Ledwell Expands Quality Control | Meet Paige

May 5, 2023


Quality Control in the Field of Injection Moulding: An In-Depth Guide

**Paige Otter, Ledwell’s Quality Control Supervisor

Injection moulding, a cornerstone manufacturing process, has been the backbone of the plastic industry for decades. It’s a complex procedure that requires precision, expertise, and strict quality control measures. This post delves into the quality control aspect of injection moulding, highlighting its importance, the procedures involved, and the benefits it offers.

The Art of Injection Moulding

Before diving into quality control, let’s understand the process of injection moulding. It’s a technique where molten plastic or composites are forced into a mould to create a part, a product or component. There is a wide range of different plastics to choose from as well as composites and biodegradable materials. The process begins with the material being heated until it becomes molten. It’s then injected into a mould under pressure, cooled to solidify, and eventually removed from the mould. The result is a solid part fashioned and engineered from your chosen material.

Injection moulding technology came into existence in the early 1870s, initially used to manufacture billiard balls. Fast forward to today, and injection moulding has become a versatile method to create a plethora of products – from drink tumblers and automotive parts to musical instruments and medical devices.

The Vital Role of Quality Control in Injection Moulding

In the world of injection moulding, quality control is crucial. It’s a systematic process that ensures the final products meet the set specifications and consumer expectations. Several factors, including dimensional stability, colour, gloss, and moulding defects, define how well the product aligns with the intended design and overall quality.

Quality control is not just a term used to boost brand image or a buzzword thrown around casually. It’s a rigorous process that involves meticulous planning, design, development, assembly, production, and packaging. Quality control measures are integral to the success of a business, reducing production costs and boosting customer satisfaction.

Dimensional Stability and Quality

Dimensional stability is an important aspect of quality control. If the product is an individual piece that doesn’t connect to anything, the dimensions might not matter. However, for components that fit together to form an assembled product, having the correct dimensions is crucial.

Each component must conform to specific dimensions to fit with other parts correctly. This includes being neither too large nor too small and maintaining the right shape to fit, perfectly with other components. If the components don’t fit together, the entire assembly might not function as intended, resulting in halted manufacturing lines or dissatisfied customers.

The Impact of Colour in Injection Moulding Quality Control

Colour is another critical factor that can affect the overall quality of the product. Changing process parameters, such as increasing or decreasing temperature and pressure, can affect the end colour of the product. There are different ways to colour the plastic, including pre-coloured plastic from a plastics manufacturer or a blended plastic created at the moulding factory.

Colour harmony is crucial to ensure each component meets the specification, meaning each part aligns with the intended colour within a few shades. It’s important to show uniformity and consistency of colour between all components, meeting the design intent.

The Role of Gloss in Product Quality

Gloss, though a small detail, can significantly influence the perceived quality of the product. The right gloss level can enhance your product’s visual appeal, influencing your consumer’s perception. The process parameters during moulding can influence gloss to a certain degree. For instance, high temperature may increase gloss, while the time in the mould could decrease the gloss level of your product.

Common Moulding Defects and Quality Control

Moulding defects can affect the quality of your product. The five most common defects that may occur include flow/weld lines, sink marks, short shots, burn marks, and flashing. Each of these defects can compromise the overall quality of the product, deterring customers from purchasing it.

However, not all defects warrant discarding the product. For instance, some defects might be acceptable on an internal component that isn’t visible after assembly. The product specification should outline if a defect is acceptable, its acceptable location, and the degree of defectiveness allowed.

Benefits of Quality Control in Injection Moulding

Quality control in injection moulding comes with numerous benefits. It encourages a quality-conscious approach among the workers, leading to higher product quality. It also reduces production costs by minimising waste and inefficiencies. Companies can ensure the utilisation of resources, improve employee morale, and satisfy customers by maintaining stringent quality control measures. Additionally, quality control helps identify and fix problems early, reducing returns and failures.

Quality Control Trends: AI and Advanced Quality Assurance Tools

Quality control in injection moulding has seen significant advancements with the emergence of artificial intelligence (AI) and advanced quality assurance tools. AI enables complex and reliable quality control systems, ensuring consistency in mass production. The integration of AI with quality control systems allows automatic adjustments to the moulding cycle, improving the overall production process.

In addition to AI, advanced quality assurance tools like IdentiPol QA2 have revolutionised quality control in injection moulding. It enables efficient quality assurance tests, ensuring consistency and quality across the production line. It’s a user-friendly tool that grades plastics based on a pass or fail basis, bridging the gap between simple testing and complex lab analysis.

To find out more about Ledwell’s quality control procedures please contact Paige Otter paige.otter@ledwellplastics.com Ledwell’s quality control supervisor.

Ledwell Plastics excels at injection mould design, toolmaking, plastics injection moulding, assembly, and just in time production.  We offer a turnkey solution that can organise a new product launch from concept to consumer.  We have a complete turn-key solution to bring your product to market, and we are ISO9001:2015 certified

Summary
Photo ofPaige Otter
Name
Paige Otter
Website
Job Title
Quality Control Supervisor
Company
Ledwell Plastics
Address
Ledwell Plastics Ltd. 33 Cannock St,
Leicester, Leicestershire, LE4 9HR