When we talk about quality in production, we come across a variety of terms. They range from quality management and quality assurance to quality testing and quality control. They are often used interchangeably, but the crux of the matter is that they all have their own meaning and relevance.
In this article, we will focus on quality control and its actual meaning. Quality control refers to procedures and processes that are used to check a product or service against predefined quality criteria. Such requirements can be, for example, specific production specifications, certain standards or customer requirements.
It is important to note that quality control has a clear product-related focus. It is specifically about checking a (partially) manufactured product - with the aim of identifying errors, defects or deviations.
Incidentally, you will often come across quality control as a quality inspection in research. However, we are talking here about quality control as an internal production process within quality assurance, whereas a quality inspection can also be carried out by external service providers.
The tasks of quality control all revolve around - you guessed it - ensuring product quality in accordance with predefined specifications. This includes
In a nutshell: You can either check random samples or everything. What are the differences?
Random sampling
Random sampling is particularly suitable for mass production. With random sampling, you check the quality either randomly or according to a predefined number of products or shots. You define in advance how large the number of products to be inspected is and how many defects or faults per sample are acceptable.
One hundred percent inspection
If you manufacture in particularly small batch sizes or customized products, it makes sense to test every product (or service). Of course, you must also define criteria in advance according to which the products are tested. The only difference is that you check every product and may invest more time in an in-depth inspection.
Targeted quality controls pay off for your company on many levels. And these range from the optimization of your own processes and procedures to your competitiveness.
There is actually no real argument against sensibly established quality controls. On the contrary: there are a few more arguments that you should bear in mind when deciding on an effective quality control system:
Of course, quality controls can initially incur costs and require technological adjustments. However, the benefits you derive from established testing processes are significantly greater.
Quality controls can be found at various points in the production process - from incoming goods to outgoing goods. Let's take a closer look at the four basic checks.
As the name suggests, a quality check is carried out on the incoming product or component at goods receipt. The aim is to ensure that the outgoing product complies with the specifications and that there are no errors here that may not be traceable later.
In-process quality control (IPQC) involves continuous quality checks during production - i.e. everything that occurs between the input product and the end product. IPQC is particularly relevant in the case of strict regulations or requirements.
With Final Quality Control (FQC), we have arrived at the last inspection and the final tests of the product before delivery. The aim here is to ensure that the necessary standards for the customer or the market have been met.
After the final inspection, the product is packaged and provided with the necessary documents. Outgoing Quality Control (OQC) checks that the packaging is free of defects and that all relevant documents are enclosed.
All industries can benefit from quality control. However, there are some industries that are particularly reliant on quality control. In principle, this applies to all industries that manufacture products or offer services that pose a potential risk of harm to people. These include, for example
For companies in the medical and food sectors in particular, guidelines have already been established that stipulate detailed quality standards. These include, for example:
In order to optimally comply with these respective standards, companies need reliable quality assurance processes and - in practice - the corresponding quality controls.
Step 1: Define quality standards
Quality standards must first be defined as a quality assurance measure so that the inspector knows what is to be inspected and how. To do this, quality assurance must
Step 2: Production monitoring through regular quality checks
The next step involves continuous monitoring of the production processes from a quality perspective. For example, you can have visual inspections carried out by the worker using sensors or cameras. Quantitative tests and (performance) measurements - for example electrical tests, chemical analyses or stress tests - are also an effective means of quality control.
The aim of quality control is to identify deviations and errors by comparing the recorded results with the specified quality standards. If errors occur, you initiate appropriately defined measures to rectify them (rework, training, etc.).
Does everything fit? Then quality control releases the product as a good part.
Step 3: Documentation
Of course, quality control also includes recording the results. In such a protocol, the following are recorded, among other things
Step 4: Support continuous improvement processes
In this step, you move from quality control to quality improvement and use the findings from the inspections to identify possible trends and promote continuous improvement processes. This in turn has a positive impact on your quality standards.
There is a suitable solution for everything, including quality management. Computer-aided quality assurance - or CAQ for short - or quality management software facilitate the collection and evaluation of quality-related data. This data can in turn be used to derive conclusions for the further planning of quality assurance and quality control measures.
With a worker assistance system, you can guide employees digitally through inspection steps or complete inspection plans. As part of the digital work instruction, you specify standardized quality data and record collected or entered data directly in the system.
The Internet of Things describes the networking of devices and systems - including in production. Using networked sensors, cameras or controllers, you can record data in real time and detect and rectify anomalies or quality deviations more quickly.
Intelligent algorithms enable the centralized or decentralized evaluation of large data sets. They can predict possible errors or system failures that could affect the final quality of the product.
Yes, we've already talked about the benefits of quality control above. But we have another bonus for you: digitized quality control offers further advantages:
For effective quality control, it is best to use a digital system - especially if you want to hand over test steps to your employees in production and assembly. Our weasl worker assistance system provides the perfect basis for this.
With weasl, you can implement inspection plans as easy-to-understand, multimedia-supported step-by-step work instructions. You can use a role-rights system to define which inspections can be carried out by a worker and which can only be carried out by trained inspection personnel. In this way, you enable your workers to carry out worker self-inspections and strengthen their quality awareness.
You can easily validate quality-relevant entries with weasl, for example by highlighting the relevant input fields in color. If an input value exceeds the tolerance range, the worker is informed by a red message text, for example. You can also prevent incorrect entries through standardization - for example, by only allowing measurements in defined numerical ranges and units.
weasl communicates with your systems, tools and test equipment. If the required inspection tools are connected to weasl, your workers can automatically read out inspection data and transfer it to the system. Communication - for example in the event of queries or support requests - also takes place directly in the system thanks to the feedback function.
With weasl, you can automatically record and document all work steps, results and input values. This prevents media disruptions and the resulting errors and loss of time. At the end of a work or inspection plan, weasl automatically generates a log with all data and information.