Benchmark PdM

Horizontal Shaft Alignment

The most common shaft alignment is horizontal alignment.

Easy-Laser® offers two programs for this, one is the standard Horizontal Program that takes shaft measurements at the 9, 12, 3 o’clock positions. The other is EasyTurn™: a program that allows you to take readings with as little as 40 degrees rotation of the shafts, starting anywhere in the rotation. This is a great advantage when rotation is restricted because of piping etc. 

Some laser systems like you to take measurements as you rotate the shaft. This is because they are more susceptible to back lash in the coupling. Other laser systems focus on speed. This is not an advantage for you-- the end user-- because if you think about it, it’s not a race. The goal is accuracy not speed. And ask your self if you have a better chance at hitting a moving target or a stationary one? 

Many of you have used dial indicators to do alignment work. So you will know that the greater the distance between the dial indicators the more accurate the reading when you are doing the Reverse Dial method. With Rim and Face method the greater the distance between measurement the greater the accuracy. And so it is with laser systems: the greater the distance between the detectors more stable and accurate the reading. 

 

 

All Easy-Laser® systems use dual beam technology. With dual beam lasers, the accuracy depends on distance A. Which is the distance between the detectors. The greater the distance, the greater the accuracy. With the single beam system, the possible accuracy depends on distance B between the detectors. 

 

 

 

This distance is usually very short because both detectors are mounted in the same housing (normally about 50 mm). In reality, with the measurement units installed on each side of a coupling, distance A is, in most cases, always longer than distance B. [1: housing, 2: laser LED, 3: detector, 4: laser beam].