RICOH manufacturing DX Practical Lab
Quality Control in Manufacturing sites.
Explanation on its contents, challenges, and key points for success.
Quality control is a vital process in the manufacturing industry. Manufacturers are required to reduce the incidence of defective products to keep manufacturing costs down, and to maintain reliability by assuring the quality of products to clients. In this section, we will introduce the overview and importance of quality control in the manufacturing industry and explain its challenges and the key points for success.
Quality control in the manufacturing industry involve controlling the manufacturing process to ensure that the quality of manufactured products is maintained at a certain level and inspecting and confirming that products to be shipped meet quality standards. It may be called “QC” in short as well.
In addition to inspecting the products themselves, another important task of quality control is to identify the causes of defective products to develop measures to prevent their recurrence when they occur. To reduce the number of defective products, quality control also includes establishing a mistake proof environment, such as setting up work procedures and preparing jigs to prevent human errors. Furthermore, Quality control may include the training of employees to raise their awareness of quality control and developing human resources capable of producing products of reliable quality.
Quality assurance simply means “assuring that the company's products and services have a certain level of quality,” while quality control refer to “managing the quality of products.” Therefore, Quality control can be said to be a part of quality assurance.
In the event of a defective product or a complaint, the quality assurance department, in cooperation with the sales department in dealing with the customer, instructing the quality control department to identify the cause of the problem. The quality control staff reports the identified causes and takes preventive measures such as process improvement.
When quality control is inadequate in the manufacturing industry, defective or inferior products are delivered to clients and consumers as is. This is a major disadvantage for both the manufacturer and the client or consumer.
If the poor assembly quality continues, the company's credibility will be damaged, and products produced in that factory will not sell well. In addition, some products may cause injury or accidents to consumers who use them, and the company may be obliged to pay compensation for damages, which could be so severe that it would be impossible to continue business itself.
Thorough quality control will prevent the occurrence and shipment of defective products, and continuing to provide high-quality products will increase the reputation of the company. Quality control is essential for securing regular customers and maintaining stable operations.
Quality control in the manufacturing industry can be divided into three main categories.
The work processes for manufacturing products are standardized and controlled for each line. In general, data is collected and analyzed using the “Seven QC Tools (check sheet, Pareto chart, control chart, histogram, characteristic factor chart, scatter diagram, and stratification)” to visualize problems on the shop floor.
To avoid confusion and the production of defective products whenever the worker changes, it is important to standardize the work process by creating manuals. This will create a stable work line that does not rely on each worker’s efforts. Process control also includes education and training to ensure that employees have the technical skills to assemble products at a certain level of quality.
Equipment used in daily operation is subject to wear and deteriorate over time, so periodic inspections and maintenances are also vital to maintain product quality.
This is the inspection which ensures that the products meet a certain quality standard. The criteria are based on the Japanese Industrial Standards (JIS) and international standards (ISO standards). In addition, companies may have their own strict standards as well.
Inspections can be divided into the following categories. “Acceptance inspection”, which is an inspection conducted to check for problems in raw materials, “in-process inspection” conducted at each process, “finished product inspection “conducted at the end of the assembly, and “outgoing inspection” to check for any final defects before shipment. In these processes, non-destructive inspections are commonly conducted, but “destructive inspections” may also be added to verify the strength and durability of the product.
Quality improvement is performed to prevent the recurrence of defective products. When defective products are delivered, manufactures are required to present the client with countermeasures to assure the problem will not reoccur, in order to continue the production.
The QC process shall be carried on according to the “QC Story:” Theme Setting, Current Status, Goal Setting, Cause Analysis, Countermeasure Planning, Countermeasure Implementation, Effect Measurement, Reflection and Future Policies, and Standardization.
Quality control in the manufacturing industry involves the following issues.
The causes of quality variation can be attributed to the fact that the work is often performed by individuals with different skills, human error, and variations in the quality of raw materials. Variations in quality can lead to an inability to provide a stable supply, which can damage the trust of clients and consumers.
In complex processes which require skilled workmanship, the skilled worker often tend to be assigned to that process repeatedly. As the process becomes individualized, it may become harder to maintain quality, when the skilled worker takes a leave of absence or retires. Therefore, it is necessary to standardize the work and to make the work process approachable to anyone.
Due to the declining birthrate, aging population, and the deviation between the popularity in each industry, there is an ongoing shortage problem of manpower in the manufacturing field. Without sufficient manpower, necessary processes cannot be carried out and a stable supply chain cannot be maintained. In addition, it will become harder to maintain certain skills as they cannot be passed down to the next generation.
When a problem arises, the quality control department needs to inform the field and instruct them to improve. Those who receive suggestions are likely to feel frustrated and may rebel against the orders if not cared. To ensure thorough quality control, we must build a good relationship with the manufacturing department.
The key to successful quality control in the manufacturing industry will be explained from three perspectives: process control, quality inspection, and quality improvement.
Here are some key points for successful process control.
Create an operation manual.
Creating an operations manual reduces the amount of discretion left to the operator and helps stabilize quality. When creating the manual, write down the procedures in as much detail as possible, and explain the meaning of each process. Once the significance of the process is understood, it will be easier to work on it in a positive manner.
Reduce man-hours on site.
Review the processes on site to eliminate as much waste as possible and reduce the number of man-hours. Reducing man-hours not only saves costs and labor, but also helps in quality control by reducing the chance of mistakes.
The following are some of the key points for successful quality inspections.
Improve the work environment.
The work environment includes a variety of factors such as temperature, humidity, air quality, illumination, and wind speed. Simply improving the work environment, for example by optimizing the position and brightness of light sources, can make products easier to see and reduce errors. Consider what factors in the actual process affect the manufacturing process while trying to improve the work environment. In the inspection process, it is especially important to create an environment that facilitates the detection of defects.
Introduce a quality management system.
In a broad sense, a quality management system (QMS) refers to a system that continuously improves the quality of products and services, and it can also refer to a quality management system that utilizes digital technology.
The contents of quality management systems in introducing DX vary by manufacturer and package, but they include a variety of functions, such as barcode scanning to detect part number differences, recording functions to enable traceability, and process control through image recognition. Compared to handwritten or manual input, there is no possibility of error, and the introduction of such systems can be expected to improve quality and prevent defective products.
For successful quality improvement, it is important to keep the following points in mind.
Improve workers' skills.
When workers' skills are improved, the risk of failure and defective products in difficult processes can be reduced. For example, basic skills such as welding and painting should be acquired through education and training. Basic training is also necessary to raise awareness of the need to comply with processes and prevent the occurrence of defective products.
Eliminate waste in operations.
Many operations are wasteful, such as non-urgent reporting and inspections. The more processes there are, the more chances there are for mistakes to occur. Therefore, reducing the number of procedures as much as possible by automating what can be automated and eliminating unnecessary tasks.
Here are two recommended systems for quality control in the manufacturing industry.
An all-in-one system of camera, image recognition, and software. All you need is a mouse, keyboard, and monitor to use. The system automatically checks the assembly status of similar parts, missing parts, and work order based on image recognition. The system can record actual results such as serial numbers of parts and working hours, as well as images of work results, which enables traceability and is useful for work analysis. Image recognition ensures that the correct operation or part is recognized before proceeding to the next step.
This model has the same functions as the RICOH SC-10A. In addition, a touch panel monitor can be installed, making it easy to use on site without a mouse or keyboard.
It is no exaggeration to say that quality control is the most important department in the manufacturing industry that delivers products to the world. To manufacture stable, high-quality products and continue to gain trust, we should make good use of digital technology to ensure thorough quality control.
