On-Site Balancing Guide (balancing preparation, procedure, advices)

Introduction

This tutorial provides a comprehensive guide on on-site balancing of rotating machines. On-site dynamic balancing is crucial for maintaining machine performance as it addresses issues caused by imbalance, which can significantly affect operational reliability and longevity. This guide will walk you through the preparation, procedure, and essential advice for successfully balancing a rotor in its operational position.

Step 1: Preparing for On-Site Balancing

Before beginning the balancing process, it is essential to assess the machine's condition to confirm that the issue is indeed imbalance.

• Analyze Machine Condition: Check for any signs of wear or malfunction.
• Stable Operating Conditions: Ensure that the machine is running at a consistent speed and load throughout the balancing job.
• Resonance Frequency: Confirm that the balancing is conducted below the machine's first resonance frequency.

Step 2: Understanding On-Site Dynamic Balancing

The process starts with understanding the basic principle of dynamic balancing.

• Measure Unbalance: Begin by measuring the rotor's vibration while it is operational.
• Stop the Machine: After measurement, stop the machine to continue with the trial mass placement.
• Trial Mass Placement: Attach a known weight (trial mass) to the rotor to assess its effect on vibration.

Step 3: Initial Setup and Sensor Placement

Proper setup is crucial for accurate measurements.

• Attach Reflection Tape: Stick reflection tape on the shaft.
• Position Speed Probe: Point the speed probe beam at the tape while the machine is off.
• Start the Machine: Once the probe is correctly positioned, start the machine and initiate the measurement.

Step 4: Conducting the Trial Run

This step involves using the trial mass to gather data.

• Enter Trial Mass Weight: Input the trial mass weight into the system. Remember, this can be negative if you are removing mass.
• Mount the Trial Mass: Ensure the trial mass is securely attached.
• Start Measurement: Start the machine again and press the start button to take the measurement.

Step 5: Analyzing Balancing Data

After the trial run, evaluate the results to determine if further balancing is necessary.

• Check Balancing Quality: If you have entered the necessary rotor settings (Correction Radius and Rotor Mass), the system will display the unbalance and balancing quality values according to ISO 1940.
• Decide Next Steps: If the values are satisfactory, you may choose not to proceed further.

Step 6: Correction Weight and Position

If adjustments are needed, determine the correction mass and its placement.

• View Correction Data: The system will display the required weight and its phase (position).
• Mount Final Mass: Install the final balancing mass and remove the trial mass.
• Angle Adjustment: Use the trial mass position to set the angle for the final mass. A negative value indicates a position against the direction of rotation.

Step 7: Conducting the Correction Run

This step verifies if the corrections have resolved the imbalance.

• Start the Machine Again: After mounting the final mass, start the machine.
• Take Measurement: Press the start button to take another measurement.
• Repeat If Necessary: If the results are not satisfactory, repeat this process, adjusting the mass as recommended after each measurement.

Conclusion

On-site dynamic balancing is essential for maintaining the efficiency and reliability of rotating machines. By following these steps—preparing the machine, understanding the principles, conducting trial runs, and making necessary corrections—you can effectively manage imbalance issues. Regular monitoring and adjustments can help prolong the life of your machinery and enhance operational performance. Consider documenting your balancing process and results for future reference and continuous improvement.