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How to Specify G70 Transport Chain: Diameter, Finish and End Fittings
G70 is the grade most truck operators reach for, but specifying it means more than picking a diameter. What the grade promises, what the yellow finish signals, and what to settle at ordering.
Grade 70 is the grade most load-securement buyers ask for by name, which makes it easy to order on the number alone. But the grade only sets the strength class. What gets delivered depends on the diameter, the finish, and the end fittings that turn a length of chain into a tie-down.
What G70 Actually Promises
G70 is the American standard chain for load securement. It is alloy steel, heat treated after the chain is formed, and it carries a grade marking that identifies it as chain intended for securing cargo on trucks, trailers and flatbeds, and for towing.
Two limits worth stating together. The marking says the chain is made for load securement, not that it is lifting chain: G70 is not a grade-marked overhead lifting chain and must not be used for lifting. And the grade is a class, not a capacity: a G70 chain in one diameter does not carry the same load as one in another. See G70 transport chain and cargo securing covers it in context.
Choosing the Diameter
The diameter is set by the load to be secured. Standard production for G70 runs from 7 mm to 16 mm diameter with working load limits from about 1,430 kg to 7,170 kg across that range: the bottom covers light trailers and small equipment, the top covers heavy plant on a low loader.
Two points follow. Tie-down load is not lifted load: a chain holding a machine on a trailer sees shock and vibration, so the margin is a judgment about duty, not a formula. And the fittings must match the chain; a hook rated below the chain makes the chain capacity irrelevant.
Why the Finish Is Yellow
Grade 70 transport chain is conventionally finished in yellow zinc chromate, and the colour does two jobs. It is a colour code: in North America a yellow chain on a truck is understood to be G70. And it is a coating, giving corrosion protection on a chain that lives outdoors on a flatbed.
Do not treat the colour as decoration. Chain supplied uncoloured to a market that reads yellow as the G70 signal at a roadside inspection has lost part of its marking function. In a yard where the colour carries no meaning, choose the finish on corrosion grounds instead. Both are legitimate; decide which applies before ordering.
End Fittings Turn Chain Into a Tie-Down
A length of G70 is not yet a load securement system. The end fittings complete it: hooks that seat on a stake pocket or a D-ring, and tensioners or binders that take up slack. The chain carries the load; the fittings decide whether it can be attached.
This is where a specification goes wrong quietly: the chain is ordered by grade and diameter, the fittings are sourced separately, and the two arrive with different ratings or incompatible geometry. Ordering them together removes the mismatch.
What to Put on the Order
Frequently Asked Questions
What does the yellow colour on G70 mean?
Yellow zinc chromate is the conventional colour coding for grade 70 transport chain, and it also gives corrosion protection. The colour signals the grade in markets that read it that way; it is not decoration.
Can G70 transport chain be used for lifting?
No. G70 is load securement chain, not a grade-marked overhead lifting chain, and must not be used for lifting or for suspending a load above people.
Boyuan Metal supplies grade 70 transport chain in alloy steel, heat treated after forming, with an electro galvanized yellow zinc chromated finish, in diameters from 7 mm to 16 mm. Tell us the load to be secured, the market it ships to and the fittings you need, and we will confirm the specification.