Pumps & Systems, June 2008 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,...
Due to the expense and labor required, most facilities need to maximize the life of their motors. Electrical, insulation resistance and thermal measurement are three tests that can troubleshoot...
Pumps & Systems, June 2008 Due to the expense and labor required, most facilities need to maximize the life of their motors. Electrical, insulation resistance and thermal measurement are three...
Pumps & Systems, June 2008Following the development of variable frequency converter drives during the 1990s, totally enclosed fan-cooled (TEFC) AC induction motors became viable options for...
An argument in favor of IEEE-841's provision for motor bearing protection.In June, 2007, a reader asked Electrical Apparatus magazine, "How long should motor bearings last?" The answer will astound...
Pumps & Systems, June 2008 An argument in favor of IEEE-841's provision for motor bearing protection. In June, 2007, a reader asked Electrical Apparatus magazine, "How long should motor bearings...
Pumps & Systems, June 2008Click here for "Focus on Fundamentals" Part 1, Part 2,  Part 4 and Part 5. In the April and May 2008 issues, we looked at centrifugal pumps....
Controlling the load is essential to ensuring the gasketed joint will seal properly. Previous Sealing Sense articles have examined the types of gaskets to use, how flange finish affects gasket sealing...
With sensor-equipped electrical submersible pumps (ESP), downtime can be minimized, unplanned costs can be eliminated and production optimized. In California, an operator experienced a power outage....
Pumps & Systems, June 2008Vibration is one of the most damaging forces in the industrial environment. Vibration not only reduces the life of equipment, but can also adversely affect the quality of...
Vast tonnages of oil sands are now being transported as slurries in centrifugal slurry pumps as the first stage of the bitumen extraction process. Similarly sized pumps are also used to transport the...
Pumps & Systems, June 2008While driving a car with the gas pedal to the floor and then controlling your speed using the brake is obviously inefficient, many facilities use the approach for pump...
Pumps & System, June 2008Bigger Is Better-Or At Least It Used To BeOwing partly to tradition, the shafts of electric motors are often larger than those of the equipment they drive. Engineers were...
Bigger Is Better-Or At Least It Used To BeOwing partly to tradition, the shafts of electric motors are often larger than those of the equipment they drive. Engineers were very conservative a century...
Pumps & Systems, June 2008With large-scale consolidations of OEMs in the pump industry and the closure of foundries in North America, advanced non-OEM pump rebuild shops have emerged that offer...
Pumps & Systems, June 2008The rotary lobe pump belongs to the positive displacement pump family. It is a dual shaft pump design with external timing gears, allowing two intermeshing rotors to...
Pumps & Systems, June 2008This two-part column addresses two major causes of premature pump and motor failure. Although it specifically addresses submersible wastewater pumps, it applies to any...
It is impossible to balance line-to-line voltages perfectly in a three-phase circuit. In fact, line voltages typically differ by a few volts or more, but a difference that exceeds 1 percent can lead...
Pumps & Systems, June 2008It is impossible to balance line-to-line voltages perfectly in a three-phase circuit. In fact, line voltages typically differ by a few volts or more, but a difference...
Pumps & Systems, June 2008Editor's note: This first in a series is based on the opening chapter of Optimizing Pumping Systems, A Guide to Improved Energy Efficiency, Reliability, and...
Pumps & Systems, June 2008 A look at how 3-level inverters can help reduce electrical damage to bearings. PWM inverters introduce motor shaft voltages and bearing currents. The bearing damage in...
Hydraulic Institute Pump FAQs June 2008
Q.When measuring vibration on vertical pumps, does the allowable vibration depend on the height of the motor or on the height above the baseplate where the readings are taken?A.The allowable vibration...