Screw Plugs for Holding Core Pin Fine Threads

These fine-thread screw plugs are used inside injection mold assemblies to retain and stabilize core pins during repeated molding cycles. The MSWPN-style fine threads provide controlled engagement, helping maintain consistent positioning under clamp load and preventing gradual loosening.

• Automotive connector and insert molds: Use the plugs to hold slender core pins that form small internal features. The fine pitch supports a secure, stable fit when the mold experiences high cycle counts.
• Electronics housings and small-part plastics: Install in core-support areas where dimensional accuracy matters. The plug’s short, defined lengths (L) help achieve repeatable thread takeover without bottoming into critical components.
• General multi-cavity plastic mold tooling: In locations requiring tight core pin retention, fine threads improve assembly integrity and reduce the risk of core pin drift.

The available nominal diameter set (M=12–30) and length options (15–25 mm) allow engineers to match retention needs to specific core-pin designs while preserving reliable thread engagement.

The provided product data specifies dimensions (M nominal diameter and length L) but does not include a steel grade, heat treatment state, or hardness value. Therefore, material properties such as HRC hardness, wear resistance, and toughness trade-offs cannot be stated from the supplied information.

When selecting a screw plug for core-pin retention, engineers typically choose a tool steel or nitriding-capable steel to balance thread wear resistance with adequate toughness against chipping under assembly and operational loads. If your application requires higher thread surface wear resistance (e.g., frequent maintenance access), confirm whether the available variants are made from a pre-hardened, quenched-and-tempered, or surface-treated (such as nitrided) steel.

• Material verification required: Request the exact steel grade and heat treatment for the selected M (12, 16, 20, 24, 30) and L (15, 20, 25) configuration.
• Typical selection logic: Higher hardness generally increases wear resistance but can reduce impact toughness at the same geometry if not properly tempered.

Select the screw plug based on two parameters: M (nominal thread diameter) and L (length, mm). Available nominal diameters are M = 12, 16, 20, 24, 30, and available lengths are L = 15, 20, 25 mm.

• Match core-pin retention requirements: Choose the M that corresponds to the thread size designed for the core pin retention pocket. Using the correct nominal diameter is essential to ensure thread engagement and stable clamp-related retention.
• Control engagement depth: Select L so the plug provides adequate thread takeover without excessive protrusion or bottoming in the receiving bore.
• Tolerance/fit considerations: Because fine threads are sensitive to assembly tolerances, confirm that your mold component’s thread pitch/lead and depth match the plug’s fine-thread design. If your design uses tight positional interfaces around the core pin, verify installed stack-up to avoid reducing effective engagement.

Configurable dimensions in this series are limited to M (12–30) and L (15–25). All other functional fit characteristics should be confirmed against the mold’s thread specification before machining final core-pin pockets.