Sizing a lifting chain should be simple, yet most riggers still muddle through incomplete rules and ambiguous "safety margins." Improvising adds expense or, worse, jeopardizes safety. This guide clarifies the confusion. You will discover the three most vital values, scan a brief size matrix, and walk through a six-step process that fixes the choice in less than one minute. Read on, have the checklist handy, and select the perfect Topone G80 lifting chain with confidence.

1 Know the G80 Benefit

Grade 80 alloy chain is strong, ductile, and budget-friendly. Its quench-and-temper strength curve is a minimum of 800 N/mm² breaking stress, so you have a 4 : 1 factor of safety under EN 818-2 and still weld or swap links when on-site damage occurs. Compared to bulky Grade 63 chains, a Topone G80 sling reduces up to 25 % self-weight, so crews fasten hooks quicker and cranes enjoy precious headroom.

2 Take Three Numbers Before You Make a Call Buying

Design Load (DL) – the heaviest routine load, plus the rigging you mean to lift.

Angle Factor (AF) – the factor from EN 818-4 which works out sling leg angle to true line tension.

Required Working Load Limit (RWLL) – just DL × AF. Select AF's first chain whose AF > RWLL and you're within the 4 : 1 rule—no overkill, no short-cuts.

3 Topone G80 Size Matrix—Screenshot It

*WLL values meet EN 818-2 single-leg vertical mode.

Tip: Rig weight per metre adds to DL, while Max OD helps in inspection of tight hook throats or low-headroom cranes.

4 Six-Step Chain-Sizing Flow

List DL from your lift plan—ignore one-off peaks.

Add rigging weight (chain, hook, shackle) + 10 % contingency.

Multiply by AF from EN 818-4 (1.4 at 45°, 2.1 at 60° four-leg, etc.).

Open matrix and choose first Ø with WLL ≥ RWLL.

Check headroom with Max OD—change to lower Ø if clearance doesn't cut it but capacity is still safe.

Record chain ID in your CMMS to mark future inspections.

Complete all six in less than a minute; never guess again.

5 Environment Fine-Tuning

Salt Fog Decks – employ hot-dip zinc; meets 1 000 h neutral-salt spray and slows pitting 5× compared to black lacquer.

Sub-Zero Yards – stay with phosphate coat; impact toughness remains down to −20 °C.

Hot Mills – derate WLL 10 % for loads over 200 °C; G80 still better than G63 at the same temperature.

6 Daily Inspection Checklist

Take the three-minute scan per shift; retire chains at first failed measurement—less expensive than one lost load.

7 Common Sizing Missteps and Fixes

Learn these four and you beat 90 % of sizing errors seen on site.

8 When to Upgrade to G100

Upgrade to Grade 100 if RWLL approaches the 26 mm G80 limit or if sling self-weight hinders workflow. Expect 15 % weight saving but budget for tighter inspection needs and higher buying price.

Figure 1 – Look for the embossed "8 – TPN" stamp for traceability.

Conclusion

Ditch the guesswork—use the six-step flow, consult the matrix, and determine the exact Topone G80 lifting chain your lift needs; purchase TOPONE CHAIN today and lift with absolute confidence.