Huntly Power Station has four single reheat 250 MW turbo-alternators which are now at the end of their design life. Each boiler’s feed water is supplied by a single 9 MW steam turbine driven four stage cartridge style centrifugal pump running between 3000 and 5400 RPM. Typically, the cartridges last 8 to 12 years (40,000 to 50,000 hours) before internal wear causes the efficiency to drop off and the cartridges are replaced with a refurbished one (a rotable spare). The cartridge on unit 2 has now done 20 years (78,000 hours) but because Unit 2 was due to be de-commissioned in 2018 the cartridge has not been changed. Recent changes to load demands and other plant restrictions means that we are forced to continue to run this worn-out pump. This paper details the high vibration causing rapid bearing and seal deterioration, changes to balance response making balancing impossible, and the fight to keep this pump in service.

Simon Hurricks was born in the UK and Immigrated to New Zealand in 1957. Simon gained a NZ Certificate in mechanical engineering in 1974 and has been employed by Genesis Energy Ltd and its predecessors for 47 years and has been stationed at Huntly power station for 38 years as Predictive Maintenance engineer. Simon has specialised in vibration analysis and balancing for 41 years and has extensive experience in solving resonance issues and modal balancing of flexible shafts. Simon was treasurer and past president of the Vibrations Association of NZ and has presented papers at all of their 29 annual conferences. Simon has had articles published by both Bently Nevada and BK Vibro.