In the ever-evolving landscape of manufacturing and production, it’s essential to have efficient quality control measures to ensure the efficiency of output.
In fact, the injection molding process for manufacturing provides manufacturers with multi-stage processes from material selection to mold design, process parameter monitoring, and post-production testing.
The outcome? The aim is to ensure that every part meets the customer’s desired results and matches every aspect of the input specification.
However, as hinted previously, the quality control process for finished goods involves defining standards and inspecting raw materials. A rigorous process with quality control measures and monitoring ensures that the manufacturing of any goods retains quality from start to finish.
Through this blog post, we have discussed how the quality control process ensures consistency in production lines from start to finish.
Why Quality Control Matters in Injection Moulding
Quality control is beyond checking the outcome of the manufacturing process or the final product delivery. It’s an integral part of manufacturing. Quality control is ingrained in every part of the manufacturing process.
Manufacturing companies start by defining a standardized monitoring process that allows you to leverage digital tools, and so much more.
Ensure Product consistency: Through constant quality assurance and quality checks, manufacturing lines can improve at different touchpoints. A standardized monitoring process helps track errors in production lines, stops defective parts from reaching the market, and reduces material waste.
Enhances Reliability of the Product and Performance: Quality control processes enhance the product accuracy with the plastic injection moulding process. The process involves inspecting and ensuring the accuracy of the mold, the parts, and the goods it produces.
Production Cost Reduction: Quality control measures ensure manufacturers don’t have to spend time, money, and materials to rework the production after manufacturing failure.
Preventing defects through constant inspection and error detection results in cost reduction at the early production level. In addition, the produced goods become failsafe, and fewer warranty claims are paid for as a result.
Ensuring Compliance: Product safety and performance are essential to maintaining compliance and production standards that the government enforces. Quality control in different phases of the production line ensures compliance.
Enhance Customer Satisfaction and Trust: Dependable products and efficiency in customer service build trust, and the process of trust building starts at the manufacturing line with constant quality inspection of the product.
Key Stages of Quality Control in Injection Moulding
Advanced manufacturing companies with strict quality assurance protocols maintain the following stages to ensure product quality through the injection molding process.
1. Material Selection and Handling
Material selection and handling are the foundation of the injection molding process. Manufacturers must choose the right raw material (plastic resins in this matter), adhering to the desired product quality. It’s typically a critical part of quality control as well, and the selection material ensures the:
- Cost
- Durability in different environmental conditions
- Manufacturability of the product
The key consideration for quality control for raw material selection includes selecting quality parameters. Common quality parameters are:
- mechanical (strength, flexibility)
- thermal (heat resistance)
- and chemical properties.
The plastic injection molding process relies on well-handled and preserved raw materials. The material is initially kept in powder or pellet form. Handling and preserving the raw materials carefully ensures that there are no defects in the final molded part.
The quality control in this stage involves two things:
| Material Properties | Proper Storage |
| Engineers must understand the thermal stability, moisture content, and viscosity of the material, additives, and colorants for the resins. | Materials must be stored in clean, moisture-free environments. The preservation process here ensures quality by preventing contamination and degradation of the product. |
2. Mold Design and Maintenance
The quality of the final product and the precision according to the specifications and instructions depend on the mold. The mold is the heart of the injection molding process. Inefficiency in mold design can lead to product defects and manufacturing errors.
The manufacturers can lose work hours, waste effort, and resources in building inefficient products unless the mold has a precise design.
As part of quality control in manufacturing, it’s integral to inspect mold design before moving into the manufacturing stage. A thorough inspection leads to optimal material flow, efficient cooling, and smooth part ejection for the final product.
Quality control at this level ensures two things:
| Design for Quality | Maintenance |
| Uniform wall thickness, venting and proper gating helps avoid common defects such as sink marks, warping, and incomplete filling. | Regular checks ensure that the molds are free from any wear, tear, cracks, or damage. This helps them maintain a consistent quality of the parts being manufactured. |
3. Machine Calibration and Process Optimization
Machine calibration and process control are critical factors in the plastic injection method for manufacturing. In fact, it ensures efficient product quality and precise calibration, also ensuring that the machines are operating under a specific tolerance level. Maintaining calibration and optimizing the process is essential to achieving the integrity of the model parts.
Calibrating Equipment: Injection machines must go through inspection phases to ensure precise control of pressure, shot size, and temperature during manufacturing.
Parameter Control: Close monitoring of the melt temperature, injection pressure, speed, and cooling ensures consistency in the production line without any disruption.
Scientific Moulding: Advanced methods, such as Design of Experiments (DOE), optimize settings scientifically for repeatable results.
4. In-Process and Post-Production Inspection
As hinted before, inspection isn’t the last phase. It’s a process that takes place throughout the manufacturing process in plastic molding. In-process quality control measures involve the following stages:
- First Article Inspection (FAI): Early inspection of initial parts helps verify the quality and the correctness before mass production of any material. Think of it like A/B testing before going into full production.
- In-Process Monitoring: Sensors, cameras, and real-time checks during the manufacturing processes identify defects as they occur. This way, defects and errors get eliminated in the manufacturing stage itself. Thus, it’s easier to minimize large-scale rework after mass manufacturing of defective products.
- Post-Production Testing: Final products undergo dimensional measurement, functional validation, and visual checks before shipment.
5. Quality Management Systems
While technical checks and monitoring manufacturing at different phases of manufacturing help, it’s essential to ensure consistency across operations. Manufacturers nowadays are taking help from advanced quality management systems.
Statistical Process Control (SPC): This is a method that uses data and analytics to detect different patterns and deviations in the production line.
Total Quality Management (TQM): This process of the quality management system simplifies quality parameters into easily manageable components of production.
Advanced Automation: Tools like Computer-Aided Quality (CAQ) and Totally Integrated Automation (TIA) allow continuous, automated monitoring of dimensions and tolerances.
Lead Manufacturing Industry with Quality!
From handling the raw material for production to well-designing the entire product by managing mold design and post-delivery inspection, quality control is inevitable. The manufacturing industry depends on efficient quality control by default.
It requires a combination of technical precision and management systems such as SPC and TQM. Only through efficient quality control can manufacturers achieve consistent quality output in every repetition of the process.
