Misalignment is the root cause of 50 percent of failures in rotating equipment. While it’s the most common cause of failure, it’s also one of the most preventable, and new alignment technology is making alignment more accessible and accurate than ever.
Alignment is not a new concept, but over the past several decades, technological advancements have provided new ways to measure and correct misalignment. Single-laser alignment tools were the first to replace traditional methods like straight edges and dial gauges. While these single-laser systems marked a significant improvement, their limitations eventually led to the development of more advanced dual-laser alignment systems.
Single-laser dual-detector alignment systems are the most accurate, fastest, and simplest method of achieving precision alignment. As companies are facing increased pressure to lower utility costs, prolong machine life, and reduce downtime, adopting the single-laser alignment method presents a powerful option for accomplishing these goals.
Limitations of the Dual-Laser Alignment Method
Using dual laser alignment tools presents several challenges for technicians. The tools use two heads, each with a laser and a sensor, that attach to either side of the machine coupling, being aligned. Before starting the alignment, each laser needs to be adjusted with the sensor on the other head.
This requires twice as much initial setup adjustment on both sides of the machine versus only one adjustment of the single laser system. But the time cost doesn’t stop there.
Because of a phenomenon known as “divergence”, contact between the lasers and the sensors often goes out of range during measurement, particularly while measuring angular misalignments. As the shaft rotates, the laser position on the sensor detector increases, causing the laser to move out of the detector area.
Technicians must take several steps to avoid divergence. First, they often need to perform a pre-alignment, bringing the machines initially into closer alignment so the lasers can stay in contact with the opposing sensor during the alignment measurement process.
Advantages
The single-laser, dual-detector alignment method removes these obstacles to alignment and presents many benefits over the dual-laser method.
From the beginning, the single-laser system allows faster setup since there is only one laser and one sensor. Adjustments can be performed by technicians standing on only one side of the machine, and since divergence isn’t a factor, alignment can be achieved no matter the distance between the sensor and the laser.
Technicians can start using the single-laser system as soon as both heads are in place, since there is no need for pre-alignment. Not only does this save time during setup, but it also simplifies the alignment process for the technician.
The user interface shows technicians exactly which direction the machine needs to be moved and how much it needs to be adjusted after taking just one set of measurements.
Using the single-laser system allows the user interface to accurately record both the as-found and as-left positions of the machine, which is impossible when using systems that require pre-alignment. Companies can use accurate recorded measurement results to develop standards and protocols for their alignment processes, as well as build proof of the ROI for their alignment program.
Since all measurements are taken within the system itself, there’s no possibility for human error, such as initial rough and pre-alignment, as well as dial gauges that require manual visual measurements and recording.
'Good Enough' is No Longer Good Enough
Single-laser shaft alignment tools take alignments far beyond “good enough” and allow teams to achieve alignment within 0.01 mm accuracy. This level of precision brings machines into near-perfect alignment, allowing efficient energy transfer between machines. Precision alignment prolongs the asset lifespan, increases the time between failures, and reduces downtime and maintenance.
One of the biggest misconceptions around alignment is that flexible couplings absorb misalignment, and so precision alignment is not necessary. This is simply not the case.
Flexible couplings are not designed to compensate for severe misalignments. The coupling may not fail, but it transfers the excessive load and forces caused by the misalignment onto the bearings and the seals in the equipment.
Precision alignment protects not only the coupling, but also the lubrication bearings, the seals, and the gearbox on the rotating machinery that is either driving the machine or being driven through the gearbox. While flexible couplings can be roughly aligned in just a few minutes to achieve 'good enough' alignment, the resulting misalignment often leads to increased wear, requiring technicians to overhaul or replace pump seals and motor bearings more frequently.
Teams that think they are saving time by depending on flexible couplings to self-correct instead of performing precision alignment will find they are spending more time repairing machines and replacing “faulty” components.
The root cause of these problems is not the quality of the bearings or seals; the root cause is misalignment. Only by precisely aligning your rotating machinery will you reach and exceed the full manufacturer’s expected lifetime of components like bearings and seals.
Intuitive Tools Get Teams Aligning Faster
The best single-laser alignment tools are built with automated, intuitive workflows that provide step-by-step guidance and are simple to use, even for teams without previous alignment experience. Since these tools do not require technicians to pre-align equipment, technicians do not need to learn how to perform that task, reducing training time even further.
The more difficult task is performing the re-alignment itself, but even that can be made easier with features built into alignment tools. Features like a Live-Move application show the user exactly where to adjust the machine. And, by leaving the device mounted during readjustment, the user interface displays the alignment changes so technicians can follow the alignment process and see a real-time illustration of how their adjustments are impacting and improving the alignment.
Aligning with single-laser alignment tools is faster and more precise than other alignment methods. But the real question teams need to ask is not how quickly the alignment can be done; it is how long the machine will run without precision alignment. A well-aligned machine will always outlast one that is misaligned.
As equipment uptime, energy efficiency, and asset longevity become increasingly critical, the importance of shaft alignment cannot be overstated. Single-laser, dual-detector systems eliminate the barriers that once made precision alignment complex and time-consuming.
With faster setups, intuitive operation, and unmatched accuracy, they make it easier for teams to perform precise alignments by reducing downtime, cutting maintenance costs, and supporting a proactive reliability strategy.
