Removal of heavy oil deposits and grinding sludge from hydraulic cylinder flanges

A large hydraulic cylinder flange from an open-pit mining excavator presented one of the toughest cleaning challenges Keertek’s lab has faced: thick, compacted grease mixed with mineral dust and metal wear particles.

The flange’s threaded bores and seal grooves were packed with a hardened grease-sand composite that resisted conventional solvent soaking. Keertek tested a dual-frequency ultrasonic system with a high-alkalinity industrial degreaser heated to 80°C. The low-frequency band (28 kHz) generated aggressive cavitation for bulk contaminant removal, while the high-frequency band (68 kHz) reached into threads and blind holes for precision cleaning.

After 25 minutes, all grease and particulate were eliminated. Threads were clean and undamaged, and seal surfaces showed no corrosion. The mining company — operating a fleet of 40+ excavators — requested a scaled proposal for an on-site cleaning bay.

Process: Dual-frequency ultrasonic, 80°C | Substrate: Alloy Steel | Contaminant: Heavy grease, mineral dust, metal particles