With the wide use of variable frequency drives in the pump industry and increasing unit size, it is becoming more difficult to design mechanical systems free from natural frequencies within operating speed range. If such an occurrence is allowed in the field, a resulting resonance condition threatens to significantly impact performance and longevity of the equipment.
In the oil and gas industry, custody transfer transactions involve transporting physical substance from one operator to another, including transferring raw and refined petroleum between tanks and tankers, tankers and ships and other transactions. An accurate account of the amount of material transferred is of great value to both the company delivering the material and the eventual recipient. This is especially true in bunker fuel oil delivery since a ship's bunker contributes to the ship's operating cost.
Few would dispute that variable frequency drives (VFDs) save energy, but the exact amount depends on the system. Hydraulically speaking, the main difference between a variable frequency (speed) drive and a discharge valve is that a VFD only changes a pump curve, while a valve only changes a system curve. A pump operates at the intersection between its H-Q curve and a system curve, and a change in either moves the operating point to a new intersection.
Frequency Hopping Spread Spectrum (FHSS) radio was invented during World War II by the military for communicating information and strategic plans to allied forces in a way that would counter enemy efforts to "jam" or intercept traditional radio communication frequencies.
For controller-to-controller coordination, wireless Bluetooth is an excellent alternative to Class 3 radios.
Enveloping is a tool that can give more information about the life and health of important plant assets. It is primarily used for early detection of faults in rolling element bearings and gearboxes. Enveloped acceleration is an especially valuable parameter to trend, as the progression of machine condition can be evaluated. Armed with good information and assisted by service experts, plant engineers can be confident in the proper operation and management of the important assets in their care.
In the last decade, ultrasonic flowmeters have grown in popularity in laboratory and process areas as a cost-effective, noninvasive alternative for measuring the velocity and flow rates of liquids and gases.
Have you ever wondered why a motor manufacturer would state that many of their 60-Hz motors will operate on 50-Hz power as long as you reduce the nameplate voltage by 1/6?
Introduced in June 2010, the VibXpert II (VXP II) has many different uses and functions. The primary use is to extend the lifespan of equipment within a plant or facility using vibration signatures. One of its many applications is detecting bearing faults, either early or pre-existing within the machinery. It can also detect cavitation within pumps.
Cavitation is a destructive condition that can destroy the inside of a pump before you even realize it is occurring. Early detection can minimize damage, reduce downtime, and save money. Cavitation involves the creation of bubbles formed when the fluid being pumped vaporizes due to a decrease in pressure as the fluid enters the pump. These bubbles are then acted on by the pump impeller, causing them to implode.
A recent marketing survey found that 84.0 percent of satisfied customers would "jump ship" for a better deal if an opportunity arose. With markets becoming increasingly globalized, customer retention has become a critical part of business strategy. Companies need to ask themselves: What reason can I give this customer to stay, even if my competitor offers a cheaper price? The keys lie in keeping customers loyal to brands and products and ensuring a consistently outstanding customer experience.
Outdated water systems are pumping beyond their original specifications, resulting in inefficient operation, higher maintenance and operation costs and the potential for a system shutdown. This article takes a look at updating the controls and pumps for a water system.
In recent years, adjustable frequency AC drives have become increasingly popular as they provide an efficient, direct method of controlling the speed of the most rugged and reliable of prime movers, the squirrel cage motor. They provide a spectrum of benefits for a broad range of applications.
Picture a manufacturing enterprise with plants in multiple locations around the world. Using a single automation platform that handles discrete, process and motion control with common programming, human machine interface (HMI) and standards-based networks, a night shift operator gathers and logs data on product quality from his production line.
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, vibrations gradually increase with time. This increase reflects the normal internal wear, accumulative misalignment and deformations that can occur within a pump. All these wear conditions will lead to eventual failure.
The service department of a variable frequency drives manufacturer frequently sees the following scenario: A frustrated user calls with what he perceives to be a defective piece of equipment. As the technician begins probing for information, the user's frustration boils over, often with an exclamation along the lines of "what a piece of junk!" As the service technician asks the pertinent questions, the exasperated user relays the details of a drive that is continually tripping on a fault until the user is at the end of his rope, not knowing what to do.
Today's electricians are often found working in applications outside the realm of what is traditionally considered "electrical." Through new programs sponsored by the IBEW-JATC training schools and others, the skill sets of the electrical union workforce have broadened to include automation and controls.
Traditionally, the primary use of drives has been in applications such as powering pumps, fans and conveyors. While they will continue to be used in these applications, today's end-users have a different approach from that of a decade ago.
Production, distribution and refining applications in the oil and gas industry rely heavily on motor-driven pumps and pumping systems. Keeping electric motors driving critical operations at peak performance is vital to ensure maximum profitability.