7 Wastes in PMs: Defects (Part 8 of 8)
Work that contains errors, rework, mistakes or lacks something necessary
The last of the 7 Wastes is the one that is most frequently targeted, often to the exclusion of the other six. (Over-Production, Transportation, Motion, Waiting, Processing and Inventory. See our previous posts for more information about the first six wastes.)
Defects are often a significant percentage of total manufacturing costs and reducing this waste is a major focus of many cost reduction or improvement initiatives. When defects occur, they can create issues in addition to the material cost through requiring re-inspections, rescheduling and capacity loss. Waste through defects can be from scrap through process failure, reworks from misloaded parts, field failures in equipment, missing parts, variation or batch process defects.
Defects Waste in PMs:
* Inferior or inappropriate PM task. Training or systems limitations
* PM Tasks performed incorrectly or taking longer due to vague information. Assumption that people should know what to do, poor planning function.
* Equipment failures where no PM strategy exists. Poor PM Development process, OEM manuals, new equipment.
Blog Series Conclusion
In summary, the categories used to define the 7 Wastes in Production are directly applicable to optimizing Preventive Maintenance strategies. The use of these categories will help identify the wastes in your maintenance processes and permit either immediate removal of the waste or implementation of culture changes that will give you long-term improvement in your PM program.
When done in isolation, PM Optimization (waste removal) yields tremendous impacts on craft labor, as well as increased reliability by doing the “right” PM. But when done as part of a Lean maintenance management system, can double the amount of work that an existing team can accomplish.