Columns

Here I go again, writing about net positive suction head (NPSH).

Today, some of the world’s most profitable oil refineries use pure oil mist on thousands of rolling element bearings. Pure mist is often considered the “gold standard” and has been in successful use at refineries owned by ExxonMobil, Chevron, Shell and others for more than 40 years. Forty years of experience in solid, safe, reliable hot service with temperatures as high as 400 C validate their value.

"Wishin’ and Hopin’”—both Dionne Warwick and Dusty Springfield had hit versions of this pop song in the early ’60s. The lyrical message is that you will not get want you want if you just sit around wishing and hoping; instead you need to take action to achieve the desired outcome.

In this issue of Pumping Prescriptions, I will answer a common question I receive from readers related to system curves for boiler feed systems.

The old joke about falling from a tall building is that “it isn’t the fall that kills you, it is the sudden stop at the bottom.” When it comes to cavitation, it is not the formation of the vapor bubbles that kills the pump, it is the subsequent collapse.

Last month, I discussed why a pump should be aligned nine times and declared that four of those alignment adjustments should be made before the pump is started up.

I received good feedback from the readers on my January 2019 P&S article “Calculating vs. Estimating Pipe Velocity.” Below are some of the letters and my responses.