Rubber performance testing molds, rubber sample preparation molds, rubber inspection dedicated molds, Hooren mold

2025-10-09 11:57:24 Rubber testing molds

Special molds for rubber testing are core to accurate rubber performance testing. Dumbbell-shaped, ring-shaped, and flat-plate molds (key components) support sample preparation/testing for different forms. Together with rubber performance testing, sample preparation, and special testing molds, they form a "preparation-testing-verification" chain, directly ensuring sample consistency and data reliability.

I. Core Material Technology

1. Mold Base Materials

Common Requirements: Thermal resistance ≥ 300℃, hardness ≥ HRC 50, wear resistance ≥ 500 HV, corrosion resistance to vulcanizing/release agents.
Differentiated Selection:

Alloy Tool Steel (Cr12MoV): For dumbbell-shaped molds (precision 0.005–0.02 mm, ensures uniform sample stress areas).
Aluminum Alloy (6061-T6): For flat-plate molds (thermal conductivity ≥ 150 W/(m·K), uniform vulcanization temperature).
High-Density Graphite: For ring-shaped molds (heat resistance up to 600℃, no rubber adhesion).

2. Elastic Contact Materials

Requirements: No adhesion to rubber, deformation rate ≤ 3% after reuse.
Applications:

Silicone Rubber (60±5 Shore A): Flat-plate mold release layer (140–180℃ vulcanization resistance, easy peeling).
Polyurethane Elastomer (tensile strength ≥ 20 MPa): Ring-shaped mold sealing layer (3x wear resistance of natural rubber).

II. Mold Design & Manufacturing

1. Core Mold Classification & Structure

Mold Category	Subtype	Key Parameters	Testing Scenarios	Standard
Performance Testing	Dumbbell-shaped	Type 1: 115mm total length, 33.0±2.0mm narrow section	Tensile strength/elongation at break	GB/T 528
Special Testing	Ring-shaped	Type A: 44.6±0.2mm ID, 6.0±0.1mm width	Compressive stress/sealing performance	GB/T 528
Sample Preparation	Flat-plate	300×300×(1.0–10.0)mm, flatness ≤0.03mm/m	Shear performance/aging sample prep	GB/T 7757

2. Manufacturing Precision

Dimensional Tolerance: Dumbbell edge ±0.005mm, ring ID ±0.01mm, flat-plate thickness ±0.02mm.
Surface Quality: Performance molds Ra ≤ 0.8μm, prep molds Ra ≤ 1.6μm.
Fit Precision: Ring mold H6/k5 fit (≤0.01mm gap); flat-plate mold parting parallelism ≤0.02mm.

III. Sample Preparation Specifications

1. Preprocessing

Rubber Conditioning: Store at 23±2℃ (50±10% RH) for 2–24h; pre-roll flat-plate rubber to ±0.05mm.
Mold Cleaning: Wipe with anhydrous ethanol to remove residue.

2. Molding Parameters

Core Mold Type	Process Step	Key Parameters	Precautions
Rubber Sample Preparation Mold	Preheating of Flat-plate Mold	Temperature: 60~80℃, Holding Time: 15~20min	For flat samples with thickness > 5mm, extend holding time by 5~10min
Special Rubber Testing Mold	Vulcanization of Ring-shaped Mold	Pressure: 15~20MPa, Temperature: 150~170℃, Time: 10~15min	Adopt stepwise pressurization to avoid air bubbles in ring-shaped samples
Rubber Performance Testing Mold	Cutting of Dumbbell-shaped Mold	Cutting Speed: 5~10mm/s, Pressure: 0.5~1MPa	Check for residual rubber on the cutting edge after cutting and clean in time

3. Post-processing

Trimming: Remove dumbbell burrs (≤0.1mm); cut flat-plates to specs (e.g., 100×25mm).
Storage: Test samples within 16h–4 weeks; seal untested samples (max 3-month storage).

IV. Technology Trends

Intelligent Upgrading: Dumbbell molds with laser wear monitoring (±0.001mm); ring molds with pressure sensors (±0.1MPa).
Green Manufacturing: Recyclable aluminum flat-plate molds (≥90% recovery); biodegradable silicone; 30% energy savings via waste heat reuse.
Rapid Response: Modular dumbbell edges (5min replacement); 3D-printed ring cavities (1/3 production time).

injection mould

Technical document