can be connected to the domestic sewage vertical pipe and the wastewater vertical pipe in staggered layers, but a combined ventilation pipe should be installed below the lowest horizontal branch connection point of the domestic sewage.
3.1.17 The expansion and contraction of pipelines caused by changes in environmental temperature can be calculated using the following formula:
In the equation: Δ L – Pipeline expansion and contraction amount (m); L – pipeline length (m); A – Linear expansion coefficient, adopted; Δ T – Temperature difference (℃).