HI Pump FAQS January 2012
Answers to the industry's pressing technical and management questionsQ.  When purchasing new rotodynamic pumps, what type of acceptance testing is recommended?A.  Purchasers of rotodynamic...
Hydraulic Institute Pumps FAQs June 2010
Balancing Pump Impellers; High Efficiency Pumps; Boiler Feed Booster PumpsA. Pump impellers are typically balanced in accordance with ISO 1940 balance quality grade G6.3 or better (see Figure B.2)....
How Does Pump Suction Limit the Flow?
One of the advantages of centrifugal pumps over positive displacement pumps is an ability to operate with a wide flow range. Since a centrifugal pump operates at the intersection of a pump curve and a...
Analyzing the Impeller Eye
This is a follow-up to my column on predicting centrifugal pump performance (Pump & Systems, May 2011), and offers equations that will enable the engineer to perform a partial analysis of the...
Suction-Side System Design; If You Do Not Have Enough NPSHA; Resistance of Materials to Cavitation Damage
Final Article in a 14-Part SeriesSuction-Side System DesignCentrifugal PumpsFigure 1 shows most of the features discussed below.  Straight Run Into Suction For satisfactory operation, a...
The concept of “suction energy” was developed to enhance the evaluation of the NPSH characteristics of centrifugal pumps, but I fear that it misses the mark. Suction energy is defined as the...
Hydraulic Institute Pump FAQs September 2007
Q. What are the most probable causes of insufficient discharge flow or pressure in centrifugal pumps?A. Before looking at the pump, check the measurement of total head and rate of flow. The proper...
Hydraulic Institute Pump FAQs 2008
Q. I have heard that the rate of flow through centrifugal pumps can be regulated by submergence control instead of by throttling the pump discharge. How does this work, and does it damage the pump?A....
Hydraulic Institute Pump FAQs July 2011
Q. I see that many pumps for pumping slurries are made of either hard metals or elastomers. Why is this and which is better?A. A large variety of metals and elastomers are used for slurry pumps...
Hydraulic Institute Pump FAQs September 2008
Q. When operating centrifugal pumps on corrosive or erosive applications, how can the user determine when the casing wall is worn too thin for safe operation? What is the minimum safe operating wall...
 Solution to Pump Challenge #2: Moving a Pump from the Bottom of a Dry Pit
In the August 2009 issue, we considered the following challenge: From the available data tables, the vapor pressure of 150 deg F water is about 4 psia, or (x 2.31) = 9 psia.Initially, when the...
Oil Sands Pump Performance Testing and Limitations
Many millions are spent in the oil sands industry providing new plants for the production of oil from tar sands. Oil sands pumps are a key component in these expansions.The cost of non-conformance can...
Due to high specific gravity, viscosity and particle size of mining materials, centrifugal pumps are continuously challenged in mining applications. New pump technology was created to efficiently move...
There are two largely accepted facts about mining: 1) A mine's landscape is dynamic, and 2) Within that landscape, water is a mine's worst enemy. Navigating a mine's landscape with pumps designed to...
Q. Is it true that centrifugal pumps should be built with ball bearings that have greater than normal internal clearance?A. It depends on the pump type and the conditions of service for the...
1)  Only select pumps with suction specific speeds less than 11,000-less than 9,000 is even better.2)  Select your pump so it never operates below 70 percent to 80 percent of its best...
  Pumps & Systems, January 2008 Critical IssuesSERO PumpSystems GmbH is a well recognized manufacturer of side channel pumps that has been in operation for more than 100 years, but SERO...
Q. What is the maximum pumped liquid temperature that an end suction centrifugal pump can handle, and what must be done to a pump for it to operate successfully at that temperature?A. Limits are...