Problems with removing the impeller
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There are currently two centrifugal pumps (one for water supply and one for backwashing with salt water), made of high-silicon cast iron. When the impellers are removed for maintenance, they are often damaged; sometimes even destructive removal methods are used, which is a great waste. How do other sailors go about removing the impellers? Do such methods also cause damage to these high-silicon cast iron impellers?
I have never disassembled a cast-iron impeller. For the situation you described, my suggestion is: 1) Heat it using steam or gas welding. 2) Can several screw holes be drilled in the impeller, and a screw hole be machined on the shaft end, using a special tool similar to one used for drawing?
Use low-pressure steam to blow across the impeller in a circular direction; it is necessary to pull it out before the shaft gets hot, as it will not be possible to pull it out once it heats up. Wait until it cools down and then try pulling it out again, repeating this process until it is removed.
Does your facility have a boiler steam discharge tank? Still inside for an entire morning; it can be taken apart in the afternoon!
Under normal circumstances, there is a gap between the impeller and the shaft; you can increase this gap by 0.005 mm, so that the impeller will not get damaged when removed
When we encounter this problem, we usually pull it out after heating the impeller
Hehe, let me share my own opinion – try reversing the motor. Well, it’s a matter of torque; generally, the impeller of a centrifugal pump is mounted on the shaft. If reversed, it will cause the assembly to loosen, after which it is heated with steam. Utilizing thermal stress
It is best to create a set of specialized tools designed specifically for disassembly, using heating as a method for that purpose
The centrifugal pump is made of high-silicon cast iron; when the impeller is removed for maintenance, it is often damaged, and even destructive removal methods are used. Since the model of the pump in question is unknown, its assembly method is also unclear. There is no way to discuss the disassembly method.
Change the clearance between the shaft and impeller to 0-0.03mm for easier disassembly.
The impeller in your case is connected by keys, right? This allows the gap between the inner hole of the impeller and the shaft to be increased, with the keys and impeller lock nuts ensuring the transmission of power.