Introduction to cause-effect chain analysis plus with an application in solving manufacturing problems

Abstract

Root-cause analysis (RCA) is useful in solving inventive problems in any area including manufacturing. It often plays the central role because the root causes revealed can directly imply directions for solutions. This study introduces a new RCA method called cause-effect chain analysis plus (CECA+), improved from the existing method, cause-effect chain analysis (CECA). CECA+ uses a single diagram built and updated in seven steps to manage all the main information of a problem solving process in a systematic and intuitive way. The seven steps are problem definition (1), building and verifying cause-effect chains (2, 3), building and verifying solving direction chains (4, 5), and building and verifying idea chains (6, 7). Based on the theory of solving inventive problems (TRIZ), it can help users to reveal hidden, overlapping or contradictory causes and to generate comprehensive solving directions semi-automatically. It also greatly improved the drawing convenience and readability by using a versatile free diagramming software and a set of intuitive and systematic drawing conventions. CECA+ has been used successfully in many problem solving projects. Application to solving a real problem in manufacturing process was described with tips for using.