Many businesses, including online sellers, use quality control tools to assist, monitor, and supervise their products. Quality Control tools are methods or techniques that are used to sort out quality issues that may arise. There are numerous types of tools that someone can use.
There are five management tools for quality control that are the most popular namely:
1.Flowcharts,
2. Checklists
3.Cause-Effect Diagram
4. Pareto chart
5. Control charts.
Different tools are used for numerous problem-solving alternatives, and someone can use many of the tools in various ways. With these tools, you can, as the name suggests, control the quality of your product and also come up with different ways on how to deal with situations where the quality of your product is not what you expected. This article will also show you how these tools can help you maintain good quality for your product.
- FLOWCHARTS
We are all aware of “Flowchart” from our school or college moments. A flowchart is a design that illustrates a workflow technique, or a step-by-step way related by arrows in different scenarios.
HOW TO USE A FLOWCHART
Flow charts define the steps of a procedure. Flowcharts also provide an image of what the process looks like and sheds light on its problems. For example, Your product is inspected and now you have to decide whether to accept the product quality or reject it. Let the flowchart help you decide by using the simple guide below.
- Products are inspected
- Option a) If products meet standards:
Actions: label, process product, assemble, do the final inspection.
- if passed final inspection,
Actions: then pack and ship the product.
- If the failed final inspection
Action: product rework.
- Option b) If the product does not meet standards:
Actions: Product rework.
This is simplified further in the flowchart below.
As seen above, the flowchart will help you decide whether or not to accept the quality of the product by basing the decision on factual information given in the inspection report. Using a flowchart will help you maintain your decision on each product batch you inspect. As a result, the overall quality of your product will be maintained as good quality.
2. CHECKLISTS
A quality inspection checklist is a tool that you use to help your third party inspection company know your expectations and standards that you have set for your product. It also helps inspection companies to know exactly where to pay more focus during the inspection.
HOW TO USE AND CREATE A CHECKLIST
Step 1: Give your product details as to what the inspection company should focus on
Step 2: For each product detail, classify the defects into 3 groups- major, minor, critical.
Step 3: Give your checklist to the inspection company.
A simple checklist is given below.
From the checklist above, the product details have been categorised as to what constitutes a major, minor or critical defect in the eyes of the seller. This will help the inspection company prioritise those areas during an inspection.
- CAUSE-EFFECT DIAGRAM
A cause and effect diagram, also known as a fishbone diagram, shows the many possible causes of an issue. A Cause-Effect diagram or an Ishikawa diagram is a diagram that shows the causes of an event and is often used in manufacturing and product development to outline the different steps in a process, demonstrates where quality control issues might arise and determine which resources are required at specific times.
HOW TO USE A CAUSE-EFFECT DIAGRAM
To use this tool,
- Draw a horizontal line, and at the end of it, right the main problem. For example, low product quality is the main problem.
- Next, you will list the primary reasons for the problem as branches off that horizontal line that has the main problem
- Separate the causes into categories e.g people, procedure, materials, and equipment.
- Once you identify all possible causes, develop a modification plan to solve the problem.
These steps are indicated in the diagram below.
4. PARETO CHART
A Pareto chart is a bar graph showing the most crucial number of frequencies to the smallest. For example, The Pareto chart can help determine the quality of your product based on the frequency of a specific type of defect that is found during an inspection.
HOW TO USE A PARETO CHART
Based on our example above,
Step 1: Place your defects against the number of product batches ( in this case we will call them observations) that have been inspected.
Step2: Shade the areas where the defects meet product batches.
Step3: Now plot the percentage of defects in the graph.
Step 4: Join the dots that you have plotted.
When you look at the number of defects from the largest to the smallest occurrences, it is easy to prioritize improvement efforts. Pareto Charts measure the various sources impacting one base. In the picture, You can see the number of defects Vs Observations VS the percentage of defects. We can see the highest number of observations being 8 has the highest defects being 90% of total defects. The most significant problems stand out and can be targeted first. In this case, we will target the 6thObservation group.
- CONTROL CHARTS
A quality control chart is a graph that depicts whether sampled products or processes are meeting their intended quality specifications. If not, the chart will show the degree by which they vary from specifications.
HOW TO USE CONTROL CHARTS
The steps are outlined below.
Step 1: On the vertical axis, put down the number of products that were accepted without defects.
Step 2: On the horizontal axis, write down the total products in each consignment
Step 3: Set your upper control limits and your lower control limits.
Step 4: Plot the graph
Step 5: Join the plotted points on your graph
Step 6: Are the products within the limit? if below the lower limit, then quality is low.
Step 7: If within, then you are average.
Step 8: If it is high then you have excellent results.
These steps are illustrated in the control chart below. I
From the chart we can see that the quality of the product is not very good as it ranges between poor quality and average quality.
REVIEW
We have analyzed five of the essential Quality Management and Improvement Tools here in this article. Each of these quality tools has unique advantages for specific problems. Once you understand how to use these tools, you can adapt them according to your needs.
Also, understanding quality control tools can help you understand the recommendations that your inspection company gives in the inspection reports.