In the late 90s, I used Excel to develop a simple graphical system that showed the variable speed performance of a pump based upon its published 60-hz H/Q curve. I have modified it to model several...
Vibration Analysis Simplified
Last year in “Trending Revelations in Vibration Analysis,” (Pumps & Systems, June 2009), I discussed the importance of statistic trending in vibrations analysis. Usually, as most would expect,...
Vibration Analysis to Improve Pump Reliability and Save Energy
 Vibration analysis trending can be a helpful tool in predicting brewing problems, before they develop into a big issue. The Kemira/FinnChem plant (Kemira) in Augusta, Ga., started a vibration...
When we start the pump selection process for a particular application, one of our major concerns is efficiency. If several different models of similar quality meet our conditions, we will usually...
Proper installation and adjustment can make the difference between the success and failure of a packed pump. By keeping in mind the fine points of a few key principles, the chances of success are...
Consider a typical sewage collection system. At the initial point of discharge, water first flows (by gravity) into a network of (sloped down) drain pipes, which gradually intercept a larger main...
What is a Safe NPSH Margin for a Centrifugal Pump? Can You Provide Too Much NPSH?
Editor's Note: This is the fifth article in the year-long series, Understanding NPSH. To read the previous article, click here. To read the next article, click here.What is a Safe NPSH Margin for a...
What is a Safe NPSH Margin for a Centrifugal Pump? Can You Provide Too Much NPSH?
What is a Safe NPSH Margin for a Centrifugal Pump?The Hydraulic Institute NPSHA Margin Work Group (1) recommended NPSH margins ranging from zero to four times the NPSHR (NPSHA÷NPSHR = 1 to 5). The...
Born in the 3rd century BC, pumps are one of the most important mechanical devices in all industrial applications. Sustaining their importance in a mature market characterized by steady growth and...
Almost all centrifugal and rotary pumps require a sealing system to provide sealing integrity of the drive shafts carrying the impellers and protect against pumped fluid leakage and the environment...
Some may question if this is an appropriate topic for a pump magazine. While I do admit that I am a staunch conservative, this column is not about the political left. Instead, it addresses a very...
Best Efficiency Point and Best Operation Point
Best Efficiency Point (BEP) is the point at which a pump is least prone to failure and its life expectancy is greatest
Hydraulic Institute Pump FAQs June 2008
Q.When measuring vibration on vertical pumps, does the allowable vibration depend on the height of the motor or on the height above the baseplate where the readings are taken?A.The allowable vibration...
Q. What are the criteria for determining the maximum allowable forces and moments that can act on a centrifugal pump's nozzles without damaging the pump? What part of a pump is most likely to be...
Pumps & Systems, August 2007Q. Is there a way of predicting the maximum operating speed for a reciprocating plunger pump when pumping a viscous liquid?A. Yes, but let's begin by setting the basic...
Hydraulic Institute Pump FAQs October 2006
Q. Due to a recent thrust bearing failure in one of our deep well pumps, we would like to determine the down thrust on the bearing from the pump. Is there a simple way of calculating this?A....
A New Way to Skin a Cat-Part 1
A Simplified Method for Monitoring Pump PerformancePump users should regularly monitor the condition of their critical centrifugal pumps to keep them operating efficiently. Otherwise, lost production,...
Centrifugal Force & Affinity- It's All About Velocity
Why do those three affinity laws do such a good job of predicting the performance of a centrifugal pump when its rotational speed or impeller diameter is changed? Well, it turns out that they are not...