Broken shaft in centrifugal pump
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Lime slurry pump: Check valves cannot be installed on the pipes, and the shaft keeps breaking at the turbine nut. Seeking a solution
The pipeline doesn’t have a check valve; do you mean the impeller will rotate in reverse when the machine stops?
Drill a hole slightly axially eccentric from the cap and thread it to prevent backspacing
Why can it break? Is it due to the long-term reversal caused by fluid backflow? Can’t it be controlled with the valves before and after the machine? Or it might be caused by an installation issue.》
Was it medium backflow that caused the pump shaft to break, or was there some other reason? What about the cross-sectional view of the broken shaft?
Medium backflow causes shaft breakage? I thought the solution was to increase the shaft diameter at the impeller nut
Broken shaft due to reverse rotation of the impeller? That’s unlikely. Are there any photos? That would make it clearer; it seems the shaft is too thin – it needs to be made thicker and longer
It’s likely a problem with the shaft design, as well as whether the operating vibrations are above the acceptable level. If the vibrations are indeed excessive, it’s very probable that the pump shaft was not designed properly – the nut holding the impeller is too thin, resulting in stress concentration
Ours doesn’t send power in one direction either, but it hasn’t reached the point where the shaft breaks; it just reverses direction, and there’s a concern that the impeller might fall off
Stress concentration occurs at the threads; fracture should occur when the load changes. Is the lime slurry mixed evenly? Did it break when starting or stopping the pump, or was the problem during normal operation?