THC Series brass heat set inserts are specifically designed for thermoplastic materials and feature an integrated collar (flange) that provides increased bearing surface and enhanced pull-out resistance. Installed using either thermal (heat) or ultrasonic methods, these inserts create strong, permanent metal threads in plastic components while minimizing stress on the surrounding material.
The collar design makes THC inserts particularly suitable for open-hole applications where tensile forces are applied against the flange. This larger contact area improves load distribution and significantly increases resistance to pull-out compared to standard non-collared inserts.
Thermic & Ultrasonic Installation
THC inserts can be installed after molding using either a thermic or ultrasonic insertion process, allowing manufacturers to achieve the benefits of overmolded inserts without the complexity of installing inserts during injection molding.
During installation, the surrounding plastic is softened and flows into the insert's precision-engineered knurls and grooves. Once cooled, the plastic solidifies around these features, creating a strong mechanical bond with excellent torque and pull-out performance.
THC inserts can also be installed through the overmolding process when required.
Key Benefits
- Creates strong, reusable metal threads in thermoplastic materials
- Integral collar provides increased bearing surface
- Enhanced pull-out resistance in open-hole applications
- High torque resistance
- Minimizes stress in surrounding plastic
- Suitable for post-molding installation
- Compatible with thermal and ultrasonic installation methods
- Can be installed manually or automatically
- Suitable for overmolding applications
- Excellent long-term fastening performance
Material & Finish
Material: Brass (CuZn40Pb3, CuZn39Pb3, or CuZn36Pb3)
Optional finishes available upon request:
- Tin plated
- Nickel plated
- Black zinc plated
- Other specialist finishes available for specific applications
Available Sizes
Available in a range of metric thread sizes to suit thermoplastic fastening applications.
Refer to the product size table for full dimensional and thread availability.
Applications
THC heat set inserts are widely used in:
- Plastic enclosures
- Electronic housings
- Consumer products
- Automotive plastic components
- Electrical equipment
- Telecommunications equipment
- Medical devices
- Industrial plastic assemblies
- Injection molded components
- 3D printed thermoplastic parts
Installation Process
Step 1
Position the THC insert into the molded or drilled hole using either a manual or automated installation process.
Step 2
Apply a heated insertion tool or ultrasonic sonotrode while exerting controlled pressure to guide the insert into position.
Step 3
Allow the softened plastic to flow into the insert's knurled profile and retention grooves.
Step 4
Allow the component to cool completely before handling or loading.
Installation Recommendations
For optimum performance:
- Heat should soften the plastic without fully melting it.
- Insertion pressure should be controlled and consistent.
- Allow sufficient time for plastic material to flow into the insert knurls.
- Do not disturb the insert immediately after installation.
- A cooling period of approximately 12–20 hours is recommended for many thermoplastic materials to achieve maximum retention strength.
Why Choose THC Heat Set Inserts?
THC Series inserts combine the strength of a metal thread with the holding power of a flanged design. The collar increases the contact surface between the insert and plastic component, providing superior resistance to pull-out forces in demanding applications. Suitable for both ultrasonic and thermal installation, THC inserts are an excellent choice for manufacturers seeking durable threaded fastening solutions in thermoplastics.
Product Summary
THC Brass Heat Set Inserts feature an integrated collar for improved load distribution and enhanced pull-out resistance in thermoplastic materials. Suitable for thermal, ultrasonic, and overmolding installation processes, these inserts provide strong reusable threads with excellent torque and retention performance.
