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Recently I was listening to the musical comic Allan Sherman sing “Good Advice”. It is a silly song about how he (Allan Sherman) travels through history, and gives advice to some of the greats of the past – which results in the greats of history achieving their destiny. Here is one verse about the great Austrian psychiatrist Sigmund Freud (considered by many to be the father of psychoanalysis) …

“Sigmund Freud, he had an unfurnished house.
He was a very nosy fellow, so it seems.
He had no chairs,
So he made all his friends stand around all day
And tell him about their secrets and their dreams.
Well, while they stood there talking ‘till they got fallen arches,
They yelled, ‘My feet are killing me. Ouch!’
I said, ‘Sigmund, don’t you realize you’ve got a gold mine here.
Go out and buy yourself a leather couch.’”

And then he goes into the chorus

“And that was good advice, good advice.
Good advice cost nothing, and it’s worth the price.”

Now, I am telling you this because it relates to some advice I gave to a client. And I gave the client advice for free. I will let you decide if I did the right thing, but I am trying to build a relationship with this client.

The client contacted me, describing how they needed to increase the flowrate through their pumping systems. The pumping system (all constant speed motor driven centrifugal pumps) had a booster pump and a main pump in series (pump pair), and they had four pump pairs (duty, duty, duty, standby … 4×33% pairs). The booster pump was significantly smaller than the main pump. The pump pairs were required because of the combination of high pressure rise, high flowrates, and volatile fluids, and flowrate flexibility. He said he needed to increase the flowrate and was going to achieve this increase by upsizing the impellers.

Well … upsizing the impellers is a viable option for increasing the capacity of the pump, but it has the potential to overload the system (motor too small, motor cables too small, extra flowrate / pressure can overload downstream safety systems, etc). I told him this, and he replied that he was only looking for a 5% increase in flow. While my list was valid, the magnitude of my concern could be reduced – as many of these issues were changed from a detailed engineering study to a simple check (with potential follow-up work on items that were identified as marginal).

He was going to upsize 8 impellers – one for every single pump.

At this point, I decided to give him what I considered good advice. For free. My effort was about 45 minutes. I will let you decide if I succeeded in giving him good advice.

I asked for the pump curves. He sent me two pump curves (one typical curve for the booster pumps, and one typical curve for the main pumps). The curve was for a constant impeller size with various speeds. Using the affinity laws and a simple spreadsheet, I made four pump curves.

+ the current composite curve for the existing booster and main pump

+ a composite curve for a booster pump with a new impeller and an unchanged main pump

+ a composite curve for an unchanged booster pump and a main pump with a new impeller

+ a composite curve for a booster pump with a new impeller and a main pump with a new impeller (his base case).

The third option (unchanged booster pump and a main pump with a new impeller) provided about 95% of the benefit, and for about 65% of the cost (eliminating the need to modify four small pumps).

As I write this, I do not know if he has used my “good advice”, but he did acknowledge receipt, and clearly understood the implications.

Companies must make strategic decisions, which are often not based on simple economic decisions. This was one – I decided I wanted to invest in this company as a client, and hopefully build a better and longer lasting relationship with them.

Anyway … was my advice good advice, and did I do the right thing to give it for free?