Pump Curve Understanding

Years ago, making a pump selection meant sitting down with large printed catalogs and flipping through them until you reached a pump curve that fit a project’s hydraulic requirements. Today this process is made much easier through the use of electronic pump curve catalogs. One of the most well-known developers of electronic pump catalogs is Engineered Software and their pump selection software pump-flo. Another popular option for pump selection software is Intelliquip. All of the curves in this article were generated by Pump-Flo’s web-based pump selection software. What is a Pump Curve? A pump curve is a graphical representation of the performance … Continue reading Pump Curve Understanding

Centrifugal Pump Designs

In a previous article, we discussed some common impeller and casing designs. This article will consider what happens when you put the two together. End-Suction Pumps End-Suction Pump from Wikimedia Commons The most common centrifugal pump design is the end-suction pump. This type of pump combines a volute casing with a variety of impeller designs. Most typically, a radial flow impeller would be used, but in certain specialty applications, Francis-vane or mixed-flow impellers may be used. End-suction pumps are used in a large range of applications. Standard end-suction pumps are commonly used in fire suppression, plumbing, HVAC, and municipal water … Continue reading Centrifugal Pump Designs

Centrifugal Pump Casings

The centrifugal pump casing is the component of the pump that converts all of the velocity created by the rotating impeller into a controlled and stable flow and directs it out of the pump through the discharge point. The most common type of casing is called a volute and it looks similar to a snail shell. Image from A Brief Introduction to Centrifugal Pumps by Joe Evans, Ph.D The impeller is placed within the volute. However, as you may have noticed in the image above, the impeller is not typically centered in the volute. Instead, the impeller is positioned so … Continue reading Centrifugal Pump Casings

Centrifugal Pump Impellers

The impeller of a centrifugal pump is rotated rapidly to impart velocity to a pumped liquid. If you’ve never seen a pump impeller before, visualize a boat propeller. When a boat propeller is rotated it imparts velocity to the liquid around it. As the liquid moves, that velocity forces the propeller to move forward in the water. Now imagine what would happen if the boat were anchored in place, firmly enough to prevent the boat from moving. Next imagine that the velocity generated by the boat propeller were contained and controlled so that a stream of water was created that … Continue reading Centrifugal Pump Impellers

Pump Components: Volutes, Casings, and Impellers

When you boil them down to the most fundamental components, pumps are made up of two components: An impeller which creates velocity through rotation, And a casing which converts velocity into pressure. There are different types of impellers and different types of casings. The way that different types of impellers and casings are combined produces all of the different types of pumps. Types of Pump Casings There two basic types of pump casings: volutes and diffusers. Whether we’re talking about volutes or diffusers, what all casings have in common is that they are designed to take energy in the form of … Continue reading Pump Components: Volutes, Casings, and Impellers

Centrifugal Pump

A centrifugal pump is a machine that uses rotation to impart velocity to a liquid and then converts that velocity into flow. Let’s break that definition down into its components so that we can consider each one in turn: A centrifugal pump is a machine. A centrifugal pump uses rotation to impart velocity to a liquid. A centrifugal pump converts velocity into flow. “A centrifugal pump is a machine.” Every centrifugal pump includes an assembly of mechanical components that make operation of the pump possible. This mechanical assembly includes the pump shaft mounted on bearings, the sealing mechanism that keeps the pump from … Continue reading Centrifugal Pump