What 1.1106 steel is
1.1106 is the EN material number for steel grade P355NL2. It is a normalised weldable fine-grain steel used for pressure equipment that has to stay tough at low service temperature.
The designation itself sets out what the grade guarantees:
- P: steel for pressure purposes.
- 355: minimum yield strength of 355 MPa in the thinnest product thickness.
- N: supplied normalised, or normalised-formed.
- L2: the second and more demanding low-temperature class, with Charpy V-notch impact energy guaranteed at −50 °C.
The grade is defined in EN 10028-3 for flat products and in EN 10216-3 for seamless tubes. Fine-grain treatment and controlled niobium, titanium and vanadium content give the grade its mix of moderate strength, weldability and cold toughness. In older German practice the same steel appears as EStE 355 under DIN 17102.
1.1106 is a plate and tube grade by origin, so forgings in this chemistry are ordered against a customer or project specification that references EN 10028-3. Jiangyin Jiangnan Metal forges to the specification sent with the enquiry and certifies to EN 10204.
Chemical composition of 1.1106 (P355NL2)
Limits below are from EN 10028-3:2009. Values are ladle analysis, per cent by mass.
| Element | Symbol | Limit (%) |
|---|---|---|
| Carbon | C | max 0.18 |
| Silicon | Si | max 0.50 |
| Manganese | Mn | 1.10 – 1.70 |
| Nickel | Ni | max 0.50 |
| Phosphorus | P | max 0.020 |
| Sulphur | S | max 0.010 |
| Chromium | Cr | max 0.30 |
| Molybdenum | Mo | max 0.08 |
| Vanadium | V | max 0.10 |
| Nitrogen | N | max 0.012 |
| Niobium | Nb | max 0.05 |
| Titanium | Ti | max 0.03 |
| Aluminium | Al | max 0.02 |
| Copper | Cu | max 0.30 |
| Combined micro-alloying | Nb + Ti + V | < 0.12 |
Seamless tube to EN 10216-3:2014 carries further limits: Mn 0.90–1.70, S max 0.005, N max 0.02, Ti max 0.04. Aluminium in fine-grain steels is tied to the grain-refining treatment, so check the applicable limit against the edition of the standard named in your order.
Mechanical properties of 1.1106
Values are for the normalised (+N) condition and are read against nominal thickness. Yield strength drops as thickness increases, which matters on heavy forged sections.
| Nominal thickness (mm) | to 16 | 16–40 | 40–60 | 60–100 | 100–150 | 150–250 |
|---|---|---|---|---|---|---|
| ReH, min (MPa) | 355 | 345 | 335 | 315 | 305 | 295 |
| Nominal thickness (mm) | to 60 | 60–100 | 100–150 | 150–250 |
|---|---|---|---|---|
| Rm (MPa) | 490–630 | 470–610 | 460–600 | 450–590 |
| A, min elongation at fracture (%) | 22 | 21 (60–250 mm) | ||
Low-temperature toughness
The L2 class is why 1.1106 is specified over P355N or P355NL1. Charpy V-notch energy is guaranteed at −50 °C, so the grade covers cold-climate pressure service without moving up to a nickel steel.
| Test temperature | −50 °C | −40 °C | −20 °C | 0 °C | +20 °C |
|---|---|---|---|---|---|
| KV transverse (J) | 27 | 30–33 | 40–47 | 60 | 70 |
| KV longitudinal (J) | 40–42 | 45–50 | 55–70 | 75–90 | 85–100 |
Longitudinal values run higher than transverse. State the orientation you need on the enquiry: on forged rings and discs the test direction relative to grain flow changes the qualifying value.
Equivalent and comparable grades
No cross-reference is an exact substitution. Chemistry ranges, test temperatures and product standards differ between systems. Use the table as a starting point and qualify against the governing specification for the project.
| System | Designation | Notes |
|---|---|---|
| EN number | 1.1106 | The material number for P355NL2 |
| EN name | P355NL2 | EN 10028-3 (plate), EN 10216-3 (tube) |
| Germany, DIN 17102 | EStE 355 | Special low-temperature quality |
| Same family, EN | P355N (1.0562), P355NH (1.0565), P355NL1 (1.0566) | Same strength class, less severe impact requirement |
| USA, ASTM forgings | A350 LF2 | Comparable low-temperature carbon-steel forging grade |
| USA, ASTM plate | A537 Class 1 | Normalised low-temperature pressure-vessel plate |
| China, GB | 16MnDR | Low-temperature pressure-vessel plate |
Forged products supplied in 1.1106
Jiangyin Jiangnan Metal is an open-die forging factory, so 1.1106 goes out as near-net forged shapes rather than stock plate or bar. Typical items:
Rings and cylindrical parts
- Seamless rolled rings and forged rings
- Sleeves, bushes, bushings and hollow bars
- Forged pipe, tube, tubing, barrels and casings
- Cases, shells, cylinders, hubs and housings
Discs and flat parts
- Forged discs and disks
- Tubesheets, tube sheets and tube plates
- Blocks and forged round bars
Valve and pressure components
- Valve bodies, valve blocks and valve bonnets
- Valve stems, valve closures and valve seat rings
Flanges and nozzles
- Girth flanges and channel covers
- FVC-type self-reinforced nozzles
- Long welding neck nozzles and nozzle necks
- Cover flanges and forged shafts
Shell-and-tube heat exchangers are a common application, because one chemistry covers the tubesheet, the girth flange, the channel cover and the nozzles.
Open-die forging capability
Figures below are for the works at Zhouzhuang Town, Jiangyin City. Ring rolling and free forging have different limits, so confirm the range for your geometry at enquiry stage.
| Parameter | Range |
|---|---|
| Single-piece weight | 5 kg – 30 t |
| Rolled ring outside diameter | 200 – 5,000 mm |
| Ring height | up to 1,500 mm |
| Forged disc diameter | up to 3,000 mm |
| Shaft length | up to 12,000 mm |
| Delivery condition | as-forged, normalised, N+T, or Q+T |
| Machining | rough machined, semi-finished, or finish machined to drawing |
Heat treatment and delivery condition
1.1106 is a normalising grade. The tables above apply to the +N condition. Normalising develops the fine ferrite-pearlite structure that carries the low-temperature toughness.
- Normalising (+N): the standard delivery condition, and the condition the EN 10028-3 property tables are written against.
- Normalised and tempered (+NT): used where a customer specification calls for it on heavier sections.
- Stress relieving: applied after heavy machining or welding where dimensional stability matters.
Simulated post-weld heat treatment on the test coupon can be arranged. State the PWHT cycle on the enquiry so the coupon matches the fabricated condition.
Testing, certification and documentation
Every 1.1106 forging leaves the works with a material certificate traceable to the heat number.
- Chemical analysis, ladle and product analysis
- Tensile test at room temperature
- Charpy V-notch impact test at the specified temperature, down to −50 °C
- Hardness survey
- Ultrasonic testing to the acceptance class named in the order
- Magnetic particle or dye penetrant inspection on machined surfaces
- Dimensional report against the customer drawing
- EN 10204 3.1 certification as standard; 3.2 with third-party witness on request
Third-party inspection by TUV, SGS, BV, Lloyd's Register or a customer representative can be arranged at the works.
Where 1.1106 is used
- Pressure vessels and separators operating at low ambient or process temperatures
- Shell-and-tube heat exchangers, including tubesheets and channel covers
- Cold-climate oil and gas surface equipment
- LPG and process gas storage
- Boiler and power plant components
- Petrochemical piping components and valve bodies
How to order 1.1106 forgings
Include the following when you write to sales@steelforgepieces.com:
- Grade and governing standard, for example 1.1106 / P355NL2 to EN 10028-3.
- Drawing or rough dimensions, including whether the price should be for as-forged or machined.
- Quantity and required delivery date.
- Delivery condition and any heat treatment requirement.
- Impact test temperature and orientation, transverse or longitudinal.
- NDT requirement and acceptance class.
- Certification level and whether third-party inspection is required.
- Destination port for the freight quotation.
Questions and answers
What is 1.1106 steel?
1.1106 is the EN material number for P355NL2, a normalised weldable fine-grain steel for pressure purposes specified in EN 10028-3. It provides 355 MPa minimum yield strength in thin sections and guaranteed Charpy impact toughness at −50 °C. It is a standard choice for low-temperature pressure equipment.
What does the NL2 in P355NL2 mean?
N means the steel is supplied in the normalised condition. L2 is the second and more demanding low-temperature class in EN 10028-3, which requires Charpy V-notch impact energy to be verified at −50 °C. The L1 class only guarantees impact energy down to −40 °C.
What is the difference between P355NL1 and P355NL2?
Both share the same 355 MPa strength class and a very similar chemistry. The difference is the guaranteed impact test temperature. P355NL1 (1.0566) is qualified to −40 °C, while P355NL2 (1.1106) is qualified to −50 °C and carries tighter limits on phosphorus and sulphur.
What is the chemical composition of 1.1106?
To EN 10028-3:2009, by mass: carbon max 0.18%, silicon max 0.50%, manganese 1.10–1.70%, nickel max 0.50%, phosphorus max 0.020%, sulphur max 0.010%, chromium max 0.30%, molybdenum max 0.08%, vanadium max 0.10%, nitrogen max 0.012%, niobium max 0.05%, titanium max 0.03%, aluminium max 0.02%, copper max 0.30%, with niobium plus titanium plus vanadium below 0.12%.
What is the yield strength of 1.1106?
Minimum yield strength in the normalised condition is 355 MPa up to 16 mm thickness, falling with section size: 345 MPa for 16–40 mm, 335 MPa for 40–60 mm, 315 MPa for 60–100 mm, 305 MPa for 100–150 mm and 295 MPa for 150–250 mm.
How cold can 1.1106 be used?
The grade carries a guaranteed transverse Charpy V-notch impact energy of 27 J at −50 °C, which is the qualifying test for the L2 class. The permitted minimum design metal temperature for a given component still depends on the design code, the section thickness and the fabrication route.
Is 1.1106 weldable?
Yes. P355NL2 is a weldable fine-grain steel, and low carbon combined with controlled micro-alloying keeps the carbon equivalent moderate. Preheat, interpass temperature and any post-weld heat treatment should follow the fabrication code and the section thickness. Weld procedure qualification remains the fabricator's responsibility.
What is the ASTM equivalent of 1.1106?
There is no exact ASTM equivalent. For forgings the closest comparable grade is ASTM A350 LF2, a low-temperature carbon-steel forging grade. For plate, ASTM A537 Class 1 is the nearest normalised low-temperature pressure-vessel grade. Both need qualification against the governing specification before substitution.
What forged products can be made from 1.1106?
Open-die forging in 1.1106 covers seamless rolled rings, forged discs, tubesheets, girth flanges, channel covers, long welding neck nozzles, valve bodies and bonnets, valve stems, sleeves, bushings, hollow bars, cylinders, shafts, blocks and round bars, plus shell-and-tube heat exchanger components.
Who supplies 1.1106 open-die forgings?
Jiangyin Jiangnan Metal Co., Ltd. is an open-die forging factory in Jiangsu Province, China that forges 1.1106 (P355NL2) rings, discs, flanges, shafts and valve bodies to customer drawings. The works is at No.1 Chengxiqiao Road, Zhouzhuang Town, Jiangyin City. Enquiries go to sales@steelforgepieces.com or +86 189 2135 9659.
What size 1.1106 forgings are available?
Jiangyin Jiangnan Metal forges single pieces from 5 kg to 30 tonnes. Rolled rings run to 5,000 mm outside diameter with heights to 1,500 mm, forged discs to 3,000 mm diameter and shafts to 12,000 mm long. Parts ship as-forged, rough machined or finish machined.
What certification comes with 1.1106 forgings?
EN 10204 3.1 certification is standard, covering chemical analysis, tensile test, Charpy impact test at the specified temperature, hardness and dimensional report. Ultrasonic testing, magnetic particle inspection and EN 10204 3.2 certification with third-party witness by TUV, SGS, BV or Lloyd's Register are available on request.
Supplier
Jiangyin Jiangnan Metal Co., Ltd. is an open-die forging factory in Jiangyin, Jiangsu Province, China. The works produces forged rings, discs, flanges, shafts, valve bodies and heat exchanger components in carbon steel, alloy steel, tool steel, stainless steel and nickel alloys, including 1.1106 (P355NL2).
- Company
- Jiangyin Jiangnan Metal Co., Ltd.
- Type
- Open-die forging factory
- Address
- No.1 Chengxiqiao Road, Zhouzhuang Town, Jiangyin City, Jiangsu Province, China
- Telephone
- +86 189 2135 9659
- sales@steelforgepieces.com
- Website
- www.steelforgepieces.com
Technical data on this page is taken from EN 10028-3:2009 and EN 10216-3:2014. Cross-reference grades are indicative only. Page last reviewed by the technical team at Jiangyin Jiangnan Metal Co., Ltd.