Sourcing steel threaded inserts from China

UK duty and classification for threaded inserts

Heading 7318 covers iron or steel fasteners and similar articles. This guide focuses on steel threaded inserts, including blind rivet nuts, solid inserts and wire thread inserts. The table gives relevant tariff descriptions, rather than a universal classification for every insert. See the wider fastener guide for screws, nuts and washers. For steel blind rivets, see our steel blind rivet sourcing guide. For dowel pins, see our steel dowel pin sourcing guide. For suspension fasteners, see our suspension U-bolt sourcing guide. For spring washers, see our steel spring washer sourcing guide.

Read from the UK Trade Tariff on 8 October 2026, all selected lines carried 0% duty for goods from China. The supplied tariff snapshot lists no anti-dumping or countervailing duty, steel trade measure, suspension or attached import control on these lines.

Confirm the commodity code using the drawing, material and fastening method. Distinguish a blind rivet nut from another nut or another threaded article before choosing a table row. The commodity code is used on the import declaration; send your customs broker the actual design rather than only the supplier's product name.

Specify the insert and its receiving material

State whether you need a blind rivet nut, solid threaded insert or wire thread insert. Specify steel grade, internal thread form and pitch, installed length, coating and receiving material. For rivet nuts, define head style, body shape, open or closed end, hole size and grip range. For solid and wire inserts, agree the receiving-hole preparation, installation tool and locking arrangement.

Agree acceptance checks using the actual panel, casting or furniture component. Include thread gauging, installation settings, resistance to rotation and pull-out testing where relevant. Ask for material and coating records linked to the production batch, and retain approved samples for comparison.

UK REACH restrictions can limit, ban or set conditions on substances in articles. Ask for the alloy, plating and passivation details so applicable restrictions can be checked. If inserts are supplied as consumer repair products in Great Britain, they must be safe in normal or reasonably foreseeable use.

Worked duty example

Illustrative example, not a quote: Illustrative mixed-size batch of stainless steel blind rivet nuts; values are illustrative under 7318 16 31 90, invoiced at £4,000 free on board, with £300 of freight and insurance to the UK. The customs value is £4,300. Duty at 0% is £0. Import VAT at 20% is charged on the customs value plus duty, £4,300, so it is £860. With no duty, the only import tax is the VAT, which a VAT-registered importer can usually reclaim. The import duty and VAT guide explains each step.

Inspection checklist

Threads: check sampled internal threads with the agreed gauges and mating screws after installation, not only before setting the insert.

Fit: measure body diameter, length and head dimensions against the drawing; trial-install rivet nuts in the specified panel thickness and hole shape.

Retention: check for spinning, cracked bodies, stripped threads and pull-out against the agreed test method and acceptance criteria.

Finish and batches: check coating coverage, burrs, rust and damage on arrival; match carton labels and material records to each size and batch. Use the quality inspection guide to plan checks.

What goes wrong

An insert can accept a screw on the bench yet fail after installation. Excessive setting force distorts rivet nut threads, the wrong grip range leaves a loose joint, and an oversized hole allows the body to spin. Solid inserts can split the receiving material when the pilot hole is wrong; wire inserts can sit proud or leave an installation tang where removal was specified.

Approve installed samples in the intended receiving material before releasing production. Record the installation method and separate mixed sizes on arrival. A generic thread description or coating certificate does not establish that the supplied batch matches the approved assembly.

Cambridge China Bridge sources these products for UK businesses, checking the factory and the documents before shipment. See factory verification. For repeat volumes, see container programmes.