No. Not just anyone can balance an impeller. Yes, done properly a balancing machine is used. An experienced machinist could do it without a balance machine, but you and I could not.
I had worked at a company that was the master distributor of Alfa Laval. (Sanitary supplier) We would buy all of the centrifugal pumps with full impellers. and then cut the impellers down to match the requirements based off of the pump curve.
We never balanced them.
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