What Are the Tools and Techniques for Quality Control?

Quality control (QC) is used in all industries to ensure that a predefined level of quality is consistently maintained. Along with quality assurance and inspections, quality control for manufacturing[1]  helps companies verify that their products meet relevant regulations and are consistent, safe, and free of defects. While quality assurance looks at the methods and techniques of production and inspections look at individual completed parts, quality control sits somewhere in the middle. It ensures that the processes and techniques used to manufacture a product are being performed appropriately.

In manufacturing, the quality control meaning extends to businesses along the entire supply chain so individual components and finished products meet or exceed those predefined standards. But what are standard quality control techniques[2] , and what are the main tools used in QC? Keep reading to find out more.

What Are the Techniques for Quality Control?

While there are myriad techniques used by manufacturing companies to maintain quality control, three of the most common include total quality management (TQM), Six Sigma, and Lean production. Companies may use one or a mix of each of these techniques, depending upon their unique needs.

Total Quality Management: Total quality management emphasizes that QC is the responsibility of each and every employee. With TQM, manufacturing companies prompt all of their employees to participate in the improvement of processes, products, and services—all with the end goal of meeting or surpassing customer needs and company-wide objectives.

Six Sigma: As a QC methodology, Six Sigma is designed to help companies improve their processes and products by finding and eliminating inefficiencies and defects. Ultimately, Six Sigma aims to ensure that there is little to no variance in the products or services being produced by refining and streamlining business and manufacturing processes.

Lean Production: Lean production in manufacturing is all about increasing productivity and reducing waste and inefficiencies as much as possible. Lean production champions techniques like organization, effective production, performance tracking, and consistent feedback loops to ensure quality control is happening constantly and consistently.

How Many Types of QC Tools Are There?

In the quality control realm, there are seven basic tools that are used for improving processes. First developed by Kaoru Ishikawa in the late 1950s and 1960s, these tools were designed to allow individuals and companies to compare and analyze data about production processes, defects, equipment issues, and more without extensive statistical and mathematical education. So what are the 7 quality control tools?

Cause-and-Effect Diagram

Also known as a fish-bone diagram, this tool is designed to show the possible causes of an issue. To implement this tool, simply identify the problem that needs to be solved and write it down. Then, identify major causes—often categorized as people, processes, materials, or equipment problems. Once all of the causes are identified, teams can determine a plan to resolve the issue.

Check Sheet

What is a check sheet in quality control? It is essentially a tool—often a basic, structured chart or form—that’s used to track data. For example, a check sheet may be used to mark down any time a defect or issue is found. Teams can use different rows and columns to identify when the issue was found, what the issue was, and how many occurred during a given time period. This can be useful in detecting patterns.

Control Chart

A control chart is used to study how business or manufacturing processes change (or remain consistent) over a given period of time. The steadier the plotted points, the more consistent and “in control” the process. On the other hand, vast peaks and valleys in a control chart often indicate an outlier that needs to be explored.

Histogram

Histograms measure frequency. Specifically, they are graphs that show frequency distributions among a certain set of data. Histograms can be used to analyze how frequently processes are running without issue, how often products are meeting customer needs, or the number of times a change in process occurred over a set period of time.

Pareto Chart

The Pareto chart aims to highlight the most important factors amongst a large number of them. For example, if a number of issues or defects are occurring along the production line, the Pareto chart can be used to identify which are occurring most often. Companies can use data gathered from a Pareto chart to identify issues in production processes.

Scatter Diagram

Also known as X-Y graphs, scatter diagrams are ideal when companies need to identify relationships. Scatter diagrams plot variable data along both the X and Y axis of a chart to identify if correlations exist and what they are. The stronger the relationship, the tighter the plotted points will cluster.

Stratification

Stratification is used to sort a large set of data points into distinct groups to better understand and analyze the information at hand. Stratification is best used when data is coming in from multiple sources or when the data must be divided to be analyzed. For example, companies may wish to use stratification when looking at when defects occur based on days of the week, shifts, or time of day to better understand an issue.

DuraMark Technologies: Your Partner in Quality Control Labels

No matter what quality control tools and techniques your company uses, you’ll likely need a way to communicate your processes, track results, or control other aspects of production. That’s where DuraMark comes in.

As the leading label supplier in North America, DuraMark works with manufacturing companies of all sizes to provide label solutions for:

• Manufacturing safety and compliance
• Manufacturing inventory management
• Variable data printing
• Product specific kitting
• Just in time manufacturing

Learn more about our enterprise solutions or reach out to us today to talk about how we can help meet your quality control needs.