The tried and trusted elastomer-free, gas-lubricated EagleBurgmann PDGS mechanical seal was developed specifically for extreme requirements with high and low temperatures as well as high-pressure applications. Thanks to innovative design features, it handles even the highest pressures and requirements. High quality components such as polymer secondary sealing elements (U cups) make this a reliable universal seal in the oil and gas industry (LNG/PFSO ships), in pipelines, in refineries, or in the petrochemical industry.
In late 2015, this seal type underwent three months of testing and continuous operation at the EagleBurgmann test facility, as contracted by a leading LNG compressor manufacturer. It was the first time that this compressor seal with a shaft diameter of 11.8 in (300 mm) was tested for 2,000 hours in Turning operation. A rotational speed of seven RPMs with full sealing surface contact with dry nitrogen, and temporarily propane, put the seal through a grueling test. EagleBurgmann’s DiamondFace technology with the hardest known material offers maximum resistance against abrasive particles in the process gas. At the end of the test, the sealing surfaces showed no signs of impairment or destruction even though the sealing surfaces were constantly in running contact during Turning. Based on this outstanding result, the manufacturer granted its approval to install EagleBurgmann PDGS mechanical seals in its compressors. Typically, seal faces are engineered for only a very limited period in Turning operation, as longer Turning periods usually lead to increased wear and destruction of the sliding surfaces.
Added safety below the lift-off threshold - also for ratcheting - is provided by seal faces with this DiamondFace coating. The shaft here is rotated further by 45 degrees at specific intervals to avoid thermally-induced deformations to the shaft. The sliding surfaces have full contact in this operating state as well.
The successful 2,000-hour test result clearly shows the high performance of this sealing type and the seal faces with DiamondFace technology. Several years ago, EagleBurgmann's innovation helped set a milestone in mechanical seal technology because these mechanical seals are characterized by their extreme hardness and wear-resistance, excellent thermal conductivity and chemical resistance.
The pressure operating range of the seal generally covers 0 – 6,525 PSI (0 - 450 bar). Stable leakage rates and a safe operating behavior distinguish the PDGS in all operating states. When used in low temperatures, the dynamic secondary seals exhibit outstanding mobility. They satisfy all requirements such as automatic alignment, resistance to extrusion, and temperature and chemical resistance. These are properties that give the compressor seal, and thus the entire system, a high degree of operational safety and availability.
Technical features of the PDGS
- Excellent chemical resistance of the face materials in aggressive acids, alkaline solutions and bases
- High rigidity of gas film
- Optimized aerodynamic 3D gas grooves with self-cleaning effect
- Available in different materials for optimal chemical resistance, also with the EagleBurgmann DiamondFace technology
- Ready-to-fit unit
Shaft diameter dn 1.14” - 13.98” (29 - 350 mm)
Operating pressure p 6,525 PSI (0 bar - 450 bar)
Operating temperature t -274°F - +446°F (-170°C - 230°C)
Sliding velocity vg 2 - 656 ft/s (0.6 - 200 m/s)
Turning .5 ft/sec (0.15 m/sec)
For more information on the PDGS, contact us at firstname.lastname@example.org.