A standard centrifugal pump impeller is constructed of a group of elongated, solid-walled chambers attached together in the shape of a circular ring. The ring is spun quickly and the liquid that enters the inside end of the chambers is flung out at high speed from the other end. Figure No. 1 shows a section through centrifugal pump wet-end showing regions of low and high pressures.

I often hear the words “relays” and “contactors” used seemingly interchangeably, but there must be a technical difference, right? So, I took a quick trip to Rexel Automation Solutions in Salisbury, MD to meet with Nate Titus, Account Manager, and get the skinny on these beloved but sometimes pesky industrial workhorses.

Electric motor problems. This article presents a basic explanation of electric motor construction and operation along with twelve problems that can be encountered with their use. Most electric motors in industrial equipment are three phase alternating current induction motors. Induction is the creation of an electric current across a gap. Two types of induction motors are commonly used: squirrel-cage and wound- rotor. The names come from the way they are built.

The previous article in this series, “Understanding Shaft Alignment: Thermal Growth,” explained thermal growth and its affect on proper equipment alignment. A practical example involves a recent project at a wastewater treatment plant in Cleveland that needed realistic cold alignment targets for a 3600 rpm compressor to reach their accurate alignment targets.

This article covers the two main plant numbering systems that together form the framework on which all maintenance programmes are based and describes the value that can be created by integrating these identification systems. These two systems are: Equipment Numbers, or more accurately, Equipment Location Numbers Stock-Keeping Unit (SKU) numbers or, preferably, Material Catalogue Numbers. A third, less critical but still important numbering system for Stores location (or “bin”) numbers, is also included.

It is estimated that almost half (45 percent) of global electricity is used by electric motors. Electric motors drive a considerable amount of equipment in almost all industries, from power generation to water and food supply to consumer products. The importance of electric motors in modern society cannot be understated. It is because of this vital role that it pays huge dividends to keep your electric motors running efficiently through a quality reliability program that includes energized and de-energized electric motor testing (EMT).

Air receivers store compressed air and are used to temporarily satisfy fluctuations in plant air demand. There are other benefits of a wet receiver such as cooling and cleaning the air before it enters the air treatment equipment. Storage benefits highlighted below apply to all compressor control types. Understanding best practices for compressor storage for a lubricated trim compressor with load/unload controls is critical for optimized performance.