Finding causes - solving problems sustainably.
Root Cause Analysis (RCA) comprises methods for identifying the actual causes of faults or problems in products and processes.
The aim is not to treat symptoms, but to identify the true source of the problem and eliminate it permanently.
Root cause analysis is a central component of many quality management systems, such as Six Sigma or the 8D process.
When root cause analysis becomes necessary
Root cause analysis is primarily used when problems can no longer be solved by experience alone – for example, when known products fail under new operating conditions or unexpected errors occur.
Procedure and methodology
The basic idea of all RCA methods is to describe the problem (symptom) as precisely as possible, followed by a narrowing down of the potential sources of the problem and the subsequent systematic tracing of the error path.
A distinction is made between theoretical analyses and test-based methods.
Problem level
- Cause level
- Cause level
- Cause level
Theoretical root cause analysis
Known procedures are the:
- 5-Why question technique
- 6M method (Ishikawa)
Both approaches are valuable tools, but they reach their limits when dealing with complex problems, as they are often unable to identify combined causes.
System analysis according to Vester
Vester’s system analysis delivers very good results for complex systems. With the help of the so-called intensity relationship matrix, expert knowledge is structured and new correlations become visible – a decisive step for innovative solutions.
Test-based root cause analysis
Test plans for root cause analysis pursue the goal of eliminating problems experimentally. A distinction is made between two causes of problems:
- those resulting from the production or assembly process
- and those that arise directly from the components or component combinations
An established procedure in this area is the component replacement method, which offers a methodically and statistically proven way of identifying and eliminating problems caused by components.
Our services
- Application of proven methods of root cause analysis to your quality problems
- Use of the 5-Why technique
- Use of the 6M method (Ishikawa)
- Application of Vester's intensity relationship matrix
- Problem localization and identification through statistical product analysis during production
- Application of a tried-and-tested, multi-stage problem-solving approach
- Implementation of the component replacement methodology to eliminate problems caused by components
In combination with other methods
Root cause analysis complements many other reliability engineering methods, in particular reliability testing and warranty management. In combination with design of experiments (DoE), root causes can also be validated experimentally and effectively eliminated – for a sustainable increase in quality.
