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　 　Hygienic manhole How is the strength?

　　Sanitary Manhole Strength and Testing: To ensure peace of mind with sanitary manhole products, it is essential to purchase from reputable manufacturers. For added safety, always follow the instructions provided in the user manual during operation. Today’s products are suitable for a wide range of industries and offer numerous advantages. The following provides relevant information about these products:

　　Since we designed a hygienic‑grade manhole, we selected a plate thickness of 0.8 mm to 1.0 mm. At this thickness, the structure can meet strength requirements even when storing large volumes of liquid, which has raised some doubts. However, relevant technical and design data demonstrate that, despite the thin material thickness, the stainless steel exhibits high strength, excellent toughness, and good elongation. As long as key process parameters are carefully controlled during manufacturing, the design and fabrication of large‑capacity stainless‑steel water storage vessels are entirely sound and can be successfully implemented.

　　High‑grade sanitary manholes, serving as construction components for hundreds of households, must ensure that water contamination does not compromise public health. During long‑term operation, they should remain resistant to oxidation, free from biochemical degradation, and prevent the formation and precipitation of corrosive substances such as heavy metals—particularly chromium and nickel ions. To meet these requirements, we design and manufacture stainless steel products; SUS304, in particular, is an acid‑resistant stainless steel that exhibits excellent corrosion resistance, superior metal‑rolling properties, and strong resistance to highly oxidizing acids. Consequently, when used as tank material, it can fully withstand exposure to low‑concentration hydrochloric acid (HCl), hypochlorous acid (HClO), weakly oxidizing carbonic acid (H2CO3), and other similar acids, thereby satisfying the prerequisites for sanitary‑grade manhole applications. Stainless steel manholes are installed on the top of tanks as safety‑critical emergency ventilation devices, typically paired with fire‑prevention and mechanical breather valves. This configuration not only prevents sudden overpressure or vacuum conditions—which could otherwise lead to tank damage and accidents—but also serves as a flame‑arresting barrier, making it an essential safety safeguard for the tank. When installing stainless steel manhole covers, the flange mating surfaces must be perfectly flat, with no wobbling or twisting. During tightening of the fastening bolts, apply torque diagonally to avoid deformation of the manhole cover.

　　 Hygienic manhole The key difference between a manhole and a handhole lies in their intended applications: a sanitary‑grade manhole is an inspection opening located along the routing of communication‑system cable‑laying conduits, allowing access for equipment inspection or maintenance during routine operations and accommodating personnel. In contrast, a handhole, being smaller, is designed only to permit a hand to pass through. On the surface, the sealing of a sanitary‑grade manhole consists of a robust, circular manhole cover, whereas a handhole typically features a relatively weaker, load‑bearing rectangular cover plate. In terms of dimensions, although sanitary‑grade manholes come in a wide variety, they generally adhere to standardized sizes and are considerably larger; handholes, by contrast, are fewer in number, much more compact, and their size and depth are tailored to specific site conditions and requirements. Functionally, sanitary‑grade manholes serve as transfer and relay points within the backbone communication network, while handholes act as terminal nodes in the distribution network. Geographically, sanitary‑grade manholes can be installed along urban arterial roads, sidewalks, and other major thoroughfares, whereas handholes are restricted to sidewalks and landscaped green spaces.