Insert molding integrates metallic components directly into thermoplastic or thermoset resins during the injection cycle. This process eliminates post-molding assembly steps, improves mechanical retention through structural undercuts, and reduces overall component weight. Built to customer CAD specifications for high-reliability automotive, medical, and industrial electronics applications under strict IATF 16949 quality management.
Technical Specifications
Clamping Force Range:
50T to 500T vertical and horizontal presses.
Shot Weight Capacity:
2g to 1,500g.
Dimensional Tolerance:
Standard ISO 20415 (Fine tolerance up to ±0.02 mm achievable depending on geometry).
Insert Material Compatibility:
Brass, stainless steel (303/304/316), carbon steel, phosphor bronze, and aluminum.
Resin Compatibility:
PA6, PA66 (GF reinforced), PBT, PC, ABS, POM, PPS, PEEK, and TPU.
Quality & Compliance:
IATF 16949, ISO 9001 certified manufacturing; RoHS and REACH compliant material supply chain.
Key Features
Mechanical Interlock: Knurled, grooved, or slotted insert geometries prevent rotational slip and axial pull-out under load.
Zero Secondary Fasteners: Consolidates multi-part assemblies (screws, nuts, washers) into a single molded unit.
Hermetic & Moisture Sealing: Molten polymer flows tightly around micro-features, preventing fluid or gas leakage along the insert interface.
High Strength-to-Weight Ratio: Replaces heavier metal housings with engineered plastics while retaining metallic thread strength.
Materials & Options
High-Performance Engineering Resins:
PPS / PEEK:
Continuous use temperatures above 200°C, chemical resistance for under-hood automotive.
PA66-GF30:
High tensile strength and rigidity for structural brackets.
PBT-GF30:
Excellent dimensional stability and electrical insulation for connectors.
Insert Surface Treatments:
Passivation, nickel plating, zinc plating, gold flash (for electrical contacts), and clean-pass ultrasonic degreasing.
Manufacturing Process & DFM Checklist
• DFM & Mold Flow Analysis: Evaluate gate location, weld lines, and stress concentration around metal inserts before tooling fabrication. To prevent insert displacement or thin-wall deformation under high injection pressure, custom magnetic and mechanical locators are engineered for each insert geometry.
• Insert Loading: Manual or automated robotic pick-and-place positioning into precision mold cavities.
• Molding Cycle: Clamping, precise melt temperature control, controlled injection velocity, and cooling.
• De-molding & Inspection: Automated part ejection followed by strict visual and dimensional verification.
Core DFM Review Parameters for Engineering Teams:
• Wall Thickness & Resin Flow: Ensuring uniform wall thickness around inserts to prevent sink marks, warping, and uneven thermal stress.
• Insert Undercuts & Knurling: Verifying that knurl patterns or grooves provide sufficient surface area for mechanical locking without causing high stress concentrations in the plastic.
• Gate Placement: Positioning injection gates away from critical insert interfaces to avoid weld line weaknesses or insert displacement during high-velocity filling.
• Minimum Plastic Cover: Ensuring adequate surrounding wall thickness around metal inserts to withstand hoop stress and thermal expansion differences.
Quality Control & Testing Standards
In-Process Monitoring:
Closed-loop injection molding machines tracking cavity pressure, melt temperature, and cycle consistency in real time.
Mechanical Testing:
Push-out and torque-out destructive testing conducted per lot on automated test fixtures to verify insert retention strength against engineering standards.
Dimensional Verification:
3D CMM (Coordinate Measuring Machine) inspection, optical comparators, and pin gauges for critical-to-function (CTF) dimensions.
Traceability & Documentation:
Raw material lot certification (CoA), full production run data logs, and PPAP (Level 1 to Level 3) packages available upon request. Records maintained for 5 years.
Customization & Commercial Terms
Tooling Ownership: Exportable, customer-owned production tooling (H13, S7 steel) with guaranteed life-cycle maintenance.
Production Models: Flexible scaling from pilot runs to high-volume multi-cavity programs. Rotary table vertical presses available for high-throughput over-molding.
Minimum Order Quantity (MOQ): Scaled to project phase (prototypes from 500 pcs; production volumes evaluated per program).
Packaging Customization: ESD-safe trays, custom thermoformed blisters, or bulk packaging aligned with automated assembly lines.
Applications
ECU housings, sensor brackets, wiring harness connectors, and fuel system valves.
Terminal blocks, circuit breaker components, heavy-duty connector shells, and switch housings.
Diagnostic equipment manifolds, surgical tool handles, and fluid delivery connectors.
Packaging & Delivery
Packaging Standards: Anti-static bagging, corrugated cartons with customized dividers to prevent transit abrasion, and ISPM 15 heat-treated wooden pallets.
Logistics Support: Scheduled blanket orders, Kanban delivery models, air/ocean freight coordination, and complete customs export documentation.
FAQ
Q: How do you prevent insert displacement during high-pressure injection?
A: We utilize custom-machined locating pins within the mold, magnetic retention where applicable, and optimized injection velocity profiles to balance cavity pressure evenly around the insert.
Q: What is the typical tooling lead time and sample approval process?
A: Standard tooling fabrication and T1 sampling require 4 to 6 weeks. T1 samples are shipped alongside full CMM dimensional reports and material test sheets for client sign-off.
Q: Do you support PPAP documentation for automotive projects?
A: Yes. As an IATF 16949 certified facility, we routinely deliver full PPAP packages (Level 1 through Level 3) including FMEA, process flow diagrams, and dimensional results.
Request A Quote & Recommended RFQ Email Template
To receive a technical review, DFM feedback, and commercial quotation within 24 hours, submit your package containing:
1.3D CAD models (STEP or IGES format).
2.2D engineering drawings with tolerance callouts and CTF dimensions.
3.Estimated annual volume and target batch sizes.
4.Material specifications and operational environment requirements.
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