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Integrated Motor Stator Core Overmolding & Polymer Encapsulation

Direct high-adhesion polymer encapsulation molded onto customer-supplied or in-house sourced laminated silicon-steel stator cores. Engineered with DuPont/BASF modified PPS, PA46, and PA66+GF to replace multi-piece assembled bobbins—eliminating air gaps, preventing thermal delamination, and improving heat dissipation.

✓ Delamination-Free Metal-Plastic Bonding

✓ Zero Flash on Stator Bore & Teeth

✓ 100% High-Pot & Coaxiality Verified

RUNHENG motor component product reference on a white background.
RUNHENG motor component product reference on a white background.
RUNHENG motor component product reference on a white background.

PRECISION TOLERANCE

±0.02mm Coaxiality

CORE POLYMERS

PPS, PA46, PA66+GF, LCP

SAFETY & COMPLIANCE

UL94 V-0 · CTI ≥ 600V · RoHS/REACH

TOOLING & LEAD TIME

15–25 Days T1 · 7–10 Days Insert Swap

WHY ENGINEERS CHOOSE RUNHENG STATOR OVERMOLDING

Zero Delamination, Zero Core Crush & Higher Winding Slot Fill

01. Thermal-Matched Anti-Cracking Bonding

Controlled pre-heating of silicon-steel stator stacks paired with low-shrinkage modified PPS/PA66+GF prevents weld-line cracking or plastic-to-metal delamination across -40°C to 220°C+ thermal shocks.

02. Zero-Flash Precision Shutoffs

Micron-level Charmilles Wire EDM mold shutoffs seal tightly against stator lamination stack tolerances, keeping the inner rotor bore and outer mating diameter 100% free of plastic flash.

03. Higher Slot Fill & Better Heat Transfer

Direct thin-wall slot encapsulation (down to 0.12mm–0.3mm) eliminates the air gap between plastic and steel, lowering thermal resistance and increasing copper winding space.

04. Vertical Insert Molding Automation

Dedicated vertical rotary-table injection presses protect delicate silicon-steel laminations from clamping deformation while maintaining ±0.02mm coaxiality.

TECHNICAL SPECIFICATIONS

Stator Core Overmolding Engineering Parameters

Request PDF Spec Sheet →

Available Overmolding Resins

High-Flow Modified PPS, PA46, PA66+GF (15%–35%), LCP, PBT+GF (DuPont / BASF Partners)

Flame Retardancy & Tracking

UL94 V-0 Certified; CTI ≥ 600V High-Voltage Tracking Resistance

Minimum Slot Wall Thickness

Down to 0.12mm–0.35mm Uniform Slot Insulation (±0.02mm Tolerance)

Thermal Endurance

180°C to 220°C+ Continuous Operating Temperature

Metal Core Supply Mode

Overmolding on Customer-Supplied Unwound Cores OR Turnkey Core + Overmolding

Mold Clamping Protection

Spring-Loaded Stack Height Compensation & Precision Center-Bore Arbors

Quality & Defect Control

≤ 50 PPM; 100% Inner-Bore Go/No-Go Gauging & High-Pot Breakdown Testing

Certifications

ISO 9001:2015, ISO 14001:2015, UL Process Certified, RoHS & REACH

STANDARD & CUSTOM CONFIGURATIONS

Supported Stator Overmolding Configurations

Slot-and-End-Cap Unwound Stator Overmolding

Direct insulating coating inside winding slots and on both stack ends, replacing separate top/bottom bobbins and slot paper.

Inquire Unwound Stators →
RUNHENG motor component product reference on a white background.

Outer-Rotor BLDC Stator Encapsulation

Overmolded multi-slot outer-rotor cores with integrated central bearing boss and mounting flange.

Request Custom Quote →
RUNHENG motor component product reference on a white background.

Full Waterproof Stator Encapsulation

Complete polymer overmolding over stator assemblies for submersible pumps, marine thrusters, and outdoor actuators.

Discuss Waterproof Molding →

HOW WE GUARANTEE CONSISTENCY

How We Guarantee Zero Lamination Damage & Tight Bonding

01. Stator Stack Cleaning & Pre-Heating

Incoming silicon-steel cores are inspected for stack height tolerance, cleaned of stamping oil, and pre-heated to prevent premature melt freeze-off.

02. Balanced Multi-Gate Vertical Injection

Symmetric pin-point gating ensures even melt pressure around every stator tooth without bending thin laminations.

03. 100% Bore Plug-Gauge & High-Pot QC

Every overmolded stator undergoes inner-bore concentricity gauging and 1.5kV–3kV AC dielectric withstand voltage verification.

03 / INSERT MOLDING & STATOR OVERMOLDING FAMILY

Explore Other Metal-Insert Overmolded Components

← Back to All 4 Product Families

FAMILY 03 · SIBLING COMPONENT

3.2 Overmolded Lead Screws & Shafts

Wear-resistant, self-lubricating engineering plastics molded directly onto stainless steel lead screws, motor rotor shafts, or brass guide cores.

Explore Overmolded Lead Screws →

FAMILY 03 · SIBLING COMPONENT

3.3 Splined Brass Bushings & Linear Limiters

High-strength metal-plastic composite components combining splined brass or steel bushings with lightweight, vibration-damping engineering plastics.

Explore Bushings & Limiters →

FAMILY 03 · SIBLING COMPONENT

3.4 Hollow Shafts with Molded Internal Threads

Precision internal threads and splines formed directly inside the injection mold for hollow-core motor shafts.

Explore Hollow Threaded Shafts →

DIRECT ENGINEERING SUPPORT

Have a Stator Core Drawing for Overmolding Evaluation?

Upload or email your 2D/3D component drawing (STEP, IGES, DWG, PDF) or share your component geometry. Free standard stock samples are available (freight collect), and custom DFM reviews are returned within 24 business hours.

✓ Free Standard Stock Samples (Freight Collect)
✓ 24-Hour Engineering DFM & Quote Response
✓ 100% NDA Confidentiality Protection

Send Your 2D/3D Drawing or Sample Request

Fill out the project specs below or attach your CAD files. Our engineering team responds within 24 business hours.

📎 Drag & drop your 2D/3D drawing here, or click to browse (.step, .stp, .iges, .igs, .x_t, .dwg, .dxf, .pdf, .zip — Max 25MB)No file selected

🔒 100% Confidential. NDA available upon request.

💬 Or WhatsApp Us: +852 9099 5624