Advanced Repair Technology for RB211 HPT and IPT Blades

L3667 Oxidation Resistant Weld Alloy

The Liburdi repair for the HPT blade employs a high strength, oxidation resistant weld metal – L3667 alloy is proven in industry tests to have greater oxidation than the original blade metal.  Shroud weld repairs with L3667 alloy achieve a full 24,000 hour service interval with no metal loss: the parts are then repairable for additional service. 
  
Rejuvenation Heat Treatments

The Advanced Repair includes Liburdi's propietary FSR^® Full Solution Rejuvenation^®(leading the industry since 1980) which effectively restores the blade alloy strength.  The process restores the blade set to a “zero hour” condition to enable the parts to be treated as new for extended service.   FSR^® Rejuvenation processes are Authorized by Rolls-Royce and are applied to the Advanced Repairs for both the HPT and IPT blade sets, with some 40,000 blades rejuvenated and over 100,000 reliable hours on sets in service.
 
Service History – HPT, IPT Blades

The Advanced Repair is being used by some 16 customers in over 200 RB211 engines worldwide. One major operator, with a large fleet of RB211s, adopted the repair as a strategy to reduce maintenance costs and has over $30 million dollars while enjoying 100% reliability with the repair over the past 12 years.

   
Advanced RB211 Repairs – HPT, IPT  NGVs and Shroud Seal Segments

NGVs and Seal Segments that were previously rejected because of thin walls or metal loss can now be reliably recovered with the Advanced Repairs.  Advanced Repairs using high strength LPM® powder metallurgy technology are now being used for the RB211  Nozzle Guide Vanes and Seal Segments. 

The LPM® repair enables the wall thickness to be reconstructed with high strength superalloy material, and have been proven in service since 1996. Previously these parts were declared unrepairable by conventional weld repair methods. 

Advanced RB211 Repairs - HPC Compressor Vanes

Compressor vanes that were previously being replaced with expensive new parts are now able to be repaired by advanced weld repair methods at Liburdi.  As an example the Mod 475 Stage 5 Vanes repairs are able to avoid a $45,000 new parts cost to the operator at each overhaul.