High-Velocity Oil Flushing

When performed correctly with proper engineering and equipment, oil flushing will not damage turbine bearings or seals. The key is maintaining appropriate flow rates, velocities and temperatures that effectively clean while staying within safe operating parameters for your specific equipment.

B&W Energy Services performs incompressible fluid modeling during the planning phase to confirm that design flow rates and velocities will be achieved without exceeding equipment limitations. We calculate Reynolds numbers to ensure a turbulent flow necessary for effective cleaning while respecting manufacturer guidelines.

Our variable-frequency drive-equipped skids allow precise flow control rather than forcing oil through systems at excessive rates. Temperature cycling is carefully controlled to optimize viscosity for debris removal without damaging seals or gaskets.

The risks come from inexperienced providers who use improperly sized equipment, inadequate engineering or poorly maintained flushing systems. This is why choosing a contractor with proven oil flushing expertise and purpose-built equipment is essential to protecting your valuable turbine assets.

Oil flushing is a dynamic pre-commissioning or maintenance cleaning process that circulates oil at high velocities through entire lubrication systems to dislodge and remove contaminants, while oil filtration is the continuous process of removing particles from oil during normal equipment operation.

Oil flushing uses external high-volume pumps and filtration equipment to achieve velocities and flow rates far exceeding normal operating conditions, specifically designed to break loose trapped debris from bearing lines, dead legs and piping. The process continues with repeated cycles and thermal variations until OEM cleanliness specifications are met.

Oil filtration happens during regular operation through onboard filters that maintain oil cleanliness but cannot remove construction debris or achieve the aggressive cleaning needed before initial startup.

Think of oil flushing as the deep cleaning required before moving into a new house, while filtration is the ongoing housekeeping. B&W Energy Services’ high-velocity flushing process uses specialized external equipment that generates flow rates dramatically higher than those of operational filtration systems, completing in days what operational filters could never accomplish.

Oil flushing is complete when oil samples consistently meet or exceed OEM particle count specifications and cleanliness standards for your specific equipment.

B&W Energy Services performs systematic oil sampling throughout the flushing process, analyzing particle counts with automated counters that measure contamination levels in accordance with ISO cleanliness codes.

Samples are typically taken from multiple locations in the system to ensure uniform cleanliness. The flushing process continues with thermal cycling and high-velocity circulation until consecutive samples demonstrate stable, acceptable particle counts that satisfy manufacturer requirements. Different equipment types have different cleanliness standards—gas turbines typically require extremely low particle counts, while some hydraulic systems may have less stringent requirements.

We provide documented test results showing particle count progression and final cleanliness achievement. OEM specifications often require specific ISO cleanliness codes, such as 15/13/10 or better. Our engineering team knows the exact requirements for all major turbine manufacturers and ensures your system meets those standards before declaring the flush complete.

Thermal cycling in oil flushing is the process of systematically varying oil temperature during flushing operations to optimize contaminant removal. As oil temperature increases, viscosity decreases, allowing the oil to flow more easily into tight spaces and dead legs where debris hides. The thinner, heated oil suspends particles more effectively and carries them back through filtration systems at accelerated rates.

B&W Energy Services’ flushing skids include integrated heating components and heat exchangers specifically designed to cycle lube oil temperatures during flushing. The increased flow velocities through our high-volume pump systems naturally generate friction heat, which we harness and control to maintain optimal oil temperatures.

By alternating between different temperature ranges, we create expansion and contraction cycles that help break loose stubborn particles adhering to piping walls and bearing surfaces. This thermal cycling approach, combined with high-velocity circulation and vibration tools, is a key reason B&W can complete oil flushing in 5-7 days, rather than the 1-2 month timeline required by traditional methods.