Sulzer Boiler Feed Water
Application: Boiler Feed Water
Pump Details: Sulzer 4x6x10.5 MSD 4-Stage
Pump Type: Multi-Stage Horizontal Split Case
Upon inspection of the paper mill's failed boiler feed pump, Hydro determined that the pump seized due to loss of the thrust bearing. Though the failure caused extensive damage to the pump, Hydro rebuilt the pump with upgrades to improve rotor stability, protect the pump against dry run conditions, and improve the overall efficiency.Hydro reverse engineered the shaft, which had been damaged by excessive heat and wear on the thrust bearing end, and manufactured a new one from a more durable stainless steel. Hydro also manufactured new impeller wear rings and case rings from upgraded material. All stationary wear components, except the throat bushing, were manufactured with composite materials to improve rotor stability. Rotor stability is greatly improved due to the reduced running clearances that are possible with composite materials - typically clearances can be reduced by 50%.
The first stage impeller was weld-repaired, stress-relieved, and machined back to standards. The clearance between the case and stationary components was returned to OEM standards. The impellers were individually balanced, then the assembled rotor was balanced to 2 W/N.