Engineering Bush Chains

PLW High-Strength Corrosion-Resistant Bush Chains for Industrial Machinery Use

1. Core Definition & Product Overview

2. Key Design & Material Features

2.1 Core Structural Components

• Bushings (Sleeves): Cold-drawn seamless alloy steel (40CrNiMoA) bushings with precision honed inner/outer diameters (tolerance ±0.008mm); case-hardened to HRC 58-62 for wear resistance and core toughness (HRC 30-35) to absorb impact.

• Link Plates: High-strength alloy steel (50CrVA) link plates, stamped with CNC precision dies (thickness tolerance ±0.01mm) and heat-treated (quenching + tempering) to achieve a tensile strength of ≥1200 MPa, balancing strength and fatigue resistance.

• Pins: Forged alloy steel pins (20CrMnTi) with ground surfaces (Ra 0.1μm) and carburized case hardening (depth 0.8-1.2mm) to minimize friction with bushings and prevent shear failure under heavy loads.

• Assembled Joints: Precision interference fit between pins and bushings (0.005-0.01mm interference) to eliminate axial play and reduce transmission backlash to ≤0.03mm per meter of chain.

2.2 Performance Advantages (vs. Standard Roller Chains)

3. Core Technical Specifications

4. Target Engineering Applications

4.1 Construction & Heavy Machinery

• Excavator and loader track drive systems (high torque, shock load resistance)

• Crane hoisting and luffing mechanisms (precision positioning + heavy load capacity)

• Concrete pump truck boom transmission (low backlash + fatigue resistance)

• Pile driver power transmission systems (extreme impact load handling)

4.2 Industrial Processing & Manufacturing

• Steel mill rolling mill drives (high-temperature, heavy-load operation)

• Cement plant kiln and mill conveyors (abrasive, dusty environments)

• Paper mill calender and dryer section drives (precision speed control)

• Mining machinery (ore crusher and conveyor drives – abrasion resistance)

4.3 Power Generation & Energy

• Hydroelectric turbine control systems (precision positioning)

• Wind turbine pitch and yaw drive chains (low maintenance, outdoor durability)

• Biomass power plant boiler feed conveyors (high-temperature resistance)

4.4 Marine & Offshore Engineering

• Ship deck machinery (winches, cranes – corrosion resistance + high load)

• Offshore platform lifting systems (saltwater corrosion resistance + shock loads)

• Marine propulsion auxiliary drives (low backlash + reliability)

5. Quality Assurance & Compliance

• International Standards: Manufactured to ISO 606 (Roller Chains and Bush Chains) – Class K1 (precision grade) and ANSI B29.3 (American Standard for Bush Chains), with full compliance to ISO 9001:2015 quality management systems.

• Rigorous Testing Protocols: Every production batch undergoes:

1. Dimensional inspection (CNC Coordinate Measuring Machine – CMM) for tolerance verification;

2. Tensile strength testing (universal testing machine) to validate load capacity;

3. Fatigue testing (accelerated cyclic load rig) to simulate 10,000+ hours of operation;

4. Wear testing (pin-bushing wear rig) to confirm service life;

5. Ultrasonic inspection of link plates to detect internal defects.

• Material Traceability: All alloy steel components are batch-tracked with mill certificates (EN 10204 3.1) for aerospace, marine, and critical engineering applications.

6. Installation & Maintenance Best Practices

6.1 Installation Guidelines

1. Sprocket Matching: Use precision-machined sprockets (tooth profile tolerance ±0.01mm, hardness HRC 45-50) to maximize chain life and minimize bushing wear.

2. Alignment: Ensure sprocket shafts are parallel (misalignment ≤0.3mm/m) and coplanar (offset ≤0.2mm/m) to avoid uneven bushing wear.

3. Tension Adjustment: Maintain chain tension at 1-1.5% of the chain’s working load limit (avoid over-tensioning, which causes pin/bushing fatigue).

4. Joint Installation: Use factory-supplied connecting links (never weld or modify joints) and torque retaining clips to manufacturer specifications.

6.2 Maintenance Protocols

1. Lubrication: For non-sealed chains, apply high-pressure extreme pressure (EP) gear oil (ISO VG 100) every 500 operating hours; sealed chains require no regular lubrication (inspect every 3,000 hours).

2. Inspection:

• Check bushing wear (replace chain if wear exceeds 0.15mm) every 1,000 hours;

• Inspect link plates for fatigue cracks (use magnetic particle testing) every 2,000 hours;

• Verify pin/bushing fit (replace if axial play exceeds 0.05mm).

3. Replacement: Replace entire chain lengths (never mix new/used segments) to ensure uniform load distribution and prevent premature failure.