What is HRPO pickled and oiled steel?
HRPO — hot-rolled, pickled and oiled — is a surface condition, not a steel grade. Hot-rolled coil leaves the mill covered with a blue-black oxide scale; the coil is uncoiled through a hydrochloric-acid pickling line that dissolves the scale, rinsed, dried, given a thin rust-preventive oil film and recoiled. What comes out is the same S235JR or DD11 steel with a uniform grey-metallic surface, ready for forming or painting. Three things follow. The scale that would crack off in a press brake or a roll-former, damaging tools and the part, is gone. Paint and powder adhere after simple degreasing — no shot-blasting. And the thickness tolerance is unchanged from hot-rolled (EN 10051), so HRPO is not a substitute for cold-rolled where gauge precision matters, but between 1.5 and 6 mm it is the economical clean sheet: cheaper than cold-rolled, cleaner than black. Tube mills run HRPO strip almost exclusively; so do roll-formers making C/Z profiles, trailer and body builders pressing brackets and cross-members, and enclosure makers in the thicker gauges. The substrate grade is chosen by use: S235JR (ST37) for general fabrication and tubes, DD11 for bending and forming, DD13/DD14 for drawing, and S355MC–S700MC for high-strength parts. All are available pickled from Turkish mills and stocked in the common gauges at Dilovası.
Chemical composition
| Element | S235JR: C | S235JR: Mn | S235JR: P / S | DD11: C | DD11: Mn | DD11: P / S |
|---|---|---|---|---|---|---|
| max. % (ladle) | 0.17 | 1.40 | 0.035 / 0.035 | 0.12 | 0.60 | 0.045 / 0.045 |
Pickling does not change the chemistry; the certificate carries the substrate grade with the note "pickled and oiled".
Mechanical properties of the substrates
| Substrate | Yield (MPa) | Tensile (MPa) | Elongation | Use |
|---|---|---|---|---|
| S235JR (ST37) | ≥ 235 | 360–510 | ≥ 26 % (A5) / 19 % (A80) | general, tubes, welded parts |
| DD11 | 170–340 | ≤ 440 | ≥ 28 % (A80) | bending, roll-forming |
| DD12 | 170–320 | ≤ 420 | ≥ 30 % | drawing |
| DD13 | 170–310 | ≤ 400 | ≥ 33 % | deep drawing |
| DD14 | 170–290 | ≤ 380 | ≥ 36 % | extra-deep drawing |
| S355MC | ≥ 355 | 430–550 | ≥ 19 % | high-strength forming |
Equivalent grades
| System | Grade | Note |
|---|---|---|
| Trade | HRPO / P&O / HRP / asitli sac | same condition |
| ASTM | A1011 HRPO (CS / DS / SS grades) | US designation |
| JIS | SPHC-P / SPHD-P | pickled hot-rolled |
| EN | S235JR+P&O, DD11+P&O | certificate wording |
| Cold-rolled | DC01 | cleaner, tighter gauge, thinner, dearer |
Pickling, oiling and surface
| Condition | Process | Surface | Best for |
|---|---|---|---|
| Black (HR, as-rolled) | none — mill scale left on | blue-black oxide, 10–40 µm, flakes when bent | welded structures, plate to be blasted, hidden parts |
| HRPO (pickled & oiled) | HCl pickling of coil, rinse, light oil | uniform grey-metallic, scale-free, Ra ≈ 1–3 µm | forming, painting, roll-forming, tube making, visible parts |
| HRP / HRPO skin-passed | pickling + temper pass | flatter, tighter gauge, no Lüders lines | pressing, blanking, precision parts |
| Dry (pickled, unoiled) | pickling, no oil | bare, rusts within days | immediate galvanizing or welding only |
Turkish trade names: siyah sac = black hot-rolled, HRP / asitli sac = pickled and oiled. The steel grade underneath (S235JR, DD11 and so on) is identical — only the finish differs, and only the finish is priced.
Thickness range and stock sizes
| Thickness | Widths × lengths | Availability |
|---|---|---|
| 1.35–2.0 mm | coil 1 000 / 1 250 / 1 500 mm; sheet to 3 000; slit strips | stock S235JR, DD11 |
| 2.5–4.0 mm | coil 1 250 / 1 500 mm; sheet 2 500 / 3 000 / 6 000 | stock S235JR |
| 5.0–6.0 mm | coil 1 500 mm; sheet 1 500 × 6 000 | stock, limited |
| 8–12 mm pickled | coil / sheet | to order 2–3 weeks |
| MC grades pickled | coil 1 250 / 1 500 mm | to order 2–3 weeks |
Weight per m² and per sheet
| Thickness | kg/m² | 1 000 × 2 000 (kg) | 1 250 × 2 500 (kg) | 1 500 × 3 000 (kg) |
|---|---|---|---|---|
| 1.35 mm | 10.60 | 21.2 | 33.1 | 47.7 |
| 1.5 mm | 11.78 | 23.6 | 36.8 | 53.0 |
| 1.8 mm | 14.13 | 28.3 | 44.2 | 63.6 |
| 2 mm | 15.70 | 31.4 | 49.1 | 70.7 |
| 2.5 mm | 19.63 | 39.3 | 61.3 | 88.3 |
| 3 mm | 23.55 | 47.1 | 73.6 | 106.0 |
| 4 mm | 31.40 | 62.8 | 98.1 | 141.3 |
| 5 mm | 39.25 | 78.5 | 122.7 | 176.6 |
| 6 mm | 47.10 | 94.2 | 147.2 | 212.0 |
Uncoated; tolerances to EN 10051 (e.g. ±0.17 mm at 2.0 mm, 1 250 wide). Oil film ≈ 1 g/m² per side, not weighed.
Forming, welding and painting
Bends at 1 × t (S235JR) or 0.5 × t (DD11) without scale cracking; roll-forms and tube-welds cleanly — the clean edge is why ERW mills insist on pickled strip. Punching and laser cutting are cleaner than on black sheet (no scale spatter). Welds like the substrate grade; wipe the oil near the joint. Painting: alkaline degrease, then primer or powder — no blasting needed; phosphating for e-coat. The oil film protects for 3–6 months indoors; store dry and use in rotation.
Where it is used
- ERW tube and hollow-section strip (slit to width)
- C, Z, sigma and omega roll-formed profiles
- Trailer, truck-body and agricultural pressings
- Enclosures, cabinets and machine covers in 1.5–4 mm
- Laser-cut and punched parts for painting
- Wheel rims, drums and formed automotive parts (DD grades)
HRPO vs black hot-rolled vs cold-rolled
Black (HR) is cheapest and fine for welded structures and anything blasted before paint — see hot-rolled coil and sheet. HRPO adds 15–25 USD/t for pickling and gives a clean, formable, paintable surface in 1.35–6 mm. Cold-rolled (DC01) is thinner (0.4–3 mm), flatter, with a finer surface and tighter gauge, at 60–100 USD/t more. Rule: hidden and welded → black; formed or painted, 1.5–6 mm → HRPO; thin, precise or visible → cold-rolled.
Price
HRPO is priced at the hot-rolled coil list plus the pickling charge; the bands below are the month's indicative FOB Istanbul ranges for the thin and thick stock. DD grades add 10–30 USD/t by level; slitting and cut-to-length per ton.
Bands from our weekly export list (September 2026), FOB Istanbul, full-container quantities, excluding freight and certificates. Firm price per project on RFQ within one working day.
Export and packing
Packing for HRPO pickled and oiled steel: coil eye-to-sky, VCI paper; sheet on skids ≤ 3 t, interleaved; slit coils on pallets. Loading: 20' one coil ≤ 20 t; 40' HC two coils or 24 t sheet. Tariff heading follows the surface: 7208 hot-rolled, 7209 cold-rolled, 7210 coated, 7225 / 7226 alloy.
| Term | Detail |
|---|---|
| MOQ | One coil (10–25 t) or 5 t of sheet |
| Incoterms | FOB Istanbul · CIF / CFR Gulf, Africa · DAP EU, Balkans, Iraq, Caucasus · DAP Aktau |
| Lead time | Stock 1.35–6.0 mm: 3–5 working days; slit strip and cut blanks 5–8 days |
| Packing | Coil eye-to-sky, VCI paper; sheet on skids ≤ 3 t, interleaved; slit coils on pallets |
| Container / truck | 20' one coil ≤ 20 t; 40' HC two coils or 24 t sheet |
| Documents | Invoice, packing list, EN 10204 3.1 (3.2 on request), certificate of origin; SASO / SONCAP / PVoC on request |
| Payment | 30% advance, balance against B/L copy; L/C at sight for orders above 100 t |
Certificates and testing
HRPO pickled and oiled steel is supplied with an EN 10204 3.1 mill certificate tied to the coil number printed on the pack list. A 3.2 certificate with SGS, TÜV or BV in attendance is arranged on request. Retained samples are held for six months so that a later claim can be checked against the same coil.
How to order
Specify substrate grade (S235JR / DD11 / DD13 …), thickness × width (or slit widths / sheet length), oiling (standard light oil, heavy oil for long storage, dry for immediate galvanizing), coil weight limit and tonnage.
Standards
- EN 10025-2 S235JR / EN 10111 DD11–DD14 (substrate)
- EN 10051 — dimensions and tolerances of hot-rolled strip
- EN 10163-2 — surface class
- EN 10204 3.1
Grades
Grade data sheets (chemistry, mechanicals, equivalents) are on our reference site: S235JR · DD11 · S355MC
Frequently asked questions
What is HRPO steel?
Hot-Rolled Pickled and Oiled — hot-rolled sheet or coil whose mill scale has been removed by acid pickling and which is lightly oiled against rust; a surface condition available on S235JR, DD11–DD14 and MC grades.
What is the difference between HRPO and HRC?
HRC (hot-rolled coil, black) still carries its mill scale; HRPO has been pickled clean and oiled. Same steel and tolerances; HRPO costs 15–25 USD/t more and is used for forming, tubes and painting.
What is the difference between HRPO and cold-rolled?
Cold-rolled (DC01) is rolled again after pickling to a thinner gauge with a smoother surface and tighter tolerance; HRPO keeps hot-rolled gauge and tolerances. HRPO covers 1.35–6 mm, cold-rolled 0.4–3 mm.
What is asitli sac / HRP sac?
The Turkish names for pickled-and-oiled hot-rolled sheet — the same product as HRPO.
Can HRPO be painted without blasting?
Yes — after alkaline degreasing it takes primer, powder or e-coat directly; that is its main advantage over black sheet.
What HRPO thicknesses are in stock?
1.35–6.0 mm in 1 000–1 500 mm widths as coil, sheet and slit strip at Dilovası; thicker and MC grades pickled to order.