Strahinja Stojanovic In order to implement IATF 16949, the organization needs to develop Control Plans at the system, subsystem, component, and/or material levels for the relevant manufacturing site and all product supplied.
What is a Control Plan and when is it used?
A Control Plan is a written description of the system for controlling parts and processes. It provides a written summary description of the systems used in minimizing process and product variation. Sketches, as necessary, can be attached to the Control Plan for illustration purposes. However, it doesn’t replace information contained in detailed operator instructions.
In effect, the Control Plan describes the actions required at each phase of the process, including receiving, in-processes, out-going, and periodic requirements to ensure that all process outputs will be in a state of control. During regular production runs, the Control Plan provides the process monitoring and control methods that will be used to control characteristics. Because processes are expected to be continually improved and updated, the Control Plan reflects a strategy that is responsive to these changing process conditions. The Control Plan helps ensure that quality is maintained in a process in the event of employee turnover by establishing a standard for quality inspection and process monitoring.
The Control Plan is maintained and used throughout the product life cycle. Its purpose in the early stages of the product life cycle is to document the initial plan for process control. Subsequently, it guides manufacturing in how to control the process and ensure product quality. A single Control Plan may apply to a group or family of products that are produced by the same process at the same source.
Ultimately, the Control Plan should be a living document, reflecting the current methods of control, and the measurement system used. The Control Plan is updated as measurement system and control methods are evaluated and improved.
What does the standard require?
The standard requires the Control Plan to include the controls used for manufacturing process control, including verification of job setups, first off/last off part validation, methods for monitoring of control exercised over special characteristics, customer-required information (if any), and a specified reaction plan for when a nonconformity is detected or when the process becomes statistically unstable or not statistically capable.
In addition, Annex A of the standard defines requirements for the Control Plan in more detail. The Control Plan covers three distinct phases, as appropriate:
Prototype – a description of the dimensional measurements, material, and performance tests that will occur during building of the prototype. If the customer requires, the organization may develop a Control Plan for the prototype.
Pre-launch – a description of the dimensional measurements, material, and performance tests that will occur after prototype and before full production. Pre-launch is defined as a production phase in the process of product realization that may be required after the prototype is built.
Production – documentation of product and process characteristics, process controls, tests, and measurement system used during mass production.
And, finally, the standard requires the organization to review the Control Plan in cases when:
- the organization determines that it has shipped nonconforming product to the customer
- when any change occurs affecting the product or process
- after a customer complaint and implementation of associated corrective actions
- at a set frequency based on risk analysis
In some cases, the organization needs to get approval from the customer after review or revision of the Control Plan.
How to develop it?
Development of the Control Plan requires a multidisciplinary team and the utilization of all available information in order to get a better understanding of the process, such as:
- Process flow diagrams
- FMEA (for more information, see: What is FMEA, and how to apply it in IATF 16949)
- Lessons learned from similar parts
- Team’s knowledge of the process
- Design reviews
- Optimization methods
Additionally, Annex A of the standard defines the minimum content of the Control Plan and the information required is divided into the following groups:
- General data
- Product control
- Process control
- Methods
- Reaction plan
Benefits of the Control Plan
The benefits of the Control Plan can be sorted into the following categories:
Quality – The Control Plan reduces waste and improves the quality of products during design, manufacturing, and assembly. This structured approach provides a thorough evaluation of the product and process. Control Plans identify process characteristics and help to identify their sources of variation (input variables), which cause variation in product characteristics (output variables).
Customer satisfaction – Control Plans focus resources on processes and products related to characteristics that are important to the customer. The proper allocation of resources on these major items helps to reduce costs without sacrificing quality.
Communication – As a living document, the Control Plan identifies and communicates changes in the product/process characteristics, control method, and characteristics measurement.
The Control Plan can be a very effective tool for reducing the amount of scrap generated by a process. It can be very useful at improving quality and helping contain any non-conforming product prior to it leaving the work cell. It is most effective when incorporated into a larger quality plan. The Control Plan is the same as any other tool, in that to get the most value – you must know how to use it properly.
Use this free IATF 16949:2016 Implementation Diagram to manage IATF 16949:2016 Control Plan implementation.
