Mechanical Seal for Heavy Duty and High Pressure applications

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Many industrial processes and, particularly Oil&Gas and Power, more often require pumps capable to work at very high pressures.
Mechanical seal must guarantee a high level of reliability and avoid dangerous emissions for people and environment.

API682 IV edition standard limits covers applications with pressure up to 40 bar; beyond this limit, each manufacturer refers to his own experience and the seals are identified as “engineered”. With API682 V edition, an extension will be included, creating a guideline for this type of application.

Good seal operation is a combination of good lubrication (stable liquid film between sliding faces) and low leakage level.

The difficulty to maintain a stable liquid film between the two sliding surfaces at high pressure is the engineer’s goal. Lubrication’s lack can be caused by many factors, including transient phases, such as start-up, which is one of the most critical phases for high pressure application, as the torque is 4 -5 times greater than the operational torque. This lack could impact correct operation of the seal due to friction increase and over-heating.

Seal designed by Fluiten for these challenging operating conditions is developed with a patented drive device, which can withstand high run-out levels or even misalignment under high stressing conditions. Furthermore, this solution allows to maintain the planarity of the seal faces by using monolithic rings, with regular geometry and thickness. Last, but not least, seal faces can be designed incorporating the “Fluilift” groove technology, which maintains process liquid stability also at high P x V factor (Pressure x Peripheral shaft speed).

Developed with finite element analysis, engineered FluitenHPK seal model is available in customized cartridge construction according to API arrangements 1, 2, or 3, which means single seals, dual unpressurized or double pressurized solutions.