What is Carbon Ring Mechanical Seal:

Carbon ring seals are commonly used in various fan factories, offering easy installation.

The carbon ring seal structure includes a circular sealing cavity and a circular sleeve. The sealing cavity features a circular groove, which is at least fitted with two circular graphite sealing rings with a rectangular cross-section. There is a gap of 0.01~0.04mm between the inner diameter of the graphite sealing rings and the circular sleeve. The outer surface of the sleeve is coated with a wear-resistant layer, typically made of aluminum oxide or silicon dioxide.

Carbon ring seals may require additional isolation gas, usually nitrogen, with consumption rates controlled between 25 to 4 nm³/h, primarily used for sealing flammable and toxic media.

Carbon ring seals are a reliable and stable sealing solution designed for compressors and fans, offering easy installation and removal.

The sealed cavity features an upper and lower split structure, with the sealing ring in a three-lobed design. The shaft sleeve is typically integral (but can also be designed in a split configuration) and coated with HRC >70 ceramic. The segmented ring sleeve fits over the shaft sleeve's coated area, is tightened externally with a spring, and secured in the cavity slot with a stopper plate. During operation, the shaft sleeve rotates with the shaft, while the sealing ring and body remain stationary.

This sealing has two sealing points: the dynamic sealing point is located at the inner diameter of the sealing ring and the outer diameter of the sleeve. The static sealing point is at the end face of the sealing ring and the sides of the sealing body groove. Strict control of the roughness and dimensional tolerances of the sleeve outer diameter and the sealing ring inner diameter can control the leakage of the medium at the dynamic sealing point. Strict control of the flatness, parallelism, and dimensional tolerances of the two ends of the sealing ring and the sides of the sealing body groove can control the leakage of the medium at the static sealing point.

Carbon ring sealing achieves the purpose of sealing through the above principles. Carbon ring sealing is generally used for sealing gaseous mediums. For flammable, explosive, toxic, and other harmful gases, it is possible to introduce an isolating gas or liquid. The pressure of the isolating gas or liquid should be 0.1 to 0.2 MPa higher than the medium pressure to achieve zero leakage of the medium.

Carbon ring seals can be divided into three categories: general carbon ring seals, pneumatic carbon ring seals, and water-filled carbon ring seals. Among them, pneumatic carbon ring seals are widely used, with the isolation gas typically being nitrogen, with a consumption rate of approximately 6 m³/h (when the shaft sleeve outer diameter is Φ100). Carbon ring seals can withstand pressures below 2 MPa and are suitable for operating conditions with temperatures below 200°C and rotational speeds up to 150 m/s.

Therefore, the carbon ring seal has gained widespread application due to its simplicity in operation and maintenance, as well as its excellent sealing properties.