Equipment Knowledge
Troubleshoot AC Motors – Part 2
Troubleshooting AC Motors, part 2, will help you determine the issue when a motor runs noisy.
Equipment Knowledge
Equipment Knowledge
Troubleshoot AC Motors – Part 1
Troubleshooting AC Motors, part 2, will help you determine the issue when a motor won’t start or a motor accelerates too slowly.
Equipment Knowledge
Pumps: You Get What You Pay For… Or Do You?
One of the most costly mistakes that almost every company makes with its pumps is to actually buy the wrong pump. Sadly, this is a situation that occurs with much more frequency than anyone would care to admit. The ramifications are truly enormous—and they are magnified even more in tough economic environments. Efficiency drops. Reliability plummets. Maintenance costs rise dramatically. Even in the best of times, you couldn’t afford to gamble on the efficiency and reliability of your pumping systems. Don’t start now.
Equipment Knowledge
Who Should Recondition My Seals?
Such a question often comes up when it is time to recondition a mechanical seal: We use several different brands of mechanical seals in my plant. When a pump is taken out of service, we usually send the seal back to the original seal manufacturer for reconditioning. One of my suppliers has offered to recondition all of my seals, regardless of brand. Is this a good idea? Most process plant maintenance departments return their used mechanical seals to the original seal manufacturer (or Seal OEM) for reconditioning.
Equipment Knowledge
What is a valve?
The valve is one of the most basic and indispensable components of our modern technological society. It is essential to virtually all manufacturing processes and every energy production and supply system. Yet it is one of the oldest products known to man, with a history of thousands of years.
Engineering
Understanding Shaft Alignment: Basics
Part one of a four-part series that will cover alignment fundamentals and thermal growth, and highlight the importance of field measurements through two case studies. Despite the best efforts to precisely align rotating machinery shafts, dynamic movement (commonly believed to be due to the thermal growth of the machine casings) has resulted in machines operating at less than optimum alignment conditions. This vexing problem has plagued machine reliability professionals for decades.
Engineering
Understanding the ‘Diesel Effect’ and How it Damages Hydraulic Cylinders
I was recently engaged by a client to conduct failure analysis on a large (and expensive) double-acting cylinder off a hydraulic excavator. This cylinder had been changed-out due to leaking rod seals after achieving only half of its expected service life. Inspection revealed that apart from the rod seals, which had failed as a result of the ‘diesel effect’, the other parts of the cylinder were in serviceable condition. The diesel effect occurs in a hydraulic cylinder when air is drawn past the rod seals, mixes with the hydraulic fluid and explodes when pressurized.
Equipment Knowledge
The 7 Secrets of Pump Reliability
Contrary to popular opinion, a centrifugal pump is not designed to develop a specific head at a certain capacity as requested by the pump purchaser. In fact a pump is designed and built to produce a whole range of head-capacity conditions as identified by it’s performance curve. The pump will operate on that curve if it is driven at the designated speed.
Equipment Knowledge
The Pump Affinity Laws 2-1
There are occasions when you might want to permanently change the amount of fluid you are pumping, or change the discharge head of a centrifugal pump. There are four ways you could do this, of the four methods the middle two are the only sensible ones. In the following paragraphs we will learn what happens when we change either the pump speed or impeller diameter and as you would guess other characteristics of the pump are going to change along with speed or diameter.
