Why is it essential for machines to be tested under load?

Testing machines under load is crucial because materials tend to expand when heated, which can significantly impact clearances and alignment. When a machine operates, it generates heat due to friction and other operational factors. This thermal expansion can alter the physical dimensions of components, resulting in misalignment or changes in clearance that might not be present when the machine is at rest or not under load.

By conducting tests under load conditions, engineers can obtain realistic data that accurately reflects the machine's operational characteristics. This is vital for diagnosing potential issues, ensuring proper functioning, and prolonging the machine's life. Accurately assessing how the machine operates under realistic conditions helps to identify potential failures or inefficiencies that may not surface during unloaded testing.

In contrast, testing without load may not reveal these issues, making it less effective for predictive maintenance and reliability analysis.