Statistical Process Control including 7 QC Tools

This chapter will describe method of using Brainstorming tool to identify most likely cause of existing problem or most likely reason for positive performance. Although this tool does not involve any statistics, it is considered as basic tool to generate ideas. This helps to begin problem identification.

Process flow chart is useful way to represent the process and understand interactions of process stages. Different methods are available to prepare flowchart. Simple process flow chart can be prepared identifying sequence of stages represented by symbol (Symbol as per type of activity). Automotive industry expects you to identify incoming sources of variation at each stage and product parameter being controlled. SIPOC method is widely used to identify process status in supply chain including parameters for monitoring effectiveness and efficiency. Value stream mapping helps in identifying constraints on process and value added / non-value added activities.

For any problem solving correct identification of root cause is essential. This chapter covers applying cause and effect diagram or Pareto analysis tools for determination of cause.

Graphs are simple tools to represent any data. For correct representation  of data, it is essential to choose appropriate type of graph. In this chapter we will discuss about selection of appropriate type of graph. Method for preparing line graph, bar graph and pie chart is discussed in this chapter.

Automotive industry expects organizations to establish process performance before selecting any process for regular production. Frequency distribution diagram is a tool to establish process performance. Histogram is used for discrete data.

Organizations need to monitor their processes for on-going performance. If process output can be measured as variable, variable control charts are useful to monitor long term process performance. In this chapter we will discuss about X-bar and R control chart, which is most commonly used variable control chart.

In many production processes resultant output is measured in attribute form. To judge process performance it is essential to monitor output results with respect to time. In this section we will discuss about 3 commonly used attribute control charts i.e. P-chart, C-chart and Demerit Chart.

Automotive industry expects organizations to demonstrate Six Sigma process performance. Hence it is essential to understand statistical measures of process and their significance.