Description
Load Chain – 7 × 21 mm for Electric Hoists
High Strength • Precision Engineered • Heat Treated Alloy Steel
The 7 × 21 mm Load Chain is a heavy-duty, precision-manufactured hoist chain designed specifically for electric chain hoists, offering exceptional strength, durability, and smooth operation under demanding lifting conditions. Manufactured from high-grade alloy steel, the chain undergoes a specialised heat-treatment and case-hardening process to maximise wear resistance and fatigue life.
Construction
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Chain Size: 7 × 21 mm
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Type: Load Chain, Grade 80+ or Grade 100 (depending on manufacturer specification)
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Pitch: 21 mm
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Material: High-tensile alloy steel
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Surface Finish: Black oxide / galvanised / electro-zinc (varies by model)
The chain links are precision formed to strict tolerances, ensuring compatibility with leading brands of electric chain hoists.
Key Features
1. High Tensile Strength
The alloy steel composition provides superior load capacity and resistance to deformation, meeting or exceeding international hoist chain standards (ISO, EN, JIS).
2. Heat-Treated for Durability
Controlled heat treatment improves:
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Core strength
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Surface hardness
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Overall fatigue resistance
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Impact resistance under shock loads
3. Smooth, Quiet Hoist Operation
The 7 × 21 profile is optimised to:
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Minimise vibration
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Glide smoothly over hoist pockets
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Reduce wear on internal hoist components
4. Corrosion-Resistant Finish
Black oxide or zinc coating protects the chain against:
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Rust
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Moisture
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Industrial contaminants
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Heavy usage environments
5. Compliant With Safety Standards
Typically manufactured to comply with:
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ISO 3077
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EN 818-7 (fine-tolerance hoist chain)
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JIS B 8812
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Local OHSA lifting regulations
Common Applications
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Electric chain hoists (workshops, factories, construction)
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Goods hoists and lifting machinery
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Manufacturing lines
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Heavy maintenance operations
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Material handling and warehousing
Technical Advantages
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High precision chain pitch ensures perfect pocket engagement
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Exceptional wear resistance reduces long-term maintenance costs
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Maximised load security under repeated lifting cycles
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Suitable for high-frequency and continuous-duty electric hoist applications
Typical Working Load Limits
(These may vary depending on manufacturer and chain grade — can customise once you give me your specs.)
| Chain Size | Pitch | Grade | Approx. WLL | Breaking Load |
|---|---|---|---|---|
| 7 × 21 mm | 21 mm | G80 | ±1.1–1.4 ton | ±4.4–5.6 ton |
| 7 × 21 mm | 21 mm | G100 | ±1.5 ton | ±6+ ton |
Inspection & Maintenance
To ensure safe operation:
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Conduct daily visual inspections for cracks, elongation, corrosion, or deformation
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Perform monthly and annual load chain inspections as per regulations
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Replace the chain if wear exceeds the manufacturer’s allowable tolerance
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Always use OEM-approved chain to avoid hoist malfunction
Why the 7 × 21 mm Load Chain Is Preferred
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Compatible with many modern compact electric hoist designs
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Balances strength and flexibility for smooth pocket engagement
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Reliable for high-duty industrial lifting cycles
