Brass Moulding Insert

Product Description

A brass moulding insert is a threaded metallic component specifically engineered to be placed directly into a mould cavity before the plastic injection process begins. Unlike post-moulding inserts (which are installed after the part is cooled), moulding inserts are "moulded-in," meaning the molten plastic flows around the insert during the injection cycle. This creates the strongest possible bond between the metal fastener and the plastic part.

The Moulding-In Process

The installation of these inserts is integrated into the primary manufacturing cycle:

• Placement: The brass insert is placed onto a core pin within the injection mould tool.

• Injection: Molten thermoplastic or thermoset plastic is injected into the cavity, completely surrounding the external features of the insert.

• Encapsulation: As the plastic cools and shrinks slightly, it tightly grips the knurls and undercuts, resulting in a high-torque, high-pull-out resistant assembly that is virtually inseparable from the host material.

Key Engineering Features

• Aggressive External Knurling: Since the plastic flows while liquid, moulding inserts can feature much deeper and more complex diamond or straight knurling than post-moulding versions.

• Deep Undercuts: These grooves allow the plastic to "wrap around" the insert, providing exceptional resistance to axial loads (pull-out force).

• Blind Ends: Many moulding inserts are designed with a closed bottom to prevent molten plastic from entering the internal threads during the high-pressure injection phase.

Primary Applications

• Heavy-Duty Automotive: Used in engine covers, manifolds, and structural brackets where extreme vibration and heat are present.

• Electrical Switchgear: Providing stable, conductive-ready threads in thick-walled thermoset plastic housings.

• Aerospace Components: Integrated into carbon fiber or composite panels for high-strength fastening points.

• Industrial Pumps: Securing heavy metal plates to plastic housings in fluid-handling systems.