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This post was last edited by ly-7 on 2018-8-22 at 10:13. Answer: (l) Width of the pipe gallery: l) The width of the pipe gallery is primarily determined by the number of pipes and their diameter. Taking into account a certain reserved width, generally a 10%–20% margin should be left for the main corridor pipe racks, while also considering their load. At the same time, the effects of structures such as equipment and passages beneath the pipe gallery, as well as air-cooling equipment above it, must be taken into account. If it is required to install instrument cable trays and power cable trays, their required width should also be taken into consideration. The pipes in the pipe rack can be arranged in a single layer or a double layer; a triple layer can also be used if necessary. The width of the pipe gallery should generally not exceed 10m ； 2) When air coolers are installed on the pipe gallery, the span between the supports should be the same as the distance between the air coolers, so that the centerlines of the pipe gallery columns and the air cooler supports align ； 3) When installing pumps under the pipe gallery, consideration should be given to the layout of the pumps as well as the width of the passages required for operation and maintenance. If the cable used to power the pump is laid underground, the required width of the cable trench must also be considered. In addition, the required width of the main pipes for the cooling water and drainage pipes of the pump must also be considered ； 4) Since the pipeline layout density varies throughout the entire pipe tunnel, there are usually fewer pipelines in the sections at the beginning and end of the tunnel. Therefore, if necessary, the width of the pipe galleries at the beginning and end can be reduced, or a double-layer pipe gallery can be converted into a single-layer one. (2) Span of the pipe gallery: The column spacing and the span of the pipe gallery are determined by the allowable bending deflection resulting from the vertical loads exerted by the pipes laid therein, and are typically 6–9 meters. In small and medium-sized installations where there are many small-diameter pipes, a secondary beam can be installed between the two supports to reduce the span of the pipes. Additionally, the spacing between the pipe rack columns should be consistent with that of the equipment frame pillars to allow pipes to pass through. In the case of concrete pipe racks, a φ20 round steel bar or steel plate should be embedded at the top of the crossbeam to reduce friction between the pipes and the crossbeam. (3) The height of the pipe gallery can be determined based on the following conditions: l) Space across the road. When the utility tunnel crosses above a road, its clear height shall be as follows: ① The maintenance access within the tunnel should be no less than 4.5 m; ② Factory roads should have a clear height of no less than 5.0 m ； ③The railway should be no less than 5.5m ； ④The maintenance passage under the pipe gallery should be no less than 3m. When the pipe rack has trusses, it shall be calculated based on the height at the bottom of the trusses. 2) Minimum height of pipes under the pipe gallery. To make effective use of the duct space, pumps are often installed beneath the pipes. Considering the operation and maintenance of the pump, at least 3.5m is required ； When pipes on the pipe rack are connected to sectional equipment, they should generally be 600–1000 mm lower or higher in elevation than the pipes on the lowest layer of the pipe rack. Therefore, the minimum elevation of the pipe bottom at the bottom layer of the pipe trench is 3.5 m. When shell-and-tube heat exchange equipment is installed under the pipe gallery, the increased height of the equipment requires an increase in the clear height available there. 3) Height difference between vertically intersecting pipe galleries. If the ducts change direction or intersect at right angles, the height difference depends on the minimum size required for connecting the pipes, with 500–750 mm being a suitable range. A height difference of 1000 mm can also be used for large installations. Structural dimensions of the pipe gallery. When determining the height of the utility tunnel, the structural cross-sections and types of the transverse and longitudinal beams must be taken into account; it is essential that the heights of the beam bottoms and the framework bottoms meet the requirements specified for determining the tunnel height. For double-layer pipe galleries, the spacing between the upper and lower layers is generally 1.2 to 2.0 meters, which is primarily determined by the diameter of the largest pipe in the gallery. As for the height of the pipe gallery between the units, it depends on the specific conditions of the area through which the pipe racks pass. If the tank area is located along the edge of the factory, in areas that do not affect traffic within the factory or future expansion, pipe supports can be used for installation, considering economic factors and ease of maintenance; a height of 300–500 mm above the ground level is sufficient to meet the requirements. Insulated pipe support, adjustable shrinkage hole