What it is
Electric-resistance-welded (ERW) pipe is formed from strip and seam-welded, used for structural, scaffolding, water, and low-pressure applications. It is cheaper than seamless, so the frauds here are wall-thickness shortfall and, for galvanized pipe, thin zinc.
Grades & standards buyers order
| Grade | Standard | Notes |
|---|---|---|
| ASTM A53 (welded) | ASTM A53 | General welded pipe grade. |
| Q195 / Q235 | GB | Chinese structural pipe grades. |
| BS 1387 | BS 1387 | Common for galvanized water pipe. |
How it's sold: Sold by metric ton or per length; specify OD, wall thickness, ends (plain/threaded), and galvanizing if required.
What drives the price
- Strip (HRC) cost
- Wall thickness
- Galvanizing and coating weight (if GI pipe)
- End finishing and threading
Lock these into the contract before you pay
Wall thickness and tolerance
Thin wall invoiced at full thickness is the core ERW loss.
Galvanizing coating weight
GI pipe under-coating mirrors GI coil fraud — specify g/m².
Weld quality / hydrostatic test
Require the weld test for any pressure or water use.
Scams most common to welded pipe
Coating-Weight & Galvanizing Fraud
Galvanized pipe with zinc far below the quoted coating weight.
Grade Substitution (lower grade shipped than ordered)
Thinner wall or lower grade than the PO, hidden by nominal-size invoicing.
Fake Third-Party Inspection Report
A fabricated hydrostatic/weld test report for pipe that was never tested.
Red flags in a quote or sample
- Wall thickness stated only as nominal, no tolerance
- Galvanized pipe with no coating-weight figure
- No hydrostatic test offered for water/pressure pipe
Already paid and something's wrong?
If you received off-spec welded pipe, a certificate that doesn't match, or your supplier has gone quiet after a deposit, move quickly. Recovery odds drop with every day that passes on a wire transfer.
Buying welded pipe from China: FAQ
What grades of welded pipe can I buy from China?
The most commonly ordered grades are ASTM A53 (welded), Q195 / Q235, BS 1387. Always pair the grade with its standard on the purchase order so the mill test certificate can be matched to what you actually receive.
What is the most common scam when buying welded pipe from China?
Coating-Weight & Galvanizing Fraud. For this product specifically: Galvanized pipe with zinc far below the quoted coating weight. The defense is to specify the exact grade and standard, require a verifiable mill test certificate, and commission independent pre-shipment inspection.
What should I check before paying for welded pipe?
Lock down wall thickness and tolerance, galvanizing coating weight, weld quality / hydrostatic test in the contract, verify the supplier is a real manufacturer, and never release the balance until an independent inspection confirms the goods.
I already paid a Chinese supplier for welded pipe — what now?
Act fast: contact your bank about a recall on the wire, gather all contracts and communications, report the pattern so others are warned, and review the documented cases to understand your options. The sooner you act on a redirected or disappeared payment, the better the odds.
Related product guides
Seamless pipe
Pipe with no weld seam for pressure and boiler service. Seamless-vs-welded substitution and wall-thickness shortfall are critical safety risks.
Scaffold tube
Galvanized tube for access scaffolding — a safety-critical product where wall and coating shortfall create real danger.
HR coil
The base flat product for tubes, plate, and re-rolling. Grade substitution and thickness/gauge shortfall are the primary risks.