Abstract: Condition-based maintenance(CBM) policies and predictive maintenance(PdM) policies are emerging maintenance policies. However, comparative studies on CBM/PdM policies and traditional CM/PM policies are critical for industrial applications of CBM/PdM policies, but are very limited. Based on the failure times and condition monitoring data of BGA packages of lead-free solder joints, the application flowchart of a PdM policy is demonstrated. In addition, a quantitative comparison among a CM policy, a PM policy, a CBM policy and the PdM policy is conducted. Moreover, the reason for the improvement of maintenance effectiveness of the CBM and PdM policies are investigated. The results show that the CBM policy and the PdM policy share more accurate and reliable predictions of product lifetimes when deciding the maintenance schedules, by fully utilizing their condition monitoring data. Consequently, the CBM policy and the PdM policy can better balance the risks (e.g., the maintenance cost, the cost of product failures) and improve the maintenance effectiveness.

Key words: preventive maintenance;condition-based maintenance;predictive maintenance;reliability, Grooved heat pipe, Isothermal characteristic, Heat-transfer capability, Continuous extrusion