What is Quality Control? 4 Common Methods What is quality control? Why is quality management important in manufacturing? Find out with Viindoo

What is quality control?

Quality Control (QC) focuses on ensuring that quality requirements are met. It is the process of controlling and evaluating factors involved in the production of products and services, including people, machines, materials, methods, information and the work environment..

The Importance of Quality Control

Quality control is important because:

• Quality control helps employees maintain a focus on quality throughout the production process, helping the company consistently achieve the desired level of quality.
• Quality control processes detect and correct substandard items, thereby reducing production costs.
• Quality control ensures products are free from errors or defects, enhancing customer satisfaction.
• High quality products that meet the organization's quality control requirements demonstrate commitment to meeting customer needs, improving corporate reputation.
• When employees see they are producing products of value to consumers, overall company morale improves.
• Quality control processes help streamline and improve production processes, increasing efficiency and productivity.
• Consistent quality control helps build a reputation for quality, attract new customers and increase sales.
• Quality control helps companies optimize resource utilization, minimize product and material waste, and increase production efficiency.

Four common quality control methods

Taguch method

The Taguchi method of quality control focuses on research and development, design and product development to minimize the occurrence of defects and failures in the manufacturing process. This method emphasizes that design is more important than the manufacturing process, with the goal of eliminating manufacturing variances before they occur.

X-Bar Chart

The X-Bar chart is a popular tool in quality control that helps track the level of variance of the tested attributes. The y-axis on this chart shows the acceptable level of variance, while the x-axis tracks the test samples. Analyzing the variance pattern through the X-Bar chart helps determine whether errors are occurring randomly or systematically, thereby suggesting appropriate improvement measures.

100% inspection method 

100% inspection is a comprehensive quality control process that involves reviewing and evaluating every part of a product to eliminate defects. This process requires manufacturing process data and inventory analysis software to ensure efficiency.

However, this approach can be challenging due to high costs and the risk of destabilizing the product. For example, applying 100% inspection to organic strawberries can result in bruising or spoilage, affecting the distributor’s ability to sell.

Six Sigma Method

6 Sigma is a quality management and manufacturing process improvement method that aims to reduce deviation. This method measures and analyzes data on product quality and manufacturing processes to determine the causes of defects and find solutions to overcome them.

With high precision, 6 Sigma allows only about 3.4 defects per million products. 6 Sigma focuses on optimizing and continuously improving the manufacturing process, ensuring product quality from the beginning and preventing defects, instead of just dealing with defective products.