How to Ensure Quality Control for Your Injection Molded Parts?

If you’re developing injection molded parts, you know that quality control is vital. That’s why it’s important to create a detailed plan to help guarantee that your parts meet all the necessary requirements, including design and manufacturing. Here’s what you need to know about developing a quality control plan for injection molded parts.

Importance of quality control

Quality control is undoubtedly significant when it comes to injection molding, as even the slightest mistake can ruin the entire production process. You also paid a hefty injection molding machine price. That’s why it’s so important and difficult to ensure that products are perfectly constructed so that no re-dos or repairs will be needed and everyone ends up happy with their purchase. With the help of precision measurement tools and top-quality materials, a process like injection molding can guarantee that customers receive only the very best in terms of product quality. Quality control also provides assurance to customers that the item they’re getting won’t malfunction shortly after its use begins. So if you have a business dealing in injection molded products, don’t skimp on your quality control. It’s worth making sure each product manufactured meets your standards every single time.

Step-by-Step Process of Quality Control

Step 1: Analyze Design Requirements

The first step in creating a quality control plan is analyzing all of the design requirements and specifications. This includes everything from material selection, wall thickness, and draft angles to surface finish and part tolerances. It’s essential that these parameters are all established ahead of time so that there are no surprises later on down the line.

Step 2: Establish Quality Standards

Once you have analyzed the design requirements, it’s time to establish specific quality standards for each one. This means setting measurable goals for each parameter with clear pass/fail criteria, as well as establishing acceptable levels of variance between measurements taken at different points along the production process.

Step 3: Develop Testing Processes

The third step in creating a quality control plan is developing testing processes to ensure that your injection molded parts meet the established standards. Depending on how complex your parts are and what kind of materials they are made from, this might include things like strength tests, environmental tests, dimensional analyses, or chemical analyses. It’s also essential to ensure that any test methods are used to meet industry standards.

Common Defects and Problem Areas

Common defects and problem areas in injection molding can include shrinkage, air traps, imprints left by tools on the plastic, sink marks caused when parts cool unevenly, gas marks due to outgassing from trapped gases inside the plastic, and design issue flaws from lack of consideration for shrinkage or filling. It pays to consider these plastic pitfalls as you go through your injection molding process to ensure you get the best possible result every time.


Creating a quality control plan for your injection molded parts is essential to ensuring successful production runs and customer satisfaction. By analyzing design requirements, establishing measurable quality standards, and devising appropriate testing processes, you can be sure that your parts meet all necessary specifications—and exceed customer expectations.