Analytical sheet (also control sheet) is extremely helpful in the process of collecting and organizing information, which is related to the specificities of the product, or process. Data about specific activities is entered into sheet to allow the study of product or process. Information about the frequency of occurrence of the events and its the place is important to further sheet analysis.
With the help of an analysis it is possible to collect specific data that can help find answers to questions such as:
- How did analyzed the problem occurred?
- How many times a specific problem happened?
- Where the problem is located?
- What is the cost of the errors?
The data can be placed into the sheet in the form of simple graphic characters. The control sheet should be constructed to be clearly seen for what purpose serves. This is a very effective and simple utility that primarily serves to collect and organize data from the performed measurements and observations.
Very often the tool is used to monitor the process or changes that were introduced to the process by the corrective or preventive actions. The quality managers use several types of control sheets, that help analyze:
- specific features of the numerical distribution of the product or process,
- frequency of occurrence of defects,
- location of defects,
- the cost of the occurrence of faults and defects,
- the causes of defects and faults.
There are several supporting tools that can be used to collect and analyze data related to a specific product or process. Some of the most common include:
- Pareto Chart: This chart is used to identify the most common causes of defects or problems. It is a bar chart that shows the frequency of occurrence of each problem, with the bars arranged in descending order. The Pareto principle states that 80% of the problems are caused by 20% of the causes, so the chart helps to identify the most significant problems to focus on.
- Control Chart: This chart is used to monitor and control a process over time. It shows the average and range of a process over time, as well as upper and lower control limits. Any data points outside of these limits may indicate that the process is not in control.
- Fishbone Diagram: Also called an Ishikawa diagram, this is a tool used to identify the root cause of a problem. It is a diagram that looks like a fishbone, with the problem being represented by the head of the fish and the causes being represented by the bones. It is used to identify the various factors that contribute to a problem.
- Scatter Diagram: This is a chart that plots two variables against each other, with the aim of identifying any correlation between the variables. It is used to identify the relationship between two factors that may be causing a problem.
- Histogram: This chart is used to show the frequency distribution of a variable. It is a bar chart that shows how many data points fall into each category. It is useful for identifying patterns or outliers in the data.
- Flowchart: This is a diagram that shows the steps in a process and how they are connected. It is used to identify bottlenecks or inefficiencies in the process, and to help identify the root cause of a problem.
In summary, an analytical or control sheet is a tool used to collect and organize data related to a specific product or process. It can help track and analyze the frequency, location, and cost of defects or problems, as well as identify the causes of those problems. Quality managers use different types of control sheets to analyze various aspects of the product or process, such as numerical distribution, frequency of defects, and cost of defects. The data is typically entered in the form of simple graphic characters and the sheet is designed to be clear and easy to read.
- Salih O. Duffuaa, Mohamed Ben‐Daya, (1995) Improving maintenance quality using SPC tools, Journal of Quality in Maintenance Engineering, Vol. 1 Iss: 2