1. Show the “price ruler” first
Using our mill’s (Ji-X Traffic Facilities — three 480 m continuous roll-forming lines) factory ledger on 20 Sep 2025 as an example: common section YT6118, substrate TS280GD+Z, 275 g/m², yield ≥ 280 MPa. Settled by foot (FOB Tianjin):
1.0 mm thickness: USD 4.8 / ft (FOB Tianjin)
1.5 mm: USD 6.2 / ft
2.0 mm: USD 7.9 / ft
2.5 mm: USD 9.8 / ft
At an exchange rate of ¥7.1/USD this equals roughly ¥34–70 / ft. If priced by finished-arch tonne, factory prices are ¥5,050–5,350 / t — roughly aligned with hot-rolled coil spot + ¥550 processing. Every +0.5 mm thickness raises per-foot cost by about ~20% — thickness is the single most price-sensitive variable.
Note: these “corrugated steel arch pipes” are also commonly referred to as corrugated metal arch pipes, corrugated steel culvert pipes, corrugated arch sections, corrugated arch pipe segments — you may see these aliases in different quotes and specs.
2. Six switches that set the per-foot price
Steel raw material
A price gap of ¥180/t between plain hot coil Q235 and structural steel TS280 pushes the per-foot price up ~¥0.6. Increasing galvanizing from 275 g → 350 g adds ~¥280/t, another ~¥0.9/ft.
Section profile (model)
YT6118 (typical spans 6–18 m) vs YT8532 (spans 20–30 m): for the same thickness the latter’s developed width increases ~32%, so the per-foot price naturally rises 30%+.
Corrosion protection level
“Galvanized + epoxy sealing” costs ~12% more than plain galvanizing; adding a 40 μm fluorocarbon topcoat brings total up ~18%. In C5-M coastal environments owners commonly specify galvanized + epoxy + fluorocarbon — not negotiable.
Order length (run length)
One 12 m mother coil yields about 110 ft continuous arch pipe. For orders <500 ft, setup and head/tail scrap exceed 8% — factories spread that scrap into the quote. For single runs ≥2,000 ft, scrap falls <2% and per-ft price can drop 3–4%.
Packaging & delivery
Loose bulk sheets are cheapest. If buyer requests “10 pieces per bundle, steel frame + fumigated timber pallet, corner protectors for export”, packaging adds ~¥1.2 / ft. With container weight limits (21 t), 2.0 mm arches can only load 18 m × 12 pcs per container, adding about ¥1.4 / ft in freight allocation.
Market timing (price tick)
Using hot coil spot ¥3,760 / t (Sept 2025) as baseline: if the Shanghai futures main contract rises ¥200, factories typically lift per-foot price ¥0.7–0.8 the same week. Coil stocking cycles are 15–20 days, so locking steel at a trough can save ~5–6% of total cost.
3. Field cases for reference
Case 1 — Jiangshan grain-store canopy (2020 tender)
Span 17.8 m, length 72.2 m, four consecutive arches, 1.0 mm plate, galvanized 275 g. Project cap price ¥1,114,700 — ≈ ¥68 / ft turnkey (manufacture + transport + install + accessories). Factory material-only price at the time was ~¥38 / ft, so installation & accessories took the remaining ~¥30 / ft.
Case 2 — Inner Mongolia provincial road culvert (delivered 2025-08)
Span 3.0 m, corrugation 381 mm, 2.5 mm plate, hot-dip galvanized 350 g, qty 1,800 ft. Factory FOB Tianjin quoted USD 9.8 / ft, customer picked up loose. Doubling thickness roughly doubled price in this example.
4. Procurement channels & who to negotiate with
Direct from factory
Pros: Lowest prices, custom lengths, adjustable galvanizing weight; MOQ ≥500 ft; usual terms 30% deposit + balance before shipment.
Cons: Buyer handles transport and export formalities.
Steel-structure exporters / trading houses
Pros: Small-lot consolidation, one-stop documentation & export handling.
Cons: 6–8% premium vs factory, lead time +5–7 days.
Local metal supermarkets
Pros: Spot availability (mainly 1.0 / 1.5 mm), cut-to-size, same-day pickup.
Cons: 12–15% higher than factory, limited section types.
EPC main contractor with supply clause
Large highway EPCs often bundle corrugated pipes into “minor structures” and run their own sub-bids. Factories may concede ~3% for big orders but typically include a “steel price adjustment clause” so if hot coil rises >5% they automatically claim the difference next month.
5. Three practical tips for procurement managers
Lock the spec: freeze span + rise + plate thickness + corrosion spec and ask factories for a per-foot quote. This avoids the trap of “cheap tonne price but wider developed width” that inflates per-foot cost.
If project >6 months, sign a “hot-coil average price + processing fee” hedging agreement with a steel mill — can save 3–5% versus spot buys.
For export orders confirm packaging precisely: loose container shipments suffer salt spray and bumps; on-site re-zincing can swallow ~10% of raw material savings.
6. Conclusion
The corrugated steel arch pipes price is not mystical — five factors determine the range: thickness, section profile, corrosion protection, order quantity, and market timing. Spot range in Sept-2025: USD 4.8–9.8 / ft (≈ ¥34–70 / ft). Larger span, thicker plate and higher corrosion spec take you toward the top end. Give the factory full demand parameters at once and they can return a per-ft quote accurate to $0.1 / ft — a true advantage of digitized production planning.