When is dynamic alignment considered necessary?

Dynamic alignment is essential when a machine is in operation to measure its alignment under actual working conditions. This is critical because many factors can affect the alignment of rotating equipment when it is running, such as heat generation, vibration, and operational load. Static alignment might show that the machine is in line when at rest, but these parameters can change significantly once the machine is operational.

Dynamic alignment accounts for the real-world behavior of machinery, ensuring that it runs smoothly without excessive wear, vibrations, or misalignment during operation. This process often involves using specialized instruments and techniques to capture the performance of the machine while it is running, providing a more accurate and comprehensive assessment of its alignment in practical scenarios. By confirming alignment under dynamic conditions, operators can ensure enhanced efficiency, reduced risk of failure, and prolonged equipment life.

The other scenarios mentioned do not account for the critical factors influencing alignment during operation, making them less suitable for determining the machine's effectiveness in a real-world setting.