CobaDGS: the first zero-emissions mechanical seal for compressors

CobaDGS from EagleBurgmann is the first gas-lubricated mechanical seal to completely eliminate climate-critical leakage. It is a nitrogen-supplied dry gas seal that can be used at high pressure, making it also suitable for compressors used by gas network operators. An optional supply unit can be implemented to generate nitrogen on site and thereby reduce transportation costs.

Previously, gas-lubricated mechanical seals could not achieve the zero methane gas emissions target except when operating at low pressure. The newly developed CobaDGS completely prevents leakage even in turbo compressors - both during operation and at standstill.  Using this solution at natural gas compressor stations eliminates nearly all methane emissions. In most cases, the compact design will require no adaptation of the compressor housing. It is also suitable as an upgrade for single, tandem or double seals.

Greater security, less maintenance

The engineers at EagleBurgmann have added secondary seal faces to back up the CobaDGS mechanical seal behind the previous coaxial CobaSeal and have designed the components for significantly higher operating pressures. In addition, the CobaDGS is permanently supplied with clean, dry nitrogen rather than process gas. This renders the usual venting of the compressor during a shutdown unnecessary, while significantly reducing the effort required for seal maintenance. The system can handle operating pressures of up to 160 bar delivering the same level of security as a tandem seal. In the event of nitrogen failure, it can continue functioning safely and robustly with process gas, eliminating the need to stop the compressor in such situations.

High-pressure nitrogen generator for on-site production

In addition to the seal, EagleBurgmann can supply an optimally designed system for the on-site generation and supply of nitrogen if needed. The nitrogen is extracted from the air via pressure swing adsorption at an operating pressure of 6 bar. For storage, it is compressed to 330 bar and dynamically adjusted to the required pressure level. The nitrogen itself is supplied at 0.5 bar above the sealing pressure. The new seal has been in operation as a pilot project since mid-October in France, implemented as a complete solution in a compressor station.


Sales via EagleBurgmann Germany in Wolfratshausen and all international branches: Tel. +49 8171 23 0, info@eagleburgmann.com, www.eagleburgmann.com