Grade 70, 80, and 100 Chain: How the Grades Differ and When Each Applies

The number stamped into a chain link is not a working load limit. It's a grade designation that points to material category, nominal strength class, and whether that chain is rated for overhead lifting at all.

Procurement managers ordering chain for overhead sling assemblies sometimes pull Grade 70 because it's widely stocked, yellow chromate coated, and often cheaper per foot than alloy alternatives. Grade 70 is a transport chain, designed for cargo securement on flatbed trucks, not for lifting loads overhead. Grades 80 and 100 are alloy grades that carry overhead lifting ratings.

This guide covers what the grade number means, how Grades 70, 80, and 100 differ in material and application, field marking conventions, and the context for choosing between Grade 80 and Grade 100.

Ratings and examples here are for safety awareness. Final lift plans and gear selection typically follow applicable standards, manufacturer data, and engineered lift planning where required.

What the Grade Number Actually Means

Chain grade is a nominal strength classification. The number approximates 10 MPa of minimum tensile strength per the NACM Welded Steel Chain Specifications, so Grade 80 corresponds to roughly 800 MPa, and Grade 100 to roughly 1,000 MPa. These are classification tiers, not precise conversions. NACM specifies proof load and break test requirements per grade, and ASME B30.9 (Slings) covers alloy chain slings in overhead lifting service.

What the grade number does not convey is working load limit (WLL). WLL is configuration-dependent: it varies by chain diameter, leg count, sling angle, and end fittings. OEM rating tables (Crosby, Peerless, Pewag, Gunnebo, CM) translate grade into WLL for a specific assembly.

Grade equals material and strength class. WLL equals the load rating for a configured assembly, per manufacturer documentation. Keep the two separate.

Grade 70: Transport Chain, Not a Lifting Chain

Grade 70 chain is commonly called "transport chain" or "trucker's chain." It's the standard for cargo securement on flatbed trailers and is governed by Federal Motor Carrier Safety Administration (FMCSA) tie-down regulations, not by lifting standards.

Grade 70 is typically identified in the field by its gold or yellow-chromate finish. Manufacturers stamp "G70," "70," "700," or "7" into the links.

Grade 70 is not rated for overhead lifting. It does not appear in ASME B30.9 overhead lifting chain sling tables. It's not an alloy chain in the sense that Grades 80 and 100 are, the heat treatment and alloy composition that give Grades 80 and 100 their overhead-lifting ratings aren't present in Grade 70 to the same specification. Using Grade 70 in an overhead lifting application is an application error regardless of whether it appears to have adequate strength for the load in question.

Grade 80: The Standard Alloy Overhead Lifting Chain

Grade 80 is manufactured from heat-treated alloy steel. It's the most widely used overhead lifting chain in industrial environments, crane rigging, chain slings, below-the-hook assemblies, and general lifting applications in mills, shipyards, fabrication shops, and industrial job sites.

Grade 80 chain slings operate under ASME B30.9 (Slings). The standard covers inspection criteria, sling angle considerations, end-fitting compatibility, and marking requirements. ASME B30.9 doesn't prescribe a single WLL for a given chain diameter, that comes from the OEM's published rating tables for the specific chain product and configuration.

Field identification: Grade 80 chain is typically marked with "G80," "80," or "800" stamped into the links at regular intervals. Many manufacturers also use a colored tag or master link identifier to identify grade at the hook-end of a sling assembly. Yellow or orange master links are common on Grade 80 assemblies, though color conventions vary by manufacturer, the stamped link marking is the authoritative identifier, not the color.

Grade 80 and Grade 100 alloy chain are the grades Holloway Houston manufactures into single-leg, double-leg, and quad-leg chain slings, with three-leg assemblies made on request. Chain is also sold by the foot in both grades for custom assembly and maintenance replacement.

Grade 100: Higher-Strength Alloy for Demanding Applications

Grade 100 chain uses a higher-strength alloy and heat-treatment specification than Grade 80. At the same chain diameter and configuration, Grade 100 carries a higher working load limit than Grade 80, per OEM manufacturer rating tables.

The practical implication is that a Grade 100 chain sling at a given diameter can handle a heavier load than a Grade 80 sling at the same diameter. Alternatively, a lighter-diameter Grade 100 chain can be selected where a heavier Grade 80 chain would otherwise be required, reducing sling weight while maintaining the needed capacity. That weight reduction matters in applications where the crane is working near capacity or where the rigging crew is handling the sling assembly manually on high-frequency lift cycles.

Field identification: Grade 100 chain is typically marked "G100," "100," or "1000" stamped into the links. Manufacturer master link color conventions for Grade 100 vary, red master links appear on Grade 100 assemblies from several major manufacturers, but the stamped link marking remains the definitive identifier.

Grade 100 chain slings are also governed by ASME B30.9 for overhead lifting applications.

Grade Comparison at a Glance

WLL is configuration-dependent. See OEM rating tables (Crosby, Peerless, Pewag, Gunnebo, CM) for specific diameter, leg count, and sling angle values.

When Grade 80 vs. Grade 100 Applies

The decision between Grade 80 and Grade 100 is generally driven by three factors.

Capacity requirement at a given chain diameter. When the load pushes against the upper end of what Grade 80 will carry at a specific diameter, Grade 100 at the same diameter provides additional headroom. The specific WLL numbers for each configuration come from OEM rating tables, not from the grade number alone.

Assembly weight. Grade 100 chain at a smaller diameter may match the capacity of Grade 80 at a larger diameter, with lower sling assembly weight. On applications with repeated manual handling of the sling, or where the crane's available lift capacity is constrained by rigging weight, a higher-grade, smaller-diameter chain may be preferred.

Compatibility with existing fittings. Switching grades mid-assembly is not a neutral choice. Master links, hooks, shackles, and coupling links are rated by manufacturers for specific grade chain. A Grade 80 hook is not automatically rated for Grade 100 chain at the same load.

The fit decision belongs to the lift engineer or qualified rigger working from manufacturer charts and site conditions, not to this article. What this article provides is the framework for understanding why the grades differ and what each is designed for.

Inspection Applies to All Grades in Lifting Service

Chain in overhead lifting service, whether Grade 80 or Grade 100, whether in a chain sling or a single-leg bridle, is subject to periodic inspection per ASME B30.9. Inspection programs typically examine wear, elongation, link distortion, cracks, gouges, corrosion, and legibility of the grade marking. A chain where the grade stamp is no longer readable is a chain that cannot be confirmed as the correct grade for the application.

Holloway Houston offers rigging inspection services for chain slings and lifting assemblies. If you're working through a periodic inspection or have inherited a mixed inventory where grade identification is uncertain, our team can help.

Conclusion

Grade 70, Grade 80, and Grade 100 chain look similar on a shelf. The grade stamp on each link is what separates a transport chain from an overhead lifting assembly, a fundamental application boundary, not a technical nuance. Grades 80 and 100 are overhead lifting grades; Grade 70 is not.

For chain slings, chain by the foot, or rigging inspection, call Holloway Houston at 1-888-496-4700.