Hitachi HPM38 Plastic Mold Thread Core & Gear Inserts

Corrosion-Resistant Precision Components for Injection Molds

Product Overview

Our Hitachi HPM38 thread cores and gear mold inserts are precision components used in plastic injection molds requiring high surface quality, corrosion resistance, and dimensional stability.

These inserts are typically used to form:

• Plastic gears

• Threaded plastic components

• Cosmetic rotational parts

• Medical screw-type parts

• Precision drive components

Manufactured from HPM38 stainless mold steel, these components offer excellent polishing properties and stable performance in high-cycle production environments.

All parts are produced strictly according to customer drawings (Built-to-Print).

Material – Hitachi HPM38

HPM38 is a pre-hardened stainless mold steel known for:

• Excellent corrosion resistance

• Superior polishability (mirror finish capable)

• Stable hardness

• Good wear resistance

Compared with standard tool steels, HPM38 is especially suitable for:

• Transparent plastic molds

• Cosmetic packaging molds

• Medical device molds

• High-humidity production environments

Typical hardness:
Pre-hardened condition suitable for precision mold inserts (custom heat treatment available).

Typical Applications

These thread cores and gear inserts are widely used in:

• Cosmetic cap molds

• Rotating cosmetic components

• Plastic gear molds

• Medical syringe components

• Electronic mechanical parts

• Small transmission plastic gears

Especially suitable for molds requiring both precise tooth geometry and high surface finish.

Engineering Focus

Thread and gear inserts directly affect:

• Engagement accuracy

• Torque transmission

• Noise level in gear systems

• Demolding smoothness

• Product appearance quality

Key technical priorities include:

1) Tooth & Thread Geometry Precision

• Controlled pitch and module accuracy

• Accurate flank angles

• Tight concentricity control

• Tolerance capability up to ±0.005 mm

Precision machining ensures proper meshing performance and stable torque output.

2) Surface Finish Quality

HPM38 allows:

• Fine polishing

• Mirror finishing

• Reduced friction during demolding

• Improved cosmetic surface quality

Surface finish can be customized according to application.

3) Corrosion Resistance

In cosmetic and medical production:

• Moisture and chemical exposure are common

• HPM38 resists rust and staining

• Reduces maintenance frequency

This improves mold longevity and reduces downtime.

Manufacturing Capability

Processing includes:

• CNC turning

• CNC milling

• EDM for detailed profiles

• OD grinding

• Precision finishing

• CMM inspection

All critical dimensions are verified before shipment.

Supported drawing formats:

PDF, DWG, DXF, IGS, STEP, etc.

Quality Control

Inspection equipment includes:

• Hardness tester

• CMM (Coordinate Measuring Machine)

• Height gauge

• Projector

• Calipers

Each part undergoes 100% inspection before delivery.

OEM / Custom Manufacturing

We support:

• Manufacturing from 2D / 3D drawings

• Custom thread or gear standards

• Small batch orders

• Replacement mold inserts

• Rapid sample production

MOQ: 1 piece
Production capacity: approx. 2000 pcs/week (depending on size)

Related Products

To complete injection mold assemblies, we also supply:

• Precision thread cores (H13 / SKH51)

• Plastic mold cavity inserts

• Gear core inserts

• Multi-cavity cap mold components

• Ejector pins and sleeves

• Stainless mold core plates

All components are manufactured for compatibility within injection mold systems.

Technical FAQ

Q1: Why choose HPM38 for thread or gear inserts?
HPM38 offers excellent corrosion resistance and polishing capability, ideal for cosmetic and medical applications.

Q2: Can precision gear tooth profiles be customized?
Yes. All gear modules and thread profiles are manufactured according to customer drawings.

Q3: Is mirror polishing available?
Yes. HPM38 supports high-gloss and mirror finishes.

Q4: Are small quantity orders accepted?
Yes. MOQ starts from 1 piece.

Request a Technical Quotation

To receive a quotation, please provide:

• 2D / 3D drawings

• Material requirement

• Surface finish specification

• Production volume

• Delivery timeline

Our engineering team will review your specifications and provide a detailed manufacturing proposal.