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718H Pre-Hardened Steel Square Mold Cavity Insert With Side Slide Structure
This integrated square mold cavity block is 5-axis CNC & sink EDM machined for precision plastic injection molds, equipped with central square forming cavity with rounded transition forming bosses, four-corner mold mounting through holes and built-in side slide limiting mechanism. It serves as independent interchangeable forming insert for small multi-cavity injection molds.
- Material: 718H Pre-Hardened Mold Steel
Hardness: HRC 28–32
Tolerance: ±0.002 mm
Surface Finish: Fine Matte Milled Outer Surface
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Integrated Cavity & Side Slide Engineering
One-piece square block combines forming cavity and side core-pulling slide base into a single unit, simplifying mold assembly and reducing mold stacking tolerance accumulation. Central square cavity with seamless rounded inner transitions eliminates plastic flow marks, weld lines and sharp edge burrs on molded plastic products. Embedded side slide limit groove with removable wear-resistant slide stop block accurately controls side core pulling stroke, effectively preventing over-travel collision damage to mold inserts. Four symmetrical corner mounting holes provide uniform clamping force during mold closing, maintaining stable cavity positioning precision after millions of mold opening/closing cycles. Thick solid monolithic square body delivers strong anti-deformation rigidity, resisting bending under high injection pressure to avoid product dimensional deviation and flash defects.
Balanced Toughness 718H Pre-Hardened Mold Steel Construction
718H pre-hardened steel brings comprehensive advantages for small interchangeable mold cavity inserts:
- Delivered pre-hardened, eliminating secondary heat treatment and shortening mold lead time
- Balanced hardness and impact fatigue toughness, resistant to surface indentation and cracking under long-term repeated mold clamping impact
- Excellent polishing performance to achieve mirror-grade inner cavity surface, directly producing high-gloss plastic parts without secondary post-processing
- Stable thermal conductivity balances mold temperature across the whole cavity surface, reducing local hot spot shrinkage defects
- Supports secondary texture etching, gas nitriding and PVD hard coating to extend mold service life Ideal for medium-volume mass production of small electronic components, cosmetic accessories and miniature household plastic parts.
Custom Mold Cavity Insert Support
- Custom inner cavity contour, slide stroke length, block overall dimension and mounting hole layout based on customer plastic product 2D/3D CAD drawings
- Optional surface upgrades: Mirror Polishing, Chemical Texture Etching, Gas Nitriding Anti-Wear Treatment, Anti-Corrosion Passivation
- DFM mold flow simulation consultation: cooling circuit matching, plastic shrinkage compensation, side slide force balance optimization
- Fast single-piece prototype cavity sampling and mass batch interchangeable mold insert delivery
Key Features & Advantages
- Combined Cavity & Slide Integrated Design: Integrates forming cavity and side core pulling base to simplify mold structure and assembly steps.
- Seamless Rounded Inner Cavity Transitions: Eliminates plastic dead flow zones to improve molded part surface quality.
- Removable Wear-Resistant Slide Stop Block: Easy disassembly for replacement, lowering mold maintenance cost.
- Pre-Hardened Steel Ready-To-Use: No post heat treatment required, greatly shortening mold manufacturing cycle.
- Fully Customizable Cavity Geometry: Adjust square cavity size, boss profile and slide groove dimension to match miniature plastic molding demands.
Technical Specifications
| Parameter | Specification |
|---|---|
| Base Material | 718H Pre-Hardened Mold Steel |
| Alternative Materials | S136 Stainless Mold Steel, NAK80 Mirror Mold Steel, P20 Mold Steel |
| Hardness | HRC 28–32 (As-delivered pre-hardened) |
| Dimensional Tolerance | ±0.002mm for cavity contour, hole position & block flatness |
| Flatness | ≤0.003mm per 100mm block length |
| Surface Roughness | Ra ≤0.02μm polished inner cavity; Outer surface Ra ≤1.6μm milled matte |
| Manufacturing Processes | 5-Axis CNC Milling, Sink EDM, Precision Drilling, Mirror Polishing, Deburring |
| Surface Treatments | Mirror Polishing, Texture Etching, Gas Nitriding, PVD Hard Coating |
| Customization | 100% Fully Customized via CAD Drawings & Plastic Product Samples |
Applications
Miniature Consumer Electronic Multi-Cavity Molds
Square cavity inserts for earphone parts, connector shells and small battery plastic covers. Integrated side slide structure solves small undercut demolding problems for high-speed mass production molds.
Cosmetic Small Accessory Molding Tools
Precision mold inserts for lipstick inner cores, cosmetic bottle small buckle components. Mirror polished cavity produces flawless glossy cosmetic packaging surfaces.
Medical Disposable Mini Plastic Molds
S136 stainless steel alternative inserts meet medical hygiene standards, applied to medical tube joints and miniature plastic valve molds, resisting corrosion from medical plastic additives and mold cleaning agents.
Small Automotive Plastic Fastener Molds
Interchangeable cavity blocks for automotive plastic clips and wiring buckles, rigid square body maintains stable dimensional precision under continuous high injection pressure.
Precision Stamping Auxiliary Forming Dies
Mini square forming inserts for thin plastic film stamping and shaping equipment, wear-resistant steel surface extends service life under long-cycle forming operation.
