alignment and balancing

By Victor Wowk, P.E.

Historically, 1.0-mil peak-to-peak displacement has been quoted by many field balancers as the desired goal. This is a good number to strive for, but may be overbalancing in some cases. The 1.0 mil came from balancing rebuilt motors on a soft-bearing balancing machine with velocity transducers integrated to displacement. The 1.0 was an easy number to remember and the vibration was barely perceptible. The shop balancer then applied this same 1.0 mil when taking his instruments out to a field balance job.

With Jason Steed What is Angular Soft Foot?

Angular Soft Foot is a condition that occurs when a gap under a motor's foot is "non-parallel" to the mounting base. Because of this gap, the foot, when tightened, is forced to seat itself to whatever angle allows it to make total surface contact. As a result of this seating, stresses are created in the motor's foot that transfer through the motor "leg" and into the housing.

Alan Luedeking of Ludeca Inc.

Good sheave alignment will increase efficiency by reducing premature wear or failure of belts, pulleys and bearings. This can be accomplished by several different alignment methods, such as the labor-intensive string and straightedge method (most common), or by laser. The latter, in the form of the DotLine Laser^TM Pulley Alignment Tool, is new to the sheave alignment field, but has proven itself in greatly reducing downtime and the manpower needed to do the alignment, while simultaneously achieving far greater accuracy. This results in great labor savings and increased production uptime.

by Damian Josefsberg

Machine train alignment doesn't have to be a complicated, mind boggling task. There is a basic step by step procedure to follow which will allow you to maximize all of the benefits of aligning a machine train. When you follow this procedure and adhere to its principles, you will find that machine train alignment can often be easier to accomplish than a one coupling "vanilla" alignment.

By Damian Josefsberg

There is more than meets the eye when performing a turbine diaphragm alignment. It is not as simple as lining up all of the diaphragm bottom halves against a common reference line. To perform a correct diaphragm alignment it takes a lot of information, calculations, and time. If you plan properly, use the correct techniques, and technology; you will save time on the diaphragm alignment process and have a virtually rub free start-up. This can shave days to weeks off of your shut down and cause your turbine to operate more efficiently, thus saving lost production and increasing turbine output.