S355NL vs S355ML EN 10025-4 Low Temp Plate Supplier

 

S355NL vs S355ML EN 10025-4 Low Temp Plate Supplier

Gangsteel – China's Leading Mill-Direct Supplier & Exporter of S355NL and S355ML Low Temperature Steel Plates

Gangsteel is your trusted source for both S355NL normalized plates and S355ML TMCP low temp plates under EN 10025 standards. We stock over 6,000 tons combined, thickness 6–200 mm, width 1500–4200 mm, length up to 18 m, with immediate availability for global projects. All plates come from approved mills (HBIS, Shougang) with EN 10204-3.1/3.2 certificates, PED/CE compliance, and third-party inspections (DNV, ABS, LR, BV, CCS, KR, TÜV, SGS).

S355NL (EN 10025-3) and S355ML (EN 10025-4) are both excellent low-temp structural steels with 355 MPa yield and –50 °C toughness, but differ in delivery method: normalized vs. thermomechanical. This comparison helps engineers choose based on weldability, cost, and application. Gangsteel offers both with Z25/Z35, UT S2/E2, and processing services. Explore our en 10025 4 High Strength Structural Steel range for more options.

 

S355NL vs S355ML – Key Differences in Delivery and Performance

S355NL and S355ML are nearly identical in strength and toughness but differ fundamentally in processing: S355NL is normalized (N) per EN 10025-3, while S355ML is thermomechanically rolled (M) per EN 10025-4. Both guarantee 355 MPa yield, 470-630 MPa tensile, and ≥27 J at –50 °C, making them suitable for cold-service structures like offshore platforms or alpine bridges.

Core Similarities:

• Yield/tensile strength identical across thicknesses
• Low-temp impact (KV ≥27 J long. at –50 °C)
• CEV ≤0.39 for weldability (no preheat to 80 mm)
• Fine-grain structure for ductility (A5 ≥22%)

Main Differences:

• Delivery State: S355NL requires separate normalizing heat treatment (850-900 °C + air cool), adding cost/time. S355ML achieves properties via TMCP during rolling (controlled deformation + accelerated cooling), saving 10-15% on processing.
• Weldability & HAZ: TMCP S355ML has lower residual stresses and finer HAZ grains, reducing distortion by 20-30% vs. normalized S355NL.
• Cost: S355NL ~10-20% cheaper upfront but higher fab costs; S355ML premium offset by efficiency.
• Applications: S355NL for shop-welded (less field work); S355ML for site-welded offshore/cold fields.

S355ML dominates modern projects (60% market share per Eurofer) due to TMCP advantages. For grade meaning, see S355ML Meaning EN 10025-4 Structural Steel Supplier.

 

Chemical Composition – Ladle and Product Analysis

Both grades share identical chemistry for consistent performance.

Ladle Analysis (max % unless noted)

Element	C	Si	Mn	P	S	Nb	V	Al min	Ti	Cr	Ni	Mo	Cu	N	CEV max
S355NL/ML	0.18	0.50	1.60	0.035	0.030	0.05	0.12	0.020	0.05	0.30	0.50	0.10	0.55	0.015	0.41

Product Analysis (deviations per EN 10025-1 Table 4)

Element	C	Si	Mn	P	S	Nb	V	Al total	Ti	Cr	Ni	Mo	Cu	N
Deviation	+0.02	+0.05	+0.10	+0.010	+0.010	+0.01	+0.02	+0.030	+0.03	+0.05	+0.05	+0.03	+0.03	+0.003

Actual Gangsteel values: C 0.10-0.14%, CEV 0.35-0.38. Nb/V refine grains. Full: S355ML Chemical Composition EN 10025-4 Supplier.

 

Mechanical Properties – Full Thickness Range up to 200 mm (Transverse)

Identical specs; S355NL has slight HAZ edge from normalizing, but TMCP S355ML better isotropy.

Thickness (mm)	ReH min (MPa)	Rm (MPa)	A5 min (%)	KV min (J, long. –50 °C)
≤16	355	470–630	22	27
16<t≤40	345	470–630	22	27
40<t≤63	335	470–630	22	27
63<t≤80	325	470–630	22	27
80<t≤100	315	470–630	22	27
100<t≤120	305	450–610	22	27
120<t≤150	295	450–610	22	27
150<t≤200	285–295*	450–610	22	27

*Mill agreement for >150 mm; Gangsteel 295 MPa to 180 mm. Hardness 140-180 HBW; density 7.85 g/cm³. Details: S355ML Mechanical Properties EN 10025-4 Plate Supplier.

 

Equivalent International Grades

Both equivalents similar; S355ML TMCP preferred for weld.

Standard	S355NL Equiv	S355ML Equiv	Notes	Scenario
ASTM	A633 Gr.C	A572 Gr.50 + Z35	NL normalized; ML TMCP	US cold bridges
JIS	SM490A	SM490AW	Weathering opt	Japanese marine
GB/T	Q345E	Q345E	Low-temp match	China-EU
API 2W	Gr.50	Gr.50	ML LT better	Offshore

Indicative. Full: S355ML Equivalent Material EN 10025-4 Plate Supplier.

 

Applications & Design Considerations

Both for low-temp (–50 °C), S355ML for field-welded, S355NL shop.

• Offshore: S355ML jackets (TMCP low stress); S355NL decks (normalized stable).
• Cold Bridges: S355ML girders (weld ease); S355NL piers (shop fab).
• Pipes: S355ML penstocks (thin, TMCP); S355NL headers (thick, normalized).

Design: Eurocode 3; S355ML 20% less distortion. Z35 for tension. Eco: TMCP 15% less energy. Gangsteel V-bevel, UT S3.

 

Why Choose Gangsteel for S355NL & S355ML

• 6,000+ t stock both grades.
• Mill-direct 50-100 USD/t save.
• Processing: laser ±0.5 mm, X-bevel, 150 mm drill, 600 mm roll, C5 200 µm.
• Cert: ISO 9001, NACE, EN 1090 EXC4.
• Legacy: Siemens 1,000+ t (Hornsea), Total (Ichthys)—OTIF 100%.

To 90+ countries: Rotterdam 7 days.

 

FAQ

Q1: S355NL vs S355ML difference?

A: Delivery: NL normalized (separate heat treat), ML TMCP (rolling process). ML lower stress, better weld; NL stable for shop. Both same strength/-50 °C KV.

Q2: Which for offshore?

A: S355ML preferred (TMCP field-weld ease); NL for shop-heavy. Both DNV-OS-B101.

Q3: Preheating?

A: No to 80 mm (CEV 0.35-0.38); 80-120 °C thicker. ML 20% less distortion.

Q4: Price?

A: NL +10-20 USD/t cheaper; ML efficiency offsets. FOB 680-780 USD/t (25 mm).

Q5: Z35?

A: Stock for both (≥35% RA EN 10164 Cl.3); Norsok compliant.

Q6: Equiv ASTM?

A: Both A633 Gr.C; ML + TMCP for HAZ. Dual-cert.

Q7: Lead time?

A: Stock 2-4 days; processed 3-6 days; mill 4 weeks.

 

Contact Gangsteel

For S355NL/ML low temp plates, quote now.

Email: admin@gangsteel.com WhatsApp/WeChat/Mobile: +86 135 9887 9167 Website: https://gangsteel.net/

Gangsteel—Low Temp Leadership. Stocked for cold success.

 

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