Gangsteel supplies EN 10028-6 P355QH steel plate for boilers, pressure vessels and other pressure equipment that specify this weldable fine-grain steel in the quenched and tempered condition. P355QH (steel number 1.8867) is the series with elevated-temperature properties (P…QH) in the P355 strength class of EN 10028-6, together with EN 10028-6 P355Q, EN 10028-6 P355QL1, EN 10028-6 P355QL2. In accordance with EN 10020, all steels specified in EN 10028-6 are alloy special steels. The products shall be supplied in the quenched and tempered condition (+QT). This is not the normalized or normalizing-rolled condition of EN 10028-3 and not the thermomechanically rolled condition of EN 10028-5. Within the pressure-vessel and boiler steel plate range, Gangsteel coordinates mill production, plate processing and export supply around the contractual edition and the requirements of each order.
This page is a full-site official-style product-body remediation under the existing parent category pressure-vessel and boiler steel plate. It is not part of the named official-product-standards hubs, and no child EN 10028-6 taxonomy is created. The current published edition is EN 10028-6:2017 (BS EN 10028-6:2017, 31 August 2017; approved by CEN on 7 May 2017), which supersedes EN 10028-6:2009. The general requirements of EN 10028-1:2017 also apply. Delivery-condition wording (products shall be supplied quenched and tempered), the four quality series (P…Q basic; P…QH elevated temperature; P…QL1 low temperature down to −40 °C; P…QL2 low temperature down to −60 °C), and the classification of all these steels as alloy special steels follow official EN 10028-6:2003 clauses 6.1 and 8.2.1, which BSI’s 2017 change list does not revise. Cast-analysis chemistry (Table 1), product-analysis deviations (Table 2), room-temperature tensile properties (Table 3), transverse impact energy (Table 4) and elevated-temperature 0,2 % proof strength for the QH grades (Table 5) are the official EN 10028-6:2003 specified-band values, visually confirmed on the official British Standard pages, including the phosphorus and sulphur quality split and the Table 3 yield and tensile cell layout. BSI’s published summary of the 2017 revision lists: revised normative references; deletion of the option to agree thicknesses greater than those stated and the corresponding footnote in Table 3; consideration of EN 1011-1 and EN 1011-2 as normative references; deletion of one- and two-dot markings; removal of notes 1 and 2 in subclause 8.2.2 concerning welding conditions; an update of the copper-plus-tin data in Table 1 (official 2017 Table 1 was not obtained in this pass, so the contractual edition governs any revised Cu+Sn figures; the 2003 option for a lower copper content and a maximum tin content by agreement is noted, without inventing 2017 numbers); extension of the maximum thickness to 200 mm (official 2017 Table 3 values for t > 150 mm were not obtained and are not fabricated; the 2003 “other product thicknesses may be agreed” footnote is not used); a new informative annex on weldability; and an Annex ZA update to Directive 2014/68/EU. The sixteen grades on this site are the complete EN 10028-6 Table 1 set; no pages are invented. EN 10028-2 P265GH is the existing EN 10028-2 product page (category 1, not 980), drafted in the same publication manifest and not treated as a Part 6 grade. No figure from EN 10028-2, EN 10028-3, EN 10028-5, EN 10025-6, ASTM or ASME is presented as an EN 10028-6 requirement. The contractual edition named on the purchase order, the mill certificate and EN 10028-1 govern.
Grade Designation
- Standard: EN 10028-6 (current published edition EN 10028-6:2017; tabulated specified-band values from official EN 10028-6:2003, as disclosed in the unlabelled context above).
- Steel name: P355QH.
- Steel number: 1.8867.
- Classification: alloy special steel (EN 10028-6 clause 6.1.2, EN 10020).
- Quality series: the series with elevated-temperature properties (P…QH).
- Usual delivery condition: quenched and tempered (+QT), EN 10028-6 clause 8.2.1.
- Tabulated thickness in official 2003 Table 3 and Table 4: up to 150 mm. EN 10028-6:2017 extended the maximum thickness to 200 mm; official 2017 Table 3 values for t > 150 mm were not obtained and are not stated here.
Key Advantages of EN 10028-6 P355QH Steel Plate
- Specified quenched and tempered delivery, with a minimum yield strength of 355 MPa in the t ≤ 50 mm band.
- Fine-grain alloy special steel for pressure equipment, with a heat-analysis chemistry that is tighter on phosphorus and sulphur for the QL qualities than for Q and QH.
- Official Table 4 transverse impact energy of 27 J minimum at −20 °C for the P355QH quality, over 5 mm to 150 mm.
- Official Table 5 minimum Rp0,2 values at elevated temperature (50 °C to 300 °C) for this QH grade, to be proven by an elevated-temperature tensile test for the specified service temperature by agreement (Table 5 footnotes a and c).
- Weldable under processes in current use; welding-condition data may be requested from the manufacturer (clause 8.2.3). Excessive post-weld heat treatment can decrease mechanical properties (2003 Note 3).
Chemical Composition of EN 10028-6 P355QH Steel Plate
| Element | Cast (heat) analysis, mass % |
|---|---|
| C | ≤ 0.16 |
| Si | ≤ 0.40 |
| Mn | ≤ 1.50 |
| P | ≤ 0.025 |
| S | ≤ 0.015 |
| N | ≤ 0.015 |
| B | ≤ 0.005 |
| Cr | ≤ 0.30 |
| Mo | ≤ 0.25 |
| Cu | ≤ 0.30 |
| Nb | ≤ 0.05 |
| Ni | ≤ 0.50 |
| Ti | ≤ 0.03 |
| V | ≤ 0.06 |
| Zr | ≤ 0.05 |
Cast (heat) analysis, official EN 10028-6:2003 Table 1, visually confirmed. The phosphorus and sulphur maxima for P355QH are the official values for the QH quality (Q and QH: P ≤ 0.025 % and S ≤ 0.015 %; QL1 and QL2: P ≤ 0.020 % and S ≤ 0.010 %). EN 10028-6:2017 updated the copper-plus-tin data in Table 1; official 2017 Table 1 was not obtained, and no revised Cu+Sn figures are invented here. For reasons of hot formability, a lower copper content and a maximum tin content may be agreed (2003 Table 1 footnote c).
The percentage of grain-refining elements shall be at least 0.015 %; aluminium is included. The 0.015 % minimum applies to dissolved aluminium and is regarded as attained if the total aluminium content is at least 0.018 % (Table 1 footnote d). The manufacturer may add one or several alloying elements up to the Table 1 maxima, as a function of thickness and steelmaking, in order to attain the specified properties; the manufacturer’s composition range shall be given in the offer and order confirmation (footnote b). Product analysis may deviate from the Table 1 cast-analysis limits by the permissible amounts in official Table 2. Elements not listed shall not be intentionally added without purchaser agreement, except for finishing the cast (footnote a).
Mechanical Properties of EN 10028-6 P355QH Steel Plate
| Product thickness t (mm) | Yield strength ReH min (MPa) | Tensile strength Rm (MPa) | Elongation A min (%) |
|---|---|---|---|
| t ≤ 50 | 355 | 490–630 | 22 |
| 50 < t ≤ 100 | 335 | 490–630 | 22 |
| 100 < t ≤ 150 | 315 | 450–590 | 22 |
Room-temperature mechanical properties, official EN 10028-6:2003 Table 3, visually confirmed, for the quenched and tempered condition. The yield strength to be determined shall be the upper yield strength ReH or, if this is not pronounced, the 0,2 % proof strength Rp0,2 (Table 3 footnote a). Tensile strength is specified in two thickness bands (t ≤ 100 mm and 100 < t ≤ 150 mm); elongation is a single official minimum through 150 mm. These figures apply to all four qualities in the P355 class. EN 10028-6:2017 deleted the option to agree other product thicknesses (2003 Table 3 footnote b) and extended the maximum thickness to 200 mm; official 2017 values for t > 150 mm were not obtained and are not stated here.
Impact energy (transverse test pieces)
| Steel quality | Product thickness (mm) | KV min (J) at −60 °C | KV min (J) at −40 °C | KV min (J) at −20 °C | KV min (J) at 0 °C | KV min (J) at +20 °C |
|---|---|---|---|---|---|---|
| P355QH | 5 to 150 | — | — | 27 | 40 | 60 |
Impact energy, official EN 10028-6:2003 Table 4, valid for transverse test pieces, visually confirmed. A dash (—) means no value is specified in the table at that temperature. For P355QH, the official design temperature of this quality series is −20 °C, with a minimum of 27 J. The Table 4 thickness range is 5 mm to 150 mm (footnote a refers to EN 10028-1 for the lower bound). Longitudinal impact values are not tabulated in official Table 4 and are not invented here. Mid-thickness impact test pieces, and the associated temperatures and energy values, may be agreed (2003 option 7.2 a / clause 10); agreed figures are not invented here.
Minimum 0,2 % proof strength at elevated temperature (Rp0,2, MPa)
| Product thickness t (mm) | 50 °C | 100 °C | 150 °C | 200 °C | 250 °C | 300 °C |
|---|---|---|---|---|---|---|
| t ≤ 50 (official Table 5 values) | 340 | 310 | 285 | 260 | 235 | 215 |
| 50 < t ≤ 100 (Table 5 footnote c: −20 MPa) | 320 | 290 | 265 | 240 | 215 | 195 |
| t > 100 mm, through the 2003 tabulated 150 mm (Table 5 footnote c: −60 MPa) | 280 | 250 | 225 | 200 | 175 | 155 |
Minimum 0,2 % proof strength Rp0,2 at elevated temperature, official EN 10028-6:2003 Table 5, visually confirmed, for P355QH. The first row is the official tabulated values, which are valid for product thicknesses t ≤ 50 mm. The second and third rows apply the official footnote c reductions (−20 MPa for 50 < t ≤ 100 mm and −60 MPa for t > 100 mm) to those tabulated values; they are not separately printed numbers on the 2003 page. The values shall be proven by a tensile test at elevated temperature for the specified service temperature; an agreement at enquiry and order shall be reached between purchaser and manufacturer (Table 5 footnote a). If agreed, these values also apply to the corresponding P…QL grades (footnote b). Table 5 ends at 300 °C; no 350 °C or 400 °C figures are specified and none are invented. Official 2017 values for any thickness above 150 mm were not obtained.
Delivery Condition, Tests and Heat Treatment
The products covered by EN 10028-6 shall be supplied in the quenched and tempered condition (clause 8.2.1). This is not the normalized or normalizing-rolled delivery of EN 10028-3 and not the thermomechanically rolled delivery of EN 10028-5. Inspection and inspection documents follow EN 10028-1 and EN 10204. The steels shall be suitable for welding processes in current use; the manufacturer shall, if requested, provide data on suitable welding conditions determined from weld-procedure tests (clause 8.2.3). Excessive post-weld heat treatment can decrease mechanical properties; verification on simulated PWHT samples may be considered at enquiry and order (2003 Note 3). EN 10028-6:2017 removed notes 1 and 2 in subclause 8.2.2 concerning welding conditions and added an informative annex on weldability. Optional items include mid-thickness impact test pieces (option 7.2 a / clause 10). The purchaser specifies the contractual edition, thickness, dimensions, inspection document and any agreed options.
Available Dimensions of EN 10028-6 P355QH Steel Plate
Official EN 10028-6:2003 Table 3 and Table 4 tabulate mechanical and impact properties through 150 mm. EN 10028-6:2017 extended the maximum thickness to 200 mm; official 2017 Table 3 values for t > 150 mm were not obtained and are not stated as specified properties on this page. Width, length and any processing (cutting, bevelling, forming within the agreed condition) are as specified on the order and as the mill can produce. Gangsteel does not publish a standing stock list on this page. The purchaser should state the required thickness, dimensions and quantity at enquiry.
Main Applications of EN 10028-6 P355QH Steel Plate
EN 10028-6 P355QH is specified for flat products for pressure equipment, including service that uses the official Table 5 elevated-temperature Rp0,2 values for this QH grade, when those values are proven as required by Table 5 footnote a. Typical uses include boilers, pressure vessels, heat exchangers and related pressure parts, where the purchase order names this grade, the contractual edition and the quenched and tempered delivery. Suitability for a given design code, service temperature, thickness and welding procedure is a matter for the purchaser’s specification and the mill certificate, not a substitution from another EN 10028 part.
Equivalent Grades of EN 10028-6 P355QH Steel Plate
The following existing Gangsteel product pages are corresponding grades that are often discussed alongside P355QH. Correspondence is not automatic substitution. The purchase order must name the standard, the grade, the edition and the delivery condition.
| Standard | Grade | Qualification |
|---|---|---|
| EN 10028-6 | P355Q, P355QL1, P355QL2 | Same Table 3 tensile class and the same strength-class chemistry, except the QL phosphorus and sulphur limits. Each quality has its own Table 4 impact series and, for QH, basic Table 5 elevated-temperature values. Not automatic substitutes for P355QH. |
| EN 10028-3 | P355N, P355NH, P355NL1, P355NL2 | Normalized (or normalizing-rolled) Part 3 fine-grain grades in the same 355 yield class. Delivery, thickness steps, impact temperatures (NL2 is −50 °C, not the Part 6 QL2 −60 °C) and chemistry are those of EN 10028-3, not of quenched and tempered P355Q-series plate. Not automatic substitutes. |
| EN 10028-5 | P355M, P355ML1, P355ML2 | Thermomechanically rolled Part 5 grades in the 355 class, tabulated only through 63 mm, with a different Rm range and with ML2 impact at −50 °C. Not the quenched and tempered condition of this page. Not automatic substitutes. |
| EN 10028-2 | P355GH | Non-alloy quality elevated-temperature grade of Part 2, usual +N delivery, with its own Table 1 chemistry and Table 3/4 properties. Not an automatic substitute for quenched and tempered Part 6 plate. |
| ASTM / ASME | ASTM A516 Grade 70, ASME SA516 Grade 70 | Widely specified carbon steel plate for pressure vessels under ASTM/ASME rules. Chemistry, heat treatment, thickness steps and impact are those of A516/SA516, not of EN 10028-6. Not automatic substitutes. |
Related Products
- EN 10028-6 P355Q — same strength class, different quality series, not an automatic substitute.
- EN 10028-6 P355QL1 — same strength class, different quality series, not an automatic substitute.
- EN 10028-6 P355QL2 — same strength class, different quality series, not an automatic substitute.
- EN 10028-6 P460QH — adjacent Part 6 strength class in the same quality series.
- EN 10028-3 P355NH and EN 10028-5 P355M — same nominal 355 class, different parts and delivery conditions.
- EN 10028-2 P355GH — Part 2 elevated-temperature grade, usual +N delivery.
- EN 10028-2 P265GH — Part 2 non-alloy quality grade on the same pressure-vessel range (category 1).
- Pressure-vessel and boiler steel plate — parent category range.
FAQ about EN 10028-6 P355QH Steel Plate
What is EN 10028-6 P355QH steel plate?
EN 10028-6 P355QH (steel number 1.8867) is a weldable fine-grain alloy special steel for pressure purposes in EN 10028-6. It is the series with elevated-temperature properties (P…QH). Products shall be supplied quenched and tempered (+QT). Aliases used in enquiries include P355 QH, EN 10028-6 P355QH, 1.8867, P355QH QT.
What is the usual delivery condition of EN 10028-6 P355QH?
EN 10028-6 P355QH shall be supplied in the quenched and tempered condition (EN 10028-6 clause 8.2.1). That is not the normalized or normalizing-rolled condition of EN 10028-3 and not the thermomechanically rolled condition of EN 10028-5.
What is the chemical composition of EN 10028-6 P355QH?
The official EN 10028-6:2003 Table 1 cast (heat) analysis for EN 10028-6 P355QH is given in the chemical-composition table on this page, including P ≤ 0.025 % and S ≤ 0.015 % for this quality. Product analysis may deviate by official Table 2 amounts. EN 10028-6:2017 updated copper-plus-tin data in Table 1; official 2017 Table 1 was not obtained, and revised Cu+Sn figures are not invented here.
What are the yield, tensile and elongation values of EN 10028-6 P355QH?
For EN 10028-6 P355QH, official Table 3 gives a minimum yield strength of 355 MPa at t ≤ 50 mm, then 335 MPa at 50 < t ≤ 100 mm and 315 MPa at 100 < t ≤ 150 mm, a tensile range of 490–630 MPa at t ≤ 100 mm, and a minimum elongation of 22 %. These values apply to all four qualities in the P355 class. Official 2017 properties for t > 150 mm are not stated here.
What is the impact energy of EN 10028-6 P355QH?
Official Table 4, for transverse test pieces 5 mm to 150 mm thick, specifies 27 J minimum at −20 °C for the QH series, with the further temperatures shown in the impact table on this page. A dash means no official value at that temperature. Longitudinal values are not tabulated and are not invented. Mid-thickness tests may be agreed, with agreed temperatures and energies.
Does EN 10028-6 P355QH have elevated-temperature proof-strength values?
Yes. Official Table 5 specifies minimum Rp0,2 values for EN 10028-6 P355QH from 50 °C to 300 °C, valid for t ≤ 50 mm, with official reductions of 20 MPa (50 < t ≤ 100 mm) and 60 MPa (t > 100 mm). The values shall be proven by an elevated-temperature tensile test for the specified service temperature, by agreement (Table 5 footnote a).
Is EN 10028-6 P355QH the same as the Part 3 or Part 5 grade of the same yield class?
No. EN 10028-6 P355QH is a quenched and tempered EN 10028-6 steel. EN 10028-3 grades are normalized or normalizing-rolled, and EN 10028-5 grades are thermomechanically rolled, with their own chemistry, thickness limits, tensile ranges and impact temperatures (Part 3 NL2 and Part 5 ML2 are −50 °C; Part 6 QL2 is −60 °C). They are not automatic substitutes. Existing corresponding pages are linked in Equivalent Grades.
What thickness can EN 10028-6 P355QH be supplied in?
Official 2003 Tables 3 and 4 tabulate properties through 150 mm. EN 10028-6:2017 extended the maximum thickness to 200 mm, but official 2017 Table 3 values for t > 150 mm were not obtained and are not stated here. Width, length and quantity are as specified on the order. This page does not publish a standing stock list.
How do I enquire for EN 10028-6 P355QH steel plate?
Please contact Gangsteel with the grade P355QH (or steel number 1.8867), the contractual edition of EN 10028-6, thickness and dimensions, inspection document (EN 10204 3.1 or 3.2), and any agreed options: mid-thickness impact, welding-condition data, ultrasonic testing and EN 10164 through-thickness properties. Visit Gangsteel or contact Gangsteel to place the enquiry.
For production, processing and export enquiries for EN 10028-6 P355QH steel plate, please contact Gangsteel. Visit Gangsteel for the full plate-supply range.