Se lavori nel settore manifatturiero, costruzione, o ingegneria automobilistica, pickled and oiled steel (Acciaio PO) è un punto di svolta per i progetti che necessitano di pulizia, rust-resistant, e metallo facile da lavorare. A differenza dell'acciaio grezzo laminato a caldo, L'acciaio PO ha una superficie liscia, superficie priva di incrostazioni, che la rende ideale per lo stampaggio, saldatura, or painting. Questa guida analizza tutto ciò che devi sapere per scegliere, utilizzo, and source PO steel effectively.
1. Pickled & Oiled Steel Products: Forms for Every Project
PO steel comes in versatile shapes tailored to different industrial needs. Knowing which product to pick saves time and reduces waste. Ecco un riepilogo:
| Product Type | Caratteristiche principali | Usi comuni |
|---|---|---|
| Hot rolled pickled and oiled steel coil | Continuous rolls (width 100–2000mm), conveniente | Produzione di massa (per esempio., parti di telai automobilistici) |
| Pickled and oiled steel sheet | Flat, cut to standard sizes (1m×2m, 2m×4m) | Storage tank panels, agricultural equipment parts |
| Pickled and oiled steel plate | Spesso (6–50 mm), durevole | Structural components for heavy machinery |
| Pickled and oiled steel strip | Narrow (larghezza <100mm), preciso | Raccordi per tubi, small stamped parts |
| Slit pickled and oiled steel coil widths | Custom-slit coils (per esempio., 50mm, 75mm) | Finiture automobilistiche, involucri elettrici |
Real Example: A tractor manufacturer usespickled and oiled steel sheet for its machine bodies. The smooth surface accepts paint evenly, and the oil coating prevents rust during storage—cutting rework costs by 15%.
2. Pickling & Oil-Coating Process: How PO Steel Is Made
The PO steel process transforms rough hot-rolled steel into a high-quality material in 5 key steps. Each stage ensures a clean, flat, and protected surface:
- Hot-Rolled Steel Preparation: Start with hot-rolled steel (from a blast furnace), which has a thick, flaky oxide layer (“scale”) on its surface.
- Acid Pickling Line: The steel is dipped in a bath of either acido cloridrico O acido solforico (30–40% concentration) at 60–80°C. This dissolves the scale—hydrochloric acid works faster (10–15 minutes vs. 20–25 for sulfuric) and leaves a smoother surface.
- Rinsing & Essiccazione: After pickling, the steel is rinsed with water to remove acid residue (prevents pitting) and dried with hot air.
- Tension Leveling: The steel passes through rollers under tension to fix warping. Questo passaggio garantisce improved flatness—critical for stamping or welding.
- Oil Coating: Un sottile strato di rust preventive oil (per esempio., mineral oil or eco-friendly ECO oil) is applied via spraying or rolling. The oil creates a barrier against moisture, keeping the steel rust-free for 3–6 months in storage.
- Edge Trimming (Opzionale): For sheets or strips, edges are trimmed to remove irregularities and ensure consistent width.
Per Suggerimento: Hydrochloric acid is better for automotive-grade PO steel (needs ultra-smooth surfaces), while sulfuric acid is more cost-effective for construction parts.
3. Qualità della superficie & Proprietà: Why PO Steel Outperforms Hot-Rolled
PO steel’s unique properties solve common problems with hot-rolled steel (like scale or rust). Here are its most valuable traits:
- Scale-Free Surface: Pickling removes all oxide scale, so there’s no need for grinding or sandblasting before painting/welding. This saves 20–30% on prep time.
- Improved Flatness: Tension leveling eliminates warping—PO steel sheets lie flat, making assembly easier (per esempio., for storage tanks).
- Uniform Oil Film Thickness: The oil coating is 5–10 μm thick (consistent across the surface), so no area is unprotected from rust.
- Enhanced Paint Adhesion: The clean, slightly porous surface (from pickling) lets paint bond better. Tests show paint on PO steel lasts 2x longer than on untreated hot-rolled steel.
- Reduced Oxide Pitting: Acid pickling removes deep scale, preventing pitting that can weaken parts (critical for pressure vessels).
Data Comparison: PO Steel vs. Untreated Hot-Rolled Steel
| Proprietà | Pickled and Oiled Steel | Untreated Hot-Rolled Steel |
|---|---|---|
| Surface Condition | Scale-free, liscio | Rust-prone, scaly |
| Paint Adhesion | Eccellente | Povero (necessita di levigatura) |
| Storage Rust Resistance | 3–6 mesi | 1–2 settimane (without oil) |
4. Applicazioni & End-Use Industries: Where PO Steel Shines
PO steel’s versatility makes it a staple in industries needing clean, easy-to-work metal. Here are its top uses:
- Automobilistico: Componenti del telaio automobilistico (Acciaio PO) (per esempio., frame rails, bracci di controllo) rely on its flatness for precise welding and its scale-free surface for corrosion-resistant coatings.
- Pipe & Tube: Pipe and tube manufacturing (Acciaio PO) uses coils—its smooth surface ensures seamless welding, and the oil coating prevents rust during tube forming.
- Agricolo: Tractor bodies, plow blades, and harvester parts use PO steel sheets—its durability resists dirt and impact, and the oil coating protects it during outdoor storage.
- Stampaggio: Stamping and deep drawing (Acciaio PO) is ideal for complex shapes (per esempio., metal buckets, staffe automobilistiche)—its ductility and smooth surface prevent cracking during forming.
- Magazzinaggio & Pressure Vessels: Storage tanks and pressure vessels (Acciaio PO) need a scale-free surface to avoid weak points—pickling ensures the steel can handle high pressure without leaking.
5. Gradi, Standard & Specifiche: Ensuring Quality
Using certified PO steel avoids defects and ensures compliance with industry rules. Here are the key standards and grades to know:
| Standard/Grade | Origin | Key Characteristics | Usi comuni |
|---|---|---|---|
| ASTM A1011 | U.S.A. | Covers hot-rolled PO steel for general use | Travi da costruzione, storage tanks |
| SAE 1008/1010 Acciaio PO | U.S.A. | Low-carbon, elevata duttilità | Stamped parts, assetto automobilistico |
| JIS G3131 SPHC-PO steel | Giappone | Commercial quality, buona formabilità | Involucri elettrici, piccole parentesi |
| IN 10111 DD11 pickled and oiled | Europa | Low-carbon, suitable for bending | Raccordi per tubi, agricultural parts |
| Structural grade A36 PO steel | U.S.A. | Alta resistenza (250 MPa yield), durevole | Heavy machinery frames, construction columns |
Certification Tip: Always request a Mill Test Report (MTR) to confirm the steel meets your grade—this document verifies pickling process, oil type, e qualità della superficie.
6. Rivestimenti & Post-Treatments: Extending PO Steel’s Lifespan
PO steel can be further treated to boost rust resistance, improve paint adhesion, or fit specific project needs. Here are the most common options:
- Oiled vs. Dry Pickled Steel: Oiled PO steel has rust protection for storage; dry pickled steel (no oil) is better for projects where oil could contaminate processes (per esempio., food-grade tanks).
- Pre-Primed Pickled and Oiled Steel: A factory-applied primer is added to the oiled surface—saves time on-site, as the steel is ready to paint.
- Thin Organic Coating: A polymer layer (per esempio., epossidico) is applied over the oil—ideal for outdoor parts (per esempio., construction framing) that need long-term rust resistance.
- Rust-Preventive Oil Types: Mineral oil is cost-effective for indoor storage; ECO oil is biodegradable (better for environmentally sensitive projects, like marine equipment).
- Wax-Coated Pickled and Oiled Steel: A thick wax layer provides 12+ months of rust protection—used for long-term storage or shipping to humid regions.
La prospettiva della tecnologia Yigu
Alla tecnologia Yigu, consigliamopickled and oiled steel for clients needing efficient, low-waste manufacturing. For automotive projects, we supply SAE 1008/1010 PO steel—its ductility ensures smooth stamping, and our hydrochloric pickling process delivers a paint-ready surface. For construction clients, we offer A36 PO steel with ECO oil, allinearsi agli obiettivi di sostenibilità. We also provide custom-slit coils to match project widths, reducing material waste by up to 10%.
Domande frequenti
- Do I need to remove the oil from PO steel before welding?
Yes—oil can burn during welding, creating porous welds. Wipe the surface with a degreaser (per esempio., acetone) before welding to ensure strong joints. - How long does the oil coating on PO steel last?
Standard rust preventive oil lasts 3–6 months in indoor storage. For outdoor or humid conditions, choose wax-coated PO steel (12+ mesi) or zinc-plate it for permanent protection. - Can PO steel be used for food-grade applications?
Yes—but use dry pickled steel (no oil) and ensure it meets food-safe standards (per esempio., ASTM A240 for stainless steel PO variants). The scale-free surface prevents bacteria buildup.