What are the main technical requirements for sealing rings?
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1) The flatness of the sealed end face shall not exceed 0.0009 mm (i.e., three monochromatic light interference fringes)； The roughness Ra value of the sealed end face of hard materials shall not exceed 0.2 μm ； The end face roughness Ra value of soft materials shall not exceed 0.4 μm ； The surface shall be free of defects such as cracks, scratches, pores, and porosity that could affect its performance. 2) The parallelism between the sealing surface of the seal ring and the surface in contact with the auxiliary seal ring shall comply with the accuracy grade 7 specified in GB1184-80. 3) The perpendicularity between the end face of the sealing ring and the inner (or outer) circular surface where the auxiliary sealing ring is installed shall comply with the accuracy grade 7 requirements specified in GB1184-80. 4) The surface roughness Ra value at the contact area between the sealing ring and the auxiliary sealing ring shall not exceed 3.2 μm ； The dimensional tolerance for the outer diameter or inner hole is hg or Hg. The above requirements apply to the sealing rings of mechanical seals used in ordinary pumps; for mechanical seals used in reactors with lower rotation speeds, these requirements can be relaxed appropriately or relevant standards can be referred to, whereas higher requirements apply to high-speed mechanical seals.
The main technical requirements for the sealing ring are summarized as follows: 1. Flatness of the sealing surface: The flatness of the sealing surface is extremely important, as it directly affects the sealing performance. It requires a flatness of no more than 0.0009 mm, that is, not exceeding three monochromatic light interference fringes. This ensures the sealing quality and reliability of the sealed end face. 2. Roughness of the sealed end face material: The Ra value for the roughness of the sealed end face of hard materials should not exceed 0.2 μm, whereas for soft materials, this value should not exceed 0.4 μm. These requirements are intended to ensure good seal surface contact and reduce leakage. 3. Surface quality: The sealed end face should be free from defects such as cracks, scratches, pores, and porosity, as these defects can affect the performance of the sealing ring as well as its service life. 4. Parallelism and perpendicularity of the sealing ring: The parallelism between the sealing surface of the sealing ring and the surface in contact with the auxiliary sealing ring, as well as the perpendicularity between the end surface of the sealing ring and the inner (or outer) circular surface where the auxiliary sealing ring is installed, shall comply with the accuracy requirements of grade 7 as specified in GB1184-80. 5. Surface roughness at the contact area between the auxiliary sealing ring and the main sealing ring: The Ra value of the surface roughness at this contact area should not exceed 3.2μm, in order to ensure an effective seal. 6. Dimensional tolerance: The dimensional tolerance for the outer diameter or inner bore should be hg or Hg, to ensure an appropriate fit between the sealing ring and the corresponding components. Depending on the application scenario, the technical requirements for sealing rings also vary. For example, for mechanical seals used in reactors with lower rotation speeds, the aforementioned requirements can be relaxed appropriately, whereas for high-speed mechanical seals, these requirements may be more stringent. When designing and selecting sealing rings, the technical requirements should be determined by referring to relevant standards and the specific needs of the application scenario. .