Robust mechanical seal for subsea pumps
In cooperation with a well-known pump manufacturer, EagleBurgmann Germany GmbH & Co. KG, Wolfratshausen, Germany, has developed a mechanical seal for High Pressure / High Temperature (HP/HT) applications. The seal has been specifically optimized for subsea pumps designed for an absolute pressure of up to 1,000 bar and ambient temperatures of up to 180 °C. It seals the motor and bearing unit in the pump against the multiphase medium crude oil.
More than twenty years of experience with subsea applications have gone into this development. The result is a product that is robust against diverse, extremely fluctuating operating conditions. Different process media, changing speeds, pressure ratios or temperatures cannot affect the seal. It corresponds to the life cycle of subsea pumps in deep-sea oil and gas production plants.
The seal is pressurized externally to achieve noticeably improved rigidity of the medium in the sealing gap even under fluctuating operating conditions and which ensures sufficient cooling at high temperatures.
In addition, the seal is completely free of elastomers in order to deal with the high pressures. Instead, a U-cup is a simple and clever secondary seal to separate the barrier fluid from the process fluid even in the event of a pressure reversal.
EagleBurgmann equips the mechanical seal with DiamondFace® technology. This provides the sliding faces with a microcrystalline diamond coating that protects them from wear caused by solids-laden media and enables partial dry running.