Visual Inspection and Packaging

Vibriso   The main reason for the 100% inspection request was identified as the prevention of out-of-specification products reaching the customer. This is also the reason for customer complaints against the company. The products are sent to the customer unnoticed within the company and cause complaints.

In the light of the root causes of the customer's 100% measurement request, the problem symptoms of the root causes and the customer requirements, the problem is defined as follows: "Designing an effective quality control system that keeps production processes under control and increases customer satisfaction", After the problem analysis and definition phase, the issues within the scope of the project and the elements it interacts with are summarized in a tiered hierarchy in our quality control system management.

The company uses CNC lathes and milling machines and other mass production machines to process metal parts, and uses suppliers for surface preparation and other metal forming processes. While the parts to be produced are initially in the form of a metal billet or sheet, these machines process all surfaces of the billet or sheet. Furthermore, if deemed necessary, the parts are sent to the deburring department after their processing in the machines and the rough parts are treated. These metal parts and prepared rubber parts are turned into finished products by the Vulcanization process.

On these produced parts, quality characteristics such as hole diameter and wall thickness are formed. The characteristics of the parts produced in our company are examined under two different categories. First, according to customer definitions, critical characteristics and non-critical characteristics are defined in technical documents. Second, all characteristics are divided as qualitative and quantitative. The general properties and characteristics of the part are checked during incoming inspection, intermediate inspection and final inspection and it is understood whether they have in-specification values.

During measurements, tools such as shore A hardness measurement, Irhd hardness measurement, passometer, micrometer, caliper, 2d measurement projection, CMM (3d controlled measuring device) are used. As the company has a wide range of products, the sample parts where the solution approaches can be applied and where there are more opportunities for observation were determined as a result of the applied analysis and the solution approaches developed were applied on these parts.

Depending on the problem definition, the production quality control system designed for the company is aimed to provide the company; monitoring of process stability and early detection of error, continuous improvement and low cost effective measurement. The main elements of the system to be created in this direction have been determined as follows:

1 • Calibration

2 • Measurement system analysis

3 • Statistical process control

4 • Initial production approval

5 • Failure mode and effects analysis (FMEA)

6 • Improving quality management processes

To show the relationship between these solution approaches in the designed system and to provide decision support to the company regarding the quality control studies to be carried out, a flow diagram was created. This diagram also explains how the company-specific system works.

Other examinations that can be performed using the Initial and Final control sampling method are determined as entry and final control. In initial control, 100% control does not add value to production. Before the final control, the proposed system will provide the necessary controls during production. Hence, applying an acceptance sampling plan in both the entry and final control was deemed sufficient. For these reasons, ISO/DIN standards, which were previously used, were selected as the most appropriate method for acceptance sampling. In this context, with the help of Microsoft Office Excel Macro and ERP system, there is a system that keeps historical data according to the acceptance levels determined to be used in the initial inspection and creates an acceptance sampling plan suitable for the user and keeps historical data.

In this study, an effective quality control and improvement system was designed for a rubber company engaged in technical production. This quality control system consists of Measurement System Analysis, Statistical Process Control Charts, Failure Mode and Effects Analysis, Inspection Planning based on a mathematical model and Acceptance Sampling.

The solution approaches that constitute the parts of the designed quality control system and their interaction with each other on the flow diagram have been explained in detail in our company with the manuals prepared. Recommendations are made for improving the system broadly to include other approaches to total quality such as human resource training, lean production and quality by design. This system was also supported by company officials. The proposed system can be used through adaptations by many companies with similar characteristics. Following this study focusing on the production system, other quality control approaches that complement and enhance the effectiveness of the developed quality control system should be evaluated. Among these, implementing process designs, training employees to increase their quality improvement knowledge and skills, and initiating project-based improvement activities can be suggested as priority approaches.