Connector Manufacturing: Insert Molding with Glow Wire Resistant Plastic
Connectors are essential components used in various electrical and electronic devices to establish a reliable and secure connection between two or more circuits. Connector manufacturing involves several steps to ensure the production of high-quality and durable connectors. One of the critical steps in connector manufacturing is insert molding of metal contacts with a glow wire resistant plastic material.
The different steps involved in connector manufacturing and the advantages of insert molding.
Step 1: Design and Engineering
The first step in connector manufacturing is the design and engineering phase. More specific, we determine the connector’s specifications, including size, shape, and electrical requirements. The connector’s design is crucial to ensure that it can withstand the intended application’s conditions and provide a secure and reliable connection.
Step 2: Tooling and Mold Making
Once we finalize the connector’s design, the next step is to create the tooling and mold required for the manufacturing process. The tooling and mold are custom-made for each connector to ensure consistent quality and accuracy.
Step 3: Insert Molding
Insert molding is a manufacturing process that involves molding a plastic material around a metal component or insert. In connector manufacturing, insert molding is used to mold a glow wire resistant plastic material around the metal contacts to provide added fire resistance. Therefore, the metal contacts are first placed into the mold, and then the glow wire resistant plastic material is injected into the mold. In this way we get a bonding between plastic and the metal contacts to form a single integrated part.
Step 4: Quality Control and Testing
After the insert molding process is complete, the connectors undergo a rigorous quality control and testing phase. Therefore, our quality controllers must ensure the cables meet the required specifications and standards. We perform various tests, including electrical testing, mechanical testing, and environmental testing. We thoroughly verify the connectors’ performance and durability.
Advantages of Insert Molding with Glow Wire Resistant Plastic
When it comes to manufacturing connectors, insert molding using glow-wire resistant plastic offers clear advantages over traditional methods. Not only does it improve safety and durability, but it also cuts costs—making it a practical solution for many applications. Let’s break down the key benefits:
1. Better Fire Safety
Unlike standard plastics, glow-wire resistant materials are specially designed to resist ignition and slow flame spread—critical in electrical fires. By molding metal contacts directly into this plastic, connectors gain an extra layer of fire protection, making them safer for high-risk environments.
2. Stronger, Longer-Lasting Parts
Insert molding bonds plastic and metal into a single, seamless unit. This eliminates weak points (like screws or adhesives) and creates connectors that hold up better against vibration, moisture, and repeated use. The result? Fewer failures and a longer product life.
3. Lower Production Costs
Since insert molding combines multiple steps into one, it slashes both labor and material expenses. There’s no need for extra fasteners or secondary assembly—just a faster, leaner process that keeps quality high while reducing waste.
The Bottom Line
At Davantech, we use insert molding with glow-wire resistant plastics because it’s a win-win: safer, tougher, and more cost-effective than older methods. By selecting the right materials and processes, we ensure every connector meets strict performance and safety standards—no compromises.
Glow Wire Testing of Insert Molded Connectors
Glow wire resistant plastic is a special material designed to prevent fires in electrical equipment. Unlike regular plastics, it can withstand extreme heat without catching fire, making it ideal for safety-critical parts like connectors, switches, and sockets. This gives manufacturers and users crucial protection against electrical fire risks.
How Glow Wire Testing Works
To ensure these materials meet safety standards, we conduct precise glow wire tests that simulate real-world electrical fires. Here’s how the testing process works:
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First, we heat a special wire to a predetermined temperature – typically between 550°C and 960°C depending on the standard being tested.
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Next, we press the glowing wire against the test sample for a set period, usually 30 seconds.
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After removing the heat source, we carefully observe whether the material ignites or continues to burn.
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Finally, we evaluate if burning droplets could potentially spread the fire.
Common Glow Wire Test Standards
Different applications require different levels of fire resistance. That’s why multiple test standards exist, each with specific requirements:
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Glow Wire Ignition Test (GWIT): Determines the minimum temperature that causes ignition
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Glow Wire Flammability Index (GWFI): Assesses whether flames self-extinguish
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Needle Flame Test: Simulates small flame exposure
The exact test parameters – including temperature, duration, and pass/fail criteria – vary depending on the product’s intended use and safety requirements. For example, medical equipment typically requires more stringent testing than household appliances.
Different glow wire tests explained in brief: 
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Glow Wire Ignition Test (GWIT):
This test measures the lowest temperature at which a material will ignite when subjected to a glowing wire. To clarify, the laboratory performs the test using a wire heated to 775°C (1427°F) and applied to the sample for 30 seconds. The GWIT temperature is the lowest temperature at which the sample ignites or sustains flaming for more than five seconds.
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Glow Wire Flammability Index Test (GWFI):
Here we measure the highest temperature at which a material will not ignite or continue to burn when using a glowing wire. More specific, the test is performed using a wire heated to 960°C (1760°F) and applied to the sample for 30 seconds. The GWFI temperature is the temperature at which the sample does not ignite or continue to burn for more than five seconds.
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Needle Flame Test (IEC 60695-11-5):
This test measures the ability of a material to resist ignition and flame spread when exposed to a small flame. In other words, the laboratory performs the test using a flame with a height of 12mm and a temperature of 650°C (1202°F) applied to the sample for 10 seconds. The criteria for pass/fail are based on the duration of flaming and the extent of damage to the sample.
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Glow Wire Tracking Test (IEC 60112):
This test measures the ability of a material to resist tracking, which is the formation of a conductive path on the surface of the material. In detail, the analyzer performs the test using a wire heated to 550°C (1022°F) and applied to the sample for a specific duration. The criteria for pass/fail are based on the formation of a conductive path and the duration of the test.
In general, higher temperatures in glow wire tests indicate greater fire resistance of the material being tested. Therefore, we carefully select the appropriate test method and temperature for connector manufacturing, based on the specific application and relevant standards and regulations.
