【Common Issues in Haichuan Pipeline Design】When arranging pipelines, it is important to adhere to the basic principle that pressurized pipelines should give way to non-pressurized pipelines

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During the design, installation, and inspection of pipelines, various minor issues that have been overlooked or not taken into consideration are often identified. These issues are collected and organized into a series; this list is being updated continuously. Everyone is welcome to actively participate in discussions. It’s a compilation post on common problems in HaiChuan pipeline design – it’s still being updated, and discussions are welcome: https://bbs.hcbbs.com/thread-5705828-1-1.html ------------------------------------------------------------------ The basic principle of “pressurized pipes giving way to non-pressurized pipes”. The basic principle of “pressurized pipes giving way to non-pressurized pipes”. The table below can help you quickly understand the core reasons behind this principle and its relationship with other avoidance rules. Principle Classification: Brief explanation of specific principles. Core principle: Pressurized pipes should not interfere with non-pressurized pipes. Non-pressurized pipes (such as drainage pipes) rely on gravity to flow; they require a strict slope and are not suitable for bends ； Pressurized pipes (such as water supply pipes) transport fluid under pressure, allowing for relatively flexible route adjustment. Other important avoidance principles: Although larger pipes are more expensive, have larger dimensions, and are harder to move, their location should be determined first. Cold water pipes require insulation, while hot water pipes need to be insulated as well; this is costly, and frequent bends can lead to gas accumulation. Pipes with fewer attachments allow those with more attachments, such as valves and flanges, to have sufficient space for operation and maintenance. Temporary pipes give priority to permanent pipes in determining the location of facilities for long-term use. Understanding the logic behind the principles, and knowing the reasons behind them, can help you make more rational decisions in practical situations. The “rigidity” requirement for pressure-free pipes: The fluid inside pressure-free pipes (such as sewage pipes and stormwater pipes) flows from higher to lower levels due to gravity. This means it must maintain a certain slope and be laid as straight as possible. Any unnecessary turns or changes in elevation can lead to poor drainage, reduced flow rates, and even the deposition of impurities and blockages in the pipes. Therefore, its installation route is relatively fixed, with little room for adjustment. The “flexibility” characteristic of pressurized pipes: Pressurized pipes (such as water supply pipes and fire hoses) rely on the pressure provided by devices like pumps to transport fluids. Changing its direction or adding bends may increase some resistance, but it generally does not have a decisive impact on the core functions of the system. Therefore, in the event of a cross-conflict, adjusting the route of the pressured pipeline is a more feasible and less impactful solution. Comprehensive considerations in practical applications: In actual pipeline integration design (especially in ceilings with limited space), in addition to the basic principles mentioned above, various other factors are taken into account. The vertical arrangement order of pipes: When multiple pipes are arranged in layers within a vertical space, they are usually arranged from top to bottom, with heat-carrying pipes placed above and cold-carrying pipes below ； Gas pipes are on top, liquid pipes are at the bottom ； Insulated pipes are on top, while uninsulated pipes are at the bottom ； The high-pressure pipes are on top, and the low-pressure pipes are below. This is mainly for reasons of safety, energy consumption, and ease of maintenance. Utilizing building structure space: To maximize space savings, the height within the beams is usually fully utilized. While meeting the requirements regarding the turning radius, air conditioning ducts or pressurized water pipes can be laid beneath the beams to avoid conflicts with other pipes and ensure sufficient interior headroom