How do you perform failure analysis on pneumatic actuators?

Actuator failure analysis methodology: document failure mode and conditions (position, timing, operating conditions), external inspection (diaphragm tears, corrosion, seal leaks), internal inspection (springs, guides, bearings), component measurement (spring rate, diaphragm condition), review operating history (cycles, pressure extremes, temperature), and compare to design specifications. Common failures: diaphragm rupture (age, chemical attack, over-pressure), spring failure (fatigue, corrosion), stem seal leakage (wear, improper packing), and positioner malfunction. Root cause analysis: determine whether failure is design, manufacturing, installation, or operation related. Document findings, implement corrective actions, and update maintenance procedures.