How often should non-welded piping be inspected?

 Non-welded hydraulic piping—flared, flanged, and compression and push-to-connect joints should be checked visually every three months (or every 400-600 hours of operation) in normal use and every week under extreme-duty conditions and provided with a complete torque check and leak-path inspection every scheduled maintenance interval or following any pressure increase or other system disturbance. Since non-welded joints are reliant on mechanical clamping force rather than the fusion process, they are more susceptible to thermal cycling than welded joints, and that is the reason the frequency of inspections should be linked to criticality and duty cycle instead of a specific date in the calendar. 

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