Quality Control in Custom Molded Rubber Parts: Ensuring Excellence |

Custom moulded rubber parts are one of the most versatile and cost effective types of manufacturing you can get, from automotive, aerospace through to extreme sports and more. However, ensuring high-performance and longevity from these components requires stringent quality control processes. These are no new terms, you would have already got read aboutit all here, as each of these articles focuses on a key aspect ofquality that you should not compromise when looking for custom mouldedrubber parts, hoping you can build processes better with best qualityend-products in mind.

Design stage quality control

To have a quality final product, the design stage is very important. At this stage we would need to think about:

1.1 Material selection: The correct rubber material is critical for the desired properties. Consideration must also be given to the component environment (temperature, pressure, contact media, etc.) and the desired physical properties (tensile strength, hardness, wear resistance, etc.) and chemical properties (oil resistance, corrosion resistance, etc.). A detailed material database will be established to record the performance parameters of many rubber materials. Designers can be selected from this database.

1.2 Mold design The design of the mold is directly related to the quality of molding of rubber parts. The CTE Selection will depend on the raw material CTE selection, for mold structure we need to consider the flow of the rubber filling evenly, reduce bubbles and voids. Good design of exhaust system for the molding process will be able to smooth gas generate discharge. Dimensional accuracy and surface finish of the rubber parts will directly depend on the accuracy and surface finish of the mold. Work with advanced mold design software to simulate and anticipate possible issues with the mold process that could see enhancements in the design phase.

(1.3) Product design: The design of the product should fully consider the characteristics of the molding process, avoid too complex or too sharp structure, reduce stress concentration, and demoulding difficulty. Use of good die slope, easy to remove good products, reduce deformation and damage. This way, the next quality inspection can be done with the correct labeling of the products.

Quality control at production level

The control of the production process is the key link to ensure the quality of rubber parts. A perfect quality management system should be developed, covering all production processes.

2.1 Qualified inspection of rubber raw materials: The strict inspection of all rubber CAS from entering the line (composition, purity, viscosity, etc.), professional testing equipment (vulcanizer, Mooney viscometer, etc.) for raw material testing, to ensure that raw material quality qualified. Strongly eliminate unqualified raw materials and not allow them to appear in production.

2.2 Control of molding process: The molding process temperature, pressure and time are the most important parameters affecting the quality of rubber parts. These parameters are tuned with precision limits, so that some fraction of the rubber can be vulcanised properly to achieve the required physical properties. Then an automatic control system is used to continuously monitor and adjust these parameters, capable of reducing human quality deviations. In short, cut quality data required to make detailed process parameters record to provide the basis for later quality analysis of data.

2.3 On-line inspection: Random sampling of semi-finished products during the production process to check whether the dimensions, appearance and performance meet the requirements. Then start addressing problems in production with advanced practices and techniques. Inspection can be a full monitoring for special products or key processes, ensuring the quality of products.

2.4 Regularly maintain and calibrate molding equipment: In order to ensure the normal run of the equipment and the accuracy of the equipment, regularly to the molding equipment for maintenance and calibration. Mold can be very not only the application, more importantly, it should be regular maintenance, including cleaning, lubrication, repair and so on, in order to prolong the service life of the mold, to ensure the molding quality of the product.

Third: Final Product Inspection & Quality Testing

Final inspection on completed products is the last line of defense to verify that qualified rubber parts leaving the factory.Establish complete inspection practices and norms.

3.1 Appearance inspection: All finished products can only be delivered after appearance inspection to check for quality defects such as bubbles, cracks, deformation and impurities. After inspection, the defects identified in the visual inspection are classified and recorded and detailed inspection is done by using some auxiliary tools such as magnifying glass.

3.2 Three-dimensional measurement: The main dimensions of the product are measured with calipers, altimeters, CMM and other precision measuring tools to ensure that the dimensional accuracy meets the design requirements. Tools of quality such as control charts11.

3.3 Performance test: Perform corresponding performance tests based on the use and performance requirements of the product, such as tensile strength, hardness, compression permanent deformation, oil resistance, heat aging, etc. Standardized test methods are used to provide test accuracy and reproducibility of test results.

3.4 Non-destructive test: Non-destructive testing technology is used for inspection of some important parts, such as, ultrasonic detection, X-ray testing, etc., to check whether there are internal defects. Non-destructive testing can identify the hidden internal dangers without damaging the product and enhance the product's safety and reliability.

Fourth, Enhancing the quality and constant optimization

Quality assurance, however, is not just a one-time thing — it’s an ongoing cycle of improvement and optimization.

4.1 Data analysis and statistics Statistical analysis of different data generated in production process to determine the key factors in affecting quality. As SPC and other means can be adopted to monitor process stability, abnormalities can be found and dealt with in time.

4.2 Root cause analysisBefore any quality issue occurred, RTCA was required to find out the root cause of the problem and formulate corresponding corrective measures. Investigating the problem in further detail using techniques like 5 Whys & Fishbone diagram.

4.3 Continuous Improvement: Generate a continuous improvement culture and give employees the initiative undertaken to enhance quality. Discuss lessons learned on the process and discuss regular quality meetings that will focus on improvement aspects. PDCA (Plan-Do-Check-Act) cycle, continuous quality control improvement and other methods.

4.4 Getting input from the customers: getting to know customers through an interview to know their quality requirement and expectation from the products. Guide quality improvement initiatives and plans based on customer feedback.

V. Conclusion

We are doing quality control of the custom moulded rubber parts from design, production, inspection and improvement. Through stringent design control, process control, evaluation of finished product, and upgrading, the efficiency can be enhanced to meet the customer requirement. We have a continuous growing automation and intelligent of technology that will help to simplify a better quality control process in the future hopefully.