Choosing a lifting chain traditionally becomes a struggle between cost limitations and safety factors. Select too small and face downtime; select too large and spend money and handling time. This manual un-clouds Topone G80 lifting chains in plain language, describes how diameter, working load limit (WLL) and link weight relate to each other, and outlines a step-by-step sizing procedure. Read on, compare actual numbers, and depart with a chain spec that fits your hook, meets the standard, and saves you money.

1. Why G80 Still Reigns Everyday Rigging

Grade 80 steel has a balance between strength, toughness, and weldability. You've got your 4:1 safety factor under EN 818-2 without the increased hardness that makes Grade 100 hard to repair on site. Where you're doing repeated lifts under 32 tonnes and need fast hook compatibility, G80 enters on cost-per-cycle.

2. Identify the Three Numbers That Govern Sizing

Design Load – the maximum weight that you actually lift, plus rigging weight.

Working Load Limit (WLL) – catalogue value under plain pull at 0–60 °C.

Chain Angle – angle of sling leg; smaller angles induce higher tension.

Bench-mark design load by angle factor in EN 818-4, and select the first chain size whose WLL is greater than that value.

3. Topone G80 Chain Range at a Glance

Below you’ll find the core metric sizes stocked by Xintai Taida Mirso’s nine automated lines. All chains receive full-length quench-and-temper treatment .

4. Reading the Chart Correctly

WLL includes the 4:1 safety factor; never exceed it.

Proof Load verifies weld quality at the factory—operators never touch it on site.

Weight per metre matters when you're lifting long sling legs; add it to the payload.

5. Common Sizing Mistakes—and How to Avoid Them

Use a written checklist so fatigue or night shift pressure never skips a step.

6. Field Measurement Cheat-Sheet

Topone proposes a pocket vernier with rounded jaws and a five-link go/no-go gauge plate. Use a mid-link diameter from the direction opposite the weld; reject if 10 % loss is observed. Then put five consecutive links on a flat surface and take gauge length; scrap chain if length increases 3 % above nominal. Finish with a flashlight examination for cracks and rust blisters. The whole routine takes three minutes and eliminates hours of rigging drama.

7. When to Convert to G100 Instead

Convert to Grade 100 when lift weight or angle thrust calculated tension beyond the top of Table 1. The lighter G100 chain saves about 15 % in sling weight, handy for high-cycle warehouse jib cranes. But weigh that saving against more extensive weld processes and more demanding maintenance.

8. Handling and Storage Tips

Clean and lubricate after each muddy shift; grit doubles link wear.

Hang chains, not coil on wet floors.

Log service hours; retire at first of five years or 10 % wear.

9. Quick Visual ID Guide

Figure 1 – Check for orange link stamp "8 — TPN" with heat number for batch traceability.

Orange powder coat resists 480-hour salt spray but scratches reveal glossy steel, prompting inspectors to check for wear.

10. Step-By-Step Sizing Flow

Log each lift weight for each shift.

Add rigging weight with 10 % contingency.

Multiply by angle factor (see EN 818-4 table).

Open Table 1; choose diameter with WLL ≥ result.

Check hook throat is appropriate for chosen chain.

Record weight per metre for sling-leg mass.

Record decision in your rigging log.

Do the steps, and you are assured of compliance as well as cost control.

Conclusion

You now have a functional guide to select a Topone G80 lifting chain that represents real loads without losing steel or dollars—move from theory to practice and see how the right size enhances safety, lessens fatigue and speeds every lift, so choose Topone CHAIN today.