EN
Published by: Technical Editorial Team, Tianjin HaoRongShengYe (tjhrsy.com) / KDI Transmission
Target Audience: Global Mechanical Engineers, Chain Design Specialists, B2B Procurement Managers, and OEM Machinery Manufacturers
In power transmission and conveyor roller chains, link plates (inner and outer plates) function as the primary structural tension members. They endure continuous high-frequency cyclic tensile stresses, pitch fatigue, and severe impact loads. The manufacturing accuracy of link plates—specifically blanking/fine blanking (切板/冲裁), hole piercing, and edge conditioning—directly determines a chain's fatigue strength, pitch accuracy, and ultimate tensile capacity. This technical guide outlines the complete precision blanking process, heat treatment, and quality inspection standards for high-performance chain link plates, aligned with ISO, ANSI, and DIN specifications.
1. Raw Material Selection & Strip Preparation
Link plates require high-tensile carbon steel or alloy steel coils with strict grain orientation and thickness consistency.
Standard Steel Grades: Medium carbon structural steel like S45C / S50C, or alloy steel like 40Mn / 35CrMo for heavy-duty industrial applications.
Coil Thickness Tolerance: Strictly controlled to prevent uneven plate thickness, which causes chain twist and lateral pitch error during high-speed drive.
Fiber Direction Alignment: Stamping orientation must align with the steel rolling fiber grain direction to maximize tensile load resistance.
The "blanking" or "link plate cutting" phase creates the characteristic figure-eight geometry and critical pitch pinholes.
| Process Phase | Key Technical Requirement | Quality & Mechanical Impact |
| Progressive Die Stamping | Multi-stage automatic stamping dies at high stroke speeds | Guarantees contour symmetry and high volume dimension consistency |
| Fine Blanking (Fine Shearing) | Minimizing die clearance to achieve 80%+ smooth shear zone | Eliminates micro-tears along outer edges, boosting fatigue resistance |
| Pinhole Piercing & Ballizing | Micron-level hole pitch tolerance and surface finish | Ensures precise press-fit with pins and bushes, preventing early stretch |
Sharp burrs along stamped edges act as severe stress raisers during dynamic tension cycles and must be systematically eliminated.
Vibratory Tumbling / Deburring: Smooths outer contours and pinhole edges to eliminate microscopic notch effects.
Shot Peening : Bombarding plate surfaces with high-velocity steel shot induces compressive residual stress, increasing dynamic fatigue limit by 20% to 35%.
Heat treatment transforms soft cold-stamped plates into high-strength structural members without causing warping.
| Process Method | Operational Condition | Target Metallurgical Result |
| Continuous Quenching & Tempering | Austenitizing at 840°C–870°C followed by controlled oil quench | Tempered Martensite with high yield strength (HRC 42–48) |
| Isothermal Austempering | Quenching into molten salt bath at 300°C–380°C | Bainitic structure offering maximum toughness and zero deformation |
| Testing Parameter | Standard Target Value | Inspection Equipment |
| Plate Hardness | HRC 42 – 48 / HV 400 – 480 | Rockwell Hardness Tester |
| Pinhole Pitch Accuracy | Tolerance ±0.01 mm | Optical Comparator / CMM |
| Pinhole Roughness | Ra ≤ 0.8 μm | Profilometer / Air Gauge |
| Fatigue Resistance | Compliant with ISO 606 / ANSI B29.1 limits | High-Frequency Dynamic Fatigue Test Machine |
Video Title: How Chain Link Plates Are Stamped & Manufactured for Maximum Fatigue Life
Target Audience: B2B Procurement Teams, Industrial Transmission Engineers, Power Transmission Distributors
