A new dimension of gas-lubricated separation seals

EagleBurgmann has completed tests of the to date largest coaxial, gas-lubricated separation seal "CobaSeal" with positive results. This seal is now also available for shaft diameters of 355 mm and its range of application extends to compressors in any plant in the oil and gas industry such as refineries, LNG and petrochemical plants, for example.

The CobaSeal seals the bearing chamber of the shaft in centrifugal compressors and prevents oil from penetrating the gas-lubricated main seal. It consists of a rotating seat made of ductile material and a stationary, spring-loaded seal face.

95 % less leakage

Extremely low leakage is an essential feature of the CobaSeal. Compared to separation seals such as labyrinths or seals with carbon rings, the values of the CobaSeal are down by as much as 95 %. The need for nitrogen is reduced accordingly, so much smaller nitrogen generators than usual are sufficient to supply the seal. Compared to conventional sealing solutions on the market, the plant operator can save at least USD 50,000 per year and compressor due to the reduced nitrogen requirement when using one CobaSeal. In addition, the special material combination for the stationary seat and seal face also allows operation with ultra-dry nitrogen.

Considerable increase of operational safety of the compressor

The design of the seal face and stationary seat ensures that axial and radial movements of the shaft in the sealing gap are easily compensated. The rings are contact-free in any operating condition and thus wear-free as a result. Customer planned maintenance intervals for the plant can be extended accordingly. Even if the main seal fails, the process gas cannot penetrate into the bearing chamber. This considerably increases the operational safety of the compressor.

The CobaSeal works perfectly even under special operating conditions such as extremely low speeds (slow-roll or turning) and when the compressor coasts down. Special settings are not necessary - which is convenient for the system personnel.

Video: CobaSeal XXL

EagleBurgmann CobaSeal - the biggest co-axial separation seal ever built. Watch the video now!

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