Floating Carbon Rings vs Dry Gas Seals in CO2 Compressors: When to Use Which

In the centrifugal compressor, two sealing solutions are often compared: the floating carbon ring and the dry gas.

The Carbon Circle.

These are carbon segment ring wrapping around the axis, creating very small gaps to limit gas leakage. The structure is simple, heat-resistant and high speed, but still has a certain amount of gas leakage and needs to be treated with gas leakage.

The dry air.

Using a gas film between the two non-contact sides. According to Atlas Copco, in field tests, compared to standard carbon rings, the dynamic dry gas film emits only a small fraction of the CO2 amount, while the short length of the material helps shrink the size of the compressor.

Combine the two.

In fact, many compressors use a combination of floating carbon rings and dry gas cylinders. Carbon rings act as separation cylinders or secondary cylinders, and dry gas cylinders take the main function of sealing.

suggestion of choice.

• Very low leakage and emission control: Dry gas removal priority.
• High temperature conditions, dirty lips or simple requirements: consider carbon rings.
• Total cost of life cycle and support system.

Source of reference.

Atlas Copco (CO2 compressor materials), synthesis of industry practices. Article synthesized and reinterpreted by SNS-VN; brand name belongs to the owner.