Shaft misalignment can occur in rotating machines that are connected by a coupling. In fact, a majority of rotating machines used in the manufacturing industry are out of alignment. Operation within certain tolerances allows for proper transmission of power with minimal wear and tear. Over time however, any rotating machine can move out of these tolerances due to circumstances such as soft-foot, a bent shaft, loose bolts, poor base conditions, pipe strain and various other inconsistencies. Shafts that are out of alignment put strain on rotating machines, resulting in a loss of power transmission as well as damage to, and even failure of, the bearings, couplings, and other associated components.
To ensure that your rotating machinery stays within recommended tolerances, here are a few steps to detecting and correcting shaft misalignment:
Initial Diagnosis
How do you know if your rotating machinery is experiencing shaft misalignment? There are a few ways to detect issues before they cause costly damage to your machinery. A few indicators include:
Figure 1
• Shaft misalignment can be determined by unique vibration FFT patterns in VibePro software (Figure 1)
• Parallel misalignment will present as peaks as 1X, 2X and 3X in the radial direction in the vibration FFT (Figure 1)
• Angular misalignment will present as peaks at 1X, 2X and 3X in the axial direction in the vibration FFT (Figure 1)
• An operating temperature, especially at the coupling, that is higher than the normal ranges for your equipment
• Improper tightness/quality of foundation bolts as well as coupling bolts
• Premature failure of the bearings, seals, couplings, or shafts
• Excessive oil leakage around the bearing seals
• Excessive vibration compared to similar equipment
• Shaft damage near the bearings or couplings
• Excessive coupling wear
If your rotating equipment is experiencing any of these indicators, or other forms of failure, it may be necessary to move on to the next step of misalignment diagnosis: measurement.
Measurement of Misalignment
By measuring your shaft alignment from different points along the horizontal and vertical planes, you can determine exactly how far out of alignment your shafts are and whether you are dealing with angular misalignment or offset (parallel) misalignment or, typically, both.
VibePro simplifies the process of measuring shaft alignment with its laser shaft alignment solutions. Laser measuring units are attached to the shafts, and the shafts are rotated and measured in 3 positions. Measurements of the distance from the stationary machine through the machine train to the movable machine allow VibePro’s shaft alignment measurement tools to calculate both angular and parallel misalignment and provide a solution for correction – both in the vertical and horizontal (live) direction. Clear, on-screen directions walk the user through the alignment process.
Realignment and Repair
Once measurements have been taken, the next step is to correct the moving machine’s alignment according to its angular and offset inconsistencies. Depending on how long the shaft was experiencing error, it may be necessary to replace seals, bearings, bolts, or other components that could have been damaged by the misalignment. A complete inspection of the machine train is recommended before starting any alignment. A professional OEM-alternative spindle repair provider will have the experience and training to properly adjust and realign shaft positions for optimal performance.
Predictive Maintenance
Choosing and implementing a focused predictive maintenance program can ensure that your rotating machinery is operating the way it should, and help monitor factors at your plant that are causing your equipment to malfunction or fail. Flexible monitoring solutions provided by an experienced OEM alternative allow for the cost-effective maintenance of your manufacturing plant, resulting in decreased operating expenses and increased uptime. Find out more on predictive maintenance here.
About VibePro
At VibePro, it is our mission to provide the best predictive tools on a single platform and services to monitor nearly any asset. We strive to bring our customers the portability, connectivity, and affordability offered by the latest available technologies. Our product family combines vibration data collection and analysis with balancing, shaft alignment, thermography, and ultrasound into an affordable and completely scalable solution on one simple to use platform. VibePro’s predictive technology apps feature many additions that have come directly from customers. Click here to learn more.
