Turbine Blade Coating To Combat Wear

ABB Turbocharging is offering special axial turbine blades with hard-faced tips to counter accelerated circumferential wear for engines burning lower qualities of heavy fuel oil (HFO) and particularly with heavy duty operating profiles.

ABB Turbocharging’s turbine blades with hard wear resistant tips are designed to scrape away hard HFO fouling on turbocharger turbine diffusers to minimize contact of the standard blades with the abrasive deposits.

ABB Turbocharging is offering special axial turbine blades with hard-faced tips to counter accelerated circumferential wear for engines burning lower qualities of heavy fuel oil (HFO) and particularly with heavy duty operating profiles.

A build-up of hard, abrasive combustion residues on and around the turbine diffuser causes wear due to contact between the deposits and the rotating turbine blades. This causes a gradual reduction in turbine diameter and consequent increase in exhaust gases bypassing the turbine. The resulting loss of turbocharger efficiency reduces engine efficiency and increases operating cost remedied only  replacement of the complete set of turbine blades.

ABB’s special hard wearing turbine blades, nicknamed “dragon’s teeth” have a hard, wear resistant layer applied to the tips of the removable turbine blades. Only three pairs (6 in total) of the hard tipped blades need to be fitted at 120 degree intervals around the turbine wheel to effectively scrape away hard HFO deposits and clear a path for the standard blades, thus minimizing contact with the abrasive residues. The 120 degree spacing of the coated blades also assists rotor balancing as well as ensuring a well distributed scraping effect.

Tests in the field have proven that by fitting dragon’s teeth, wear on the standard tubine blades is within tolerance and do not require to be changed at overhaul: maintenance of the diffuser is similarly reduced with only the six dragon’s teeth requiring replacement.

Dragon’s teeth turbine blades will be an option on new turbochargers and will be offered as part of ABB’s “Hot Part Package” which also includes modified washing nozzles for ABB Turbocharging’s TPL -A and TPL -C turbochargers on engines operating on HFO.