The control chart is an effective tool to achieve statistical control of a process and to give the person who is closest to the process the ability to evaluate the quality performance for which he or she is directly responsible. The control chart does not actually control anything;
it simply serves as the basis for action.
This chart is valuable only if timely actions are taken when required. In explaining the reasons for the popularity of control charts in industry, Montgomery (2005) included the following items:
1.Control charts are a proven technique for improving productivity.
2.Control charts are effective in defect prevention.
3.Control charts prevent unnecessary process adjustment.
4.Control charts provide diagnostic information.
5.Control charts provide information about process capability.
The control chart is a reliable indicator of the two types of process variations (chance cause and assignable cause),and thus minimizes the amount of unnecessary searching for causes with the process when no assignable cause is present.
The control chart helps to get a process into a state of statistical control,after which the inherent variation can be further reduced by a change in the process itself (training,methods,materials,tooling, etc.)to:
1.Increase the yield reducing non-conforming product.
2.Cut the cost per unit by eliminating scrap and rework.
3.Increase productivity by increasing the throughput of the acceptable product with no increase in capacity.
Finally,control charts speak in the language of statistics; this provides the common ground for consistent communications about quality between the various functions in the plant [Hamilton (1993)]. To use control charts, one begins by following these six key steps:
1-Define the objective.
2-Analyze the production process.
3-Choose the characteristics to control.
4-Determine the proper control chart.
5-Collect the data.
6-Interpret control chart run rules.
Define the objectives
Control charts are used as part of the central plan. It is very important that the early steps of gaining management commitment, putting together a management steering group, and training management, technical, and operations personnel are all followed in the quality improvement program before introducing statistical methods such as control charts. When the appropriate ground has been set and work areas are ready to implement such methods, then the objectives of such a program should be well-known by all of the people who are participating.
Analyze the production process
The process should be analyzed in terms of the important factors operating within it (people, equipment, materials, etc.), taking into account its relationship to processes upstream and the process/user requirements downstream. The analysis should involve the technical, operations, and the quality people who are experienced with the process, with the specifications that must be met, and with the major nonconfermance challenges. This will ensure that the analysis is comprehensive, and it will create the groundwork for the operation necessary to make the control chart program effective.
it simply serves as the basis for action.
This chart is valuable only if timely actions are taken when required. In explaining the reasons for the popularity of control charts in industry, Montgomery (2005) included the following items:
1.Control charts are a proven technique for improving productivity.
2.Control charts are effective in defect prevention.
3.Control charts prevent unnecessary process adjustment.
4.Control charts provide diagnostic information.
5.Control charts provide information about process capability.
The control chart is a reliable indicator of the two types of process variations (chance cause and assignable cause),and thus minimizes the amount of unnecessary searching for causes with the process when no assignable cause is present.
The control chart helps to get a process into a state of statistical control,after which the inherent variation can be further reduced by a change in the process itself (training,methods,materials,tooling, etc.)to:
1.Increase the yield reducing non-conforming product.
2.Cut the cost per unit by eliminating scrap and rework.
3.Increase productivity by increasing the throughput of the acceptable product with no increase in capacity.
Finally,control charts speak in the language of statistics; this provides the common ground for consistent communications about quality between the various functions in the plant [Hamilton (1993)]. To use control charts, one begins by following these six key steps:
1-Define the objective.
2-Analyze the production process.
3-Choose the characteristics to control.
4-Determine the proper control chart.
5-Collect the data.
6-Interpret control chart run rules.
Define the objectives
Control charts are used as part of the central plan. It is very important that the early steps of gaining management commitment, putting together a management steering group, and training management, technical, and operations personnel are all followed in the quality improvement program before introducing statistical methods such as control charts. When the appropriate ground has been set and work areas are ready to implement such methods, then the objectives of such a program should be well-known by all of the people who are participating.
Analyze the production process
The process should be analyzed in terms of the important factors operating within it (people, equipment, materials, etc.), taking into account its relationship to processes upstream and the process/user requirements downstream. The analysis should involve the technical, operations, and the quality people who are experienced with the process, with the specifications that must be met, and with the major nonconfermance challenges. This will ensure that the analysis is comprehensive, and it will create the groundwork for the operation necessary to make the control chart program effective.
ليست هناك تعليقات:
إرسال تعليق