S355 HSLA Steel Plate

What is S355 HSLA Steel Plate?

S355 HSLA Steel Plate is a high-strength low-alloy (HSLA) structural steel plate that complies with the European standard EN 10025 series (mainly EN 10025-2, EN 10025-3, EN 10025-4), widely recognized as one of the most versatile and cost-effective structural steels in the global market.

 

As a professional S355 HSLA steel plate supplier, GNEE STEEL provides high-quality S355 HSLA steel plates with stable performance, complete specifications, and reliable quality, fully meeting the strict requirements of various engineering projects worldwide.

 

The "S" in S355 stands for structural steel, and "355" indicates the minimum yield strength of 355 MPa for plates with thickness ≤16mm, which is significantly higher than ordinary carbon structural steel (such as S235).

 

S355 HSLA steel plate is a micro-alloyed steel with low carbon content, adding a small amount of alloying elements (such as niobium, vanadium, titanium) to achieve excellent comprehensive performance without sacrificing weldability and formability. It is available in multiple quality grades (JR, J0, J2, K2, N, NL, MC, etc.), each with different low-temperature impact toughness requirements to adapt to diverse working environments, making it the mainstream choice for modern structural engineering.

 

 

The chemical composition of S355 HSLA Steel Plate is strictly controlled to balance strength, toughness, and weldability.

 

The following table shows the maximum heat analysis values of chemical elements (in %) in line with EN 10025 series standards, which is crucial for the performance of S355 HSLA steel plate (taking common grades S355JR, S355J0, S355J2 as examples):

Steel Grade	Thickness (mm)	C (Max)	Si (Max)	Mn (Max)	P (Max)	S (Max)	N (Max)	Cu (Max)	Nb (Max)	V (Max)	Ti (Max)
S355JR	≤16	0.24	0.55	1.60	0.035	0.035	0.012	0.55	0.05	0.10	0.05
	16-40	0.24	0.55	1.60	0.035	0.035	0.012	0.55	0.05	0.10	0.05
	>40	0.24	0.55	1.60	0.035	0.035	0.012	0.55	0.05	0.10	0.05
S355J0	≤16	0.20	0.55	1.60	0.030	0.030	0.012	0.55	0.05	0.10	0.05
	16-40	0.20	0.55	1.60	0.030	0.030	0.012	0.55	0.05	0.10	0.05
	>40	0.22	0.55	1.60	0.030	0.030	0.012	0.55	0.05	0.10	0.05
S355J2	≤16	0.20	0.55	1.60	0.025	0.025	0.012	0.55	0.05	0.10	0.05
	16-40	0.20	0.55	1.60	0.025	0.025	0.012	0.55	0.05	0.10	0.05
	>40	0.22	0.55	1.60	0.025	0.025	0.012	0.55	0.05	0.10	0.05

 

 

Steel Grade	Thickness (mm)	Yield Strength (ReH, ≥MPa)	Tensile Strength (Rm, MPa)	Elongation (A, ≥%)	Impact Temperature (°C)	Impact Energy (KV, ≥J)	Delivery Condition
S355JR	≤16	355	470-630	21	20 (Room Temperature)	27	Hot Rolled (AR)
	16-40	345	470-630	21	20 (Room Temperature)	27	Hot Rolled (AR)
	>40	335	470-630	21	20 (Room Temperature)	27	Normalized (N)
S355J0	≤16	355	470-630	21	0	27	Normalized (N)
	16-40	345	470-630	21	0	27	Normalized (N)
	>40	335	470-630	21	0	27	Normalized (N)
S355J2	≤16	355	470-630	21	-20	27	Normalized (N) / Thermo-Mechanically Rolled (M)
	16-40	345	470-630	21	-20	27	Normalized (N) / Thermo-Mechanically Rolled (M)
	>40	335	470-630	21	-20	27	Normalized (N) / Thermo-Mechanically Rolled (M)

 

 

Plate thickness	8–200 mm (dependent on steel grade; up to 300 mm upon request)
Plate width	3,950 mm max. (dependent on thickness and steel grade)
Plate length	18,700 mm max. (dependent on thickness and steel grade; up to 24,000 mm available upon request)
Ordered weight	At least 20 tons per line item
Unit weight	20.5 tons max. per single plate (dependent on steel grade)

 

 

As a high-performance S355 HSLA steel plate, it has significant advantages over ordinary carbon structural steel, making it the first choice for various engineering projects. GNEE STEEL's S355 HSLA products further highlight these advantages through strict quality control:

 

Excellent Strength-to-Weight Ratio: With a minimum yield strength of 355 MPa, it is 30% higher than S235 steel, allowing the use of thinner sections to reduce structural weight while ensuring load-bearing capacity, reducing material consumption by 8%-15% compared to ordinary steel.

 

Superior Comprehensive Toughness: Different grades (JR/J0/J2) adapt to different temperature environments, from room temperature to -20°C, with stable impact toughness, avoiding brittle fracture in low-temperature or harsh working conditions, which is crucial for outdoor and alpine projects.

 

Outstanding Weldability: Low carbon equivalent and optimized chemical composition make it easy to weld (arc welding, gas welding, etc.) without preheating (or low preheating temperature), facilitating on-site assembly and complex structural fabrication, improving construction efficiency.

 

Cost-Effective & High Value: As a cost-effective HSLA steel, it balances high performance and low cost, eliminating the need for expensive alloy materials while meeting high-load requirements, reducing overall project costs (material, transportation, installation).

 

Good Formability & Processability: It can be easily cut, bent, punched, and machined, adapting to various processing needs of structural parts, suitable for customized production of complex components in machinery and construction fields.

 

Strict Quality Compliance: Fully complies with EN 10025 series standards, with optional ultrasonic flaw detection (EN 10160, ASTM A435) and mill test certificate (EN 10204 3.1/3.2), ensuring product reliability and compliance with international project requirements.

 

Wide Environmental Adaptability: It has good corrosion resistance and fatigue resistance, suitable for outdoor, marine, and industrial environments, and can be further processed (galvanized, painted) to enhance corrosion resistance.

 

 

Due to their excellent comprehensive performance, S355 HSLA steel plates are widely used in various structural engineering fields, covering construction, machinery, transportation, energy, and other industries. GNEE STEEL provides customized specifications to meet the needs of different projects:

 

Construction & Bridge Engineering: High-rise building frames, long-span bridges, bridge supports, steel structures for industrial plants, and residential buildings. S355J2 is especially suitable for outdoor and cold-region projects (such as northern Europe, northern China) due to its low-temperature toughness.

 

Heavy Machinery & Equipment: Crane booms, excavator structures, loaders, mining equipment, and engineering machinery parts. Its high strength and formability ensure the durability of heavy-load equipment in harsh working conditions.

 

Transportation & Marine Engineering: Ship hulls, ship decks, container frames, railway carriages, and highway guardrails. S355 HSLA steel's corrosion resistance and toughness adapt to marine and long-distance transportation environments.

 

Energy & Power Engineering: Wind power towers, power plant structural components, boiler supports, and oil and gas pipelines. It meets the high-load and outdoor harsh environment requirements of energy projects, ensuring long-term stable operation.

 

Other Fields: Storage tanks, pressure vessels, hydraulic structures, and light steel structures. Its versatility and cost-effectiveness make it suitable for various low-to-medium load structural scenarios, becoming the mainstream material in modern structural engineering.

 

 

S355 HSLA Steel Plate has corresponding equivalent grades in different international standards, which is convenient for customers in different regions to select and use. As a professional S355 HSLA supplier, GNEE STEEL can provide products that meet various standard requirements.

 

The equivalent grades of common S355 grades are as follows:

Our Grade (EN 10025 Series)	Material Number	Chinese Standard (GB/T 1591)	American Standard (ASTM)	Japanese Standard (JIS)	German Standard (DIN)
S355JR	1.0045	Q345B	A572 Gr.50	SS490B	St52-3
S355J0	1.0553	Q345C	A572 Gr.50 (Modified)	SS490C	St52-3J0
S355J2	1.0577	Q345D	A572 Gr.50 (Enhanced)	SS490D	St52-3J2

 

 

What is S355JR steel?

S355JR is a grade of low-carbon steel commonly used in structural applications. It is part of the 'S' family of steels, which includes S235, S275, and S355 grades. The "JR" designation means that the material has been subjected to a Charpy V-notch impact test at 208℃ and has a minimum impact strength of 27 Joules.

 

What is equivalent to S355JR?

In other countries, there are also similar steel materials or called S355JR equivalent grades. They are Q345B-China material, A572 Gr 50-America material, ST52-3-Germany material, SM490B-Japanese material, etc.

 

What is the difference between S355JR and S355J2 N?

S355JR steel has a minimum impact strength of 27 J under 20-degree temperature conditions while the second type of steel, S355J2+N has the same impact strength but with a temperature of -20 degrees.

 

What is the difference between mild steel and S355JR?

Compared with mild steel grades, S355 structural steel provides higher yield strength and improved load-bearing capacity, which is why it is widely used in heavy structural engineering.

 

Is S355jo better than S355JR?

While both S355JR and S355J0 are structural steels with similar chemical compositions, the key difference lies in their impact requirements and usage scenarios. S355J0 possesses slightly stronger mechanical properties, making it suitable for applications requiring higher strength.

 

What is the meaning of J2, Jr., and J0 in S355 material?

In S355 material (according to the EN 10025 series, specifically EN 10025-2 for hot-rolled products), the suffixes J2, JR, and J0 indicate the impact toughness (notch toughness) of the steel at a specified temperature

 

 

What is equivalent to S355JR steel?

A572Gr50 steel plate and S355JR steel plate both are high strength low alloy steel materials with minimum yield strength at 345Mpa and 355Mpa.So S355JR steel plate is equivalent to A572Gr50 steel plate.

 

What is the difference between S355JR and S355J2?

Simply put, the S355J2 steel adapts better to low-temperature work conditions than the S355JR steel does. Alloy steel manufacture of S355J2 products include semi-finished products, and various flat and long products. The steel has very good weldability whether you use heat or not.

 

What is the US equivalent of S355J2?

A572 Grade 50

The ASTM equivalent of S355J2 is A572 Grade 50, with similar high strength and low-temperature toughness for structural use. Gnee steel's high-quality plates ensure compliance for your projects. For more, explore our BS EN 10025-2 material grade guide.

 

What is S355J2 equivalent material in China?

EN10025 S355J2 is low alloy steel commonly used in Europe. EN10025 S355J2 equivalent grade in China is Q345D. Their chemical composition is slightly different and mechanical properties are similar.

 

 

S355 HSLA Steel Plate is a high-performance, cost-effective high-strength low-alloy structural steel that complies with EN 10025 series standards, with excellent strength, toughness, weldability, and formability. Its multiple quality grades (JR/J0/J2) adapt to diverse temperature environments and project requirements, making it the mainstream material for modern structural engineering, widely used in construction, machinery, transportation, energy, and other fields.

 

GNEE STEEL is committed to providing high-quality S355 HSLA steel plates and professional one-stop services, from product selection to after-sales support, to help you reduce costs, improve efficiency, and ensure project safety.

 

Whether you need standard specifications or customized solutions, we can meet your needs with our strength and experience. With S355 HSLA steel plate from GNEE STEEL, you can get reliable material support for your project and achieve win-win cooperation.

Get Your Customized S355 HSLA Steel Plate Quote Now!

 

Are you looking for high-quality, cost-effective S355 HSLA steel plates for your project? Do you need professional technical guidance to choose the right grade and specifications? Contact GNEE STEEL now to get a free quote and detailed product sample!

 

📩 Send us an inquiry with your requirements (grade, thickness, width, length, quantity, and project scenario), and our professional team will reply to you within 2 hours, providing customized solutions and the most competitive price.

 

 

 

 

 

 

 

 

Our products have undergone strict quality testing and come with professional certificates. If you have any questions about (HSLA) Alloy Steel Plate, please feel free to inspect.

 

Relying on many first-class equipment, such as CNC Shearing machine, Press Brake machine, Straightening machine, Roll Bending machine, Flat Bar Machine, Deburring machine etc, GNEE STEEL could provide various semi-productsand extensive forming services to customers.

 

GNEE STEEL  PROCESSING

1.CTL & SL SERVICE (141 SETS)

Currently, GNEE STEEL has imported manyadvanced CTL/SL equipment from Italy and Korea and could provide customized CTL/SL services from cold rolled stainless steel and carbon steel to hot rolled stainless steel and carbon steel as well as strips and ultra-wide sheet.

CTL FACILITIES
Max Length:16500mm

Max Width:2200mm

Max Thickness:25.4mm

Max Yield Strength:1500Mpa
SL FACILITIES

Max Width:2200mm

Max Thickness:18mm

Max slit Quantity:31

Max Yield Strength:1200Mpa

 

2.CUTTING SERVICE

GNEE STEEL imported lots of advanced cutting machines from Germany, Sweden, America and Japan, including plasmas cutting machine, water jet cutting machine, laser cutting machine, flame cutting machine and saw machine. In order to meet customers' diversified needs, GNEE STEEL also adopts nest working multi-cutting methods and intensive production to improve production capacity and save costs for the customers.

Laser Cutting Machine

Max Cutting Length:40,000mm

Max Width:4,600mm
Max Thickness:100mm

 

Flame Cutting Machine

Max Cutting Length:40,000mm

Max Width:8,000mm
Max Thickness:500mm

Plasmas Cutting Machine

Max Cutting Length:30,000mm

Max Width:5,000mm
Max Thickness:100mm

 

Water-jet Cutting

Max Cutting Length:12,000mm

Max Width:4,010mm
Max Thickness:250mm

3.FORMING SERVICE

Steel Plate Roll Bending
Maximum Rolling Thickness: up to 200mm
Maximum Width: 4200mm

   

Automatic Bending Machine-Press Brake
Max Bending Capability:3000Ton
Max Bending Length:15,000mm

Expert in Bending High-Strength & Wear-Resistant Steels

  

  

Punching Machine

Max Width:3,070mm
Max Thickness:8mm

Max Pressure:250t

BEVELING SERVICE

GNEE STEEL beveling platform has edge milling machine, edge planer, flame / plasma groove cutting machine, flame groove cutting robot, desktop chamfering machine, gantry planerand other advanced equipment to provide customers with parts prefabrication services,daily processing of V-type, Y-type, X-type and U-type grooves, and guarantee subsequent processes such as welding and assembly of products.

 

Milling：
Max Cutting Length:18,000mm

Max Width:4500mm
Max Thickness:120mm

 

  

Beveling:
Max Length:16,000mm

Max Thickness:80mm

MACHINING SERVICE

GNEE STEEL owns CNC Portal-type Boring and Milling machine,CNC Floor-type Boring and Milling machine, Vertical Precision 5-axis Milling Machine, Portal-type Planer, Vertical Lathe, Cylindical Grinding machine, Hydraulic Planer and CNC Lathe and could provide fine machining of large spare parts and structural parts for customers.

Gantry Type Boring & Milling Maching Center

Max Length:48000mm

Max Width:12500mm
Max Height:8000mm

Max Diameter:10500mm

Deep-hole Drilling Equipment
Max Driling Depth:1,100mm
Max Bore Diameter:φ80mm
Max Diametar:φ4,500mm

MMulti-hole Drilling Equipment

Max Length:13,000mm
Max Width:10,000mm
Max Bore Diameter:φ105mm
Max Drilling Depth:250mm

Floor Boring And Milling Machine
Max Length:24,000mm
Max Height:8,000mm
Turntable Dimensions:9x5m

Vertical Lathe

Max Height:6,000mm

Max Diametar:φ22,00mm

Automated Edge Milling Machine

The Automated Edge Milling Machine is a leading product in heavy-duty milling equipment. It is primarily used for weld groove preparation (beveling) on large-format plates made of stainless steel, carbon steel, and special steel grades. It can process plates with a maximum thickness of up to 90mm, a length of 16 meters, and a width of 4 meters.

 

It is equipped with dual milling units and a fully automatic milling cutter head changing system, enabling automated 4-edge beveling. Its standout feature is the profiling technology used when milling wavy plates and irregularly shaped products, which ensures absolute consistency of the groove after milling.

 

Utilizing specially designed milling cutter heads, it can execute highly difficult and complex groove profiles in a single pass.

 

Materials: Plain carbon steel, pressure vessel steel, wear-resistant steel, high-strength steel, stainless steel, nickel-based alloys, etc.
Width: 1200 - 4200 mm
Length: 5800 - 16000 mm
Thickness: 5 - 90 mm
Weight: Up to 35 tons

 

This edge milling machine is the world's premier automated bevel milling equipment. With its excellent structural design and advanced data algorithms, it achieves full automation from plate detection to the actual milling process, significantly improving processing efficiency while guaranteeing high precision.

 

• Processing Accuracy

Length accuracy: ±1mm when L < 10m; ±2mm when L > 10m;

Width accuracy: ±1mm;

Diagonal accuracy: ±2mm;

Root face accuracy (blunt edge): ±1mm for Y-grooves; +0.5mm for X-grooves.

• Processing Efficiency

The processing efficiency is more than 10 times that of conventional edge milling or edge planing equipment.

HEAT TREATMENT

Heat Treatment Furnace
Max Furnace Size:36x12x13.5m
Max Rated Temperature:1100℃
Max Loading Capacity:800t

Heat Treatment of Pressure Vessels
Heat Treatment of Mining Equipment
Heat Treatment of Tube Sheet
Heat Treatment of Pressure Vessel Head

 

 

GNEE STEEL is currently participating in the procurement phase of a 100,000m³ full containment ammonia storage tank project, supplying high-quality steel plates for critical tank components. Due to the corrosive nature of ammonia and the risk of Ammonia Stress Corrosion Cracking (SCC), the project requires strict metallurgical control of materials according to EN 10028-3 standards.

 

One of the most important technical requirements of this project is the strict limitation of the actual Yield Strength (Re) for all NL2 grade materials. To prevent SCC risks in ammonia storage environments, the actual yield strength must not exceed 390 MPa, regardless of the nominal values specified in the standard or plate thickness ranges. This requirement places higher demands on steelmaking process control, heat treatment stability, and material testing.

 

Raw high-strength steel plates ready for the 100,000 m³ full containment ammonia storage tank production

 

Project Materials and Technical Requirements

 

The project mainly uses P355NL2 and P275NL2 normalized pressure vessel steel plates, which are widely applied in low-temperature storage tanks due to their excellent toughness and weldability.

 

Key technical specifications include:

• Material grades: P355NL2 and P275NL2 (Normalized)
• Yield strength: Standard minimum / Maximum limited to 390 MPa
• Hardness: ≤ 225 HBW in base material
• Impact testing: Charpy-V notch test at -50°C, minimum 27J
• Certification: EN 10204 3.1 certificate, with optional 3.2 certification

 

These strict requirements ensure that the steel plates maintain stable mechanical properties and high resistance to ammonia-induced stress corrosion during long-term operation.

 

Precision rolling and forming of steel plates into curved sections for the 100,000 m³ ammonia storage tank.

 

Project Plate Quantities and Thickness Distribution

 

The total steel demand for this ammonia storage tank project is several thousand tons, mainly distributed across different tank sections:

 

P355NL2 – Inner & Outer Tank Shell Plates

• Lower shell courses: 50 mm thickness – approx. 2,000 tons
• Middle shell courses: 25 mm thickness – approx. 1,400 tons
• Upper shell courses: 10 mm thickness – approx. 500 tons

 

P275NL2 – Tank Bottom Plates

• Thickness: 10–15 mm – approx. 750 tons

 

P275NL2 – Suspended Roof Structure

• Thickness: 5–8 mm – approx. 180 tons

 

S275JR – Outer Roof (Ambient Structure)

• Thickness: 10 mm – approx. 450 tons

 

To improve tank fabrication efficiency and reduce circumferential welds, the project also requires wide steel plates to minimize welding joints, which helps reduce the potential risk of SCC in ammonia service conditions.

 

Formed steel segments wrapped and racked for protection, ready for 100,000 m³ ammonia storage tank assembly.

 

GNEE STEEL provides high-precision steel plate rolling and cylinder fabrication solutions for tank manufacturers worldwide. Send us your plate specifications or fabrication drawings for a fast quotation.

Request A Quote

 

TYPE	GRADE	SPECIFICATIONS
Carbon Steel / Low Alloy Coil	Q235A/B/C/D/Q355B(Q345B)/C/D/E/SS400/SAPH400-C/ASTMA283Grade C	0.7~2.0*1250/1500mm*C 2.3~19.5*1250/1500/1800/2000mm*C
Medium Heavy Plate	Q235B/Q355B(Q345B)/C/D/E	6.0-200x150mm-4000mmxL
Vessel Plate	Q245R/Q345R/HP295/SA516MGR485/SA516GR70/P355NL2/P275NL2/ S275JR//SPV490/ASTM A537 Class 1/Class 2	2.5-120x1500mm-3000mmxL
High Strength Steel	510L/610L/700L/750L/BS600MCK4/BS700MCK2/BS700MCK4/ BS960E/BWELDY700QL2/L4/BWELDY960QL4/HG60D/70D/785D/ Q460D/Q550D/690D/690E/TQ600MCD/TQ700MCD/S700MCD/ WYS600/700/STRENX700MCE/Q490E/Q490D	1.2-60x 1500mm-2500mmxL
Patterned Steel	HQ235A|B	1.2-60x 1500mm-2500mmxL
Wear-resistance Steel	NM360/400/450/500/NM300TP/400TP/450TP/ ABREX400/450/500/B-HARD450XKY/ CREUSABRO4800/8000/EH C400LE/450LE/500LE/ HADOX450/500	3.0-50x1250mm-3300mmxL
Cold Rolled Coil	DC01/RECC/REDT/SPCC/ST12	0.5-3.0x1250mm-1500mmxC
Galvanized Plate	DC51D+AZ/DC51D+Z/DX51D+Z/SGH340+Z275/Z275/Z120/S350GD+ZM275	0.45-3.0x1250mm-1500mmxC
Pickled Coil	DD11/SPHC	2.0-6.0x1500xC

Stainless Steel Material and Surface Specifications

TYPE	GRADE	THICKNESS	SURFACE
Austenitic	304/304H/304L/304J1	0.25-150mm	2B/BA/NO.4/8K/SB/HL/NO.1
Austenitic	321	0.4-80mm	2B/BA/NO.4/8K/SB/HL/NO.1
Austenitic	316/316L/317L/316Ti	0.3-80mm	2B/BA/NO.4/8K/SB/HL/NO.1
Austenitic	201(J1/J2/J5)	0.35-12mm	2B/NO.1/1D
Ferrite	430	0.4-3.0mm	2B/BA/NO.4/8K/SB/HL
Ultra Pure Ferrite	443	0.4-2.0mm	2B
Ultra Pure Ferrite	436L/439/444/441	0.5-3.0mm	2B/2D

Special Steel / Nickel Base Alloy

TYPE	GRADE	GRADE (ASTM)	GRADE (EN)	THICKNESS
Heat-resistant Steel	309S	S30908	1.4833	0.5-40mm
Heat-resistant Steel	310S	S31008	1.4845	0.5-40mm
Duplex Stainless Steel	2101	S32101	1.4162	1.5-50mm
Duplex Stainless Steel	2304	S32304	1.4362	3.0-50mm
Duplex Stainless Steel	2205	S32205/S31803	1.4462	0.5-60mm
Duplex Stainless Steel	2507	S32750	1.4410	1.0-60mm
Super Austenitic-Steel	904L	N08904	1.4539	0.6-50mm
Super Austenitic-Steel	254SMO	S31254	1.4547	0.5-50mm
Super Austenitic-Steel	1.4529	N08926	1.4529	0.5-50mm
Super Austenitic-Steel	AL-6XN	N08367	1.4478	0.5-50mm
Nickel Base Alloy	Alloy 31	N08031	1.4562	1.0-50mm
Nickel Base Alloy	800	N08800	1.4876	0.8-50mm
Nickel Base Alloy	800H	N08810	1.4958	0.8-50mm
Nickel Base Alloy	800HT	N08811	1.4959	0.8-50mm
Nickel Base Alloy	Alloy 28	N08028	1.4563	1.0-20mm
Nickel Base Alloy	Alloy 20	N08020	2.4660	1.0-20mm
Nickel Base Alloy	825	N08825	2.4858	0.8-40mm
Nickel Base Alloy	C276	N10276	2.4819	0.5-50mm
Nickel Base Alloy	C22	N06022	2.4602	1.0-50mm
Nickel Base Alloy	625	N06625	2.4856	0.8-20mm
Nickel Base Alloy	400	N04400	2.4360	1.0-20mm
Nickel Base Alloy	600	N06600	2.4816	1.0-50mm
Nickel Base Alloy	Pure Ni 201	N02201	2.4061	0.5-20mm
Titanium	TA1	Gr.1	Class 1	0.5-50mm
Titanium	TA2	Gr.2	Class 2	0.5-50mm

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