Steel P92 · supply condition · default condition
Steel P92-HR
Properties of the HR condition, compared with the other P92 tempers.
As-hot-worked mill stock with uncontrolled, position-dependent properties; never acceptable for code pressure parts without normalizing and tempering.
What is P92-HR?
P92-HR is P92 supplied in the HR condition — as-hot-worked mill stock with uncontrolled, position-dependent properties; never acceptable for code pressure parts without normalizing and tempering. P92-HR has a yield strength of 620 MPa (89.9 ksi) and a tensile strength of 850 MPa (123 ksi) — stronger than 78% of steel grades. Elongation at break is 17% and the elastic modulus is 218 GPa (31.6 Msi). P92-HR has a density of 7.78 g/cm³ (0.281 lb/in³), lighter than 91% of steel grades. It melts at 1,425°C (2,597 °F).
Advantages
- High service temperature — 620°C (1,148 °F), better than 99% of steel grades
- Good corrosion resistance — 30/100, better than 95% of steel grades
- Tough — resists crack growth — 130 MPa·√m (118.3 ksi·√in), better than 89% of steel grades
- High strength — 620 MPa (89.9 ksi), better than 78% of steel grades
Limitations
- Difficult to machine — 28/100, worse than 91% of steel grades
- High embodied carbon — 2.6 kg CO₂/kg, worse than 86% of steel grades
- Poor heat conductor — 28 W/m·K (16.2 BTU/hr·ft·°F), worse than 85% of steel grades
P92-HR properties
Typical room-temperature values for P92-HR — 7 properties are specific to this condition; the rest are grade-level values shared by every P92 temper. Each bar shows where the value sits among the steel grades in FabDigit's library — further right is higher.
Physical3
P92-HR has a density of 7.78 g/cm³ (0.281 lb/in³), lighter than 91% of steel grades. It melts at 1,425°C (2,597 °F).
Mechanical16
P92-HR has a yield strength of 620 MPa (89.9 ksi) and a tensile strength of 850 MPa (123 ksi) — stronger than 78% of steel grades. Elongation at break is 17% and the elastic modulus is 218 GPa (31.6 Msi).
Thermal6
P92-HR is rated for continuous service to 620°C (1,148 °F). It conducts heat at 28 W/m·K (16.2 BTU/hr·ft·°F), worse than 85% of steel grades. Thermal expansion is 10.8 µm/m·K (6 µin/in·°F).
Electrical2
P92-HR has an electrical resistivity of 5.9×10⁻⁷ Ω·m.
Chemical & Environmental2
Corrosion resistance is poor (30/100), better than 95% of steel grades.
Sustainability4
Producing a kilogram of P92-HR takes about 36 MJ of energy and emits 2.6 kg of CO₂ — more than 88% of steel grades. Typical recycled content is 30%.
Manufacturability7
P92-HR's machinability is poor (28/100, worse than 91% of steel grades); weldability fair (40/100); formability fair (35/100).
Common Calculations5
Values are nominal handbook figures for design screening. Certified mill or lot data ships with every FabDigit order on request.
Other P92 tempers and conditions
P92 is also supplied in 4 other conditions. The full side-by-side table is on the P92 overview.
- HRDefaultAs-hot-worked mill stock with uncontrolled, position-dependent properties; never acceptable for code pressure parts without normalizing and tempering.620 MPa yield · 29 HRC
- NormalizedProcess-only condition after air cooling from austenitizing — hard and brittle, must be tempered before any service or hydro test.900 MPa yield · 43 HRC
- Q&TUsed on thick forgings and castings where air cooling cannot fully harden the section; slightly higher strength than N&T at similar toughness.580 MPa yield · 23 HRC
- N&TThe only condition allowed for pressure service — tempered martensite with fine MX/M23C6 precipitation giving the design creep strength.540 MPa yield · 21 HRC
- AnnealedSoftened condition for heavy machining or cold forming; the creep properties are only restored after a full re-normalize and temper.400 MPa yield · 185 HB
Working with P92-HR
Is P92 easy to machine?
Machine in the N&T (≤250 HB) or annealed condition with rigid setups, coated carbide, moderate speed and heavy feed; the fine MX carbonitrides are abrasive and work-hardening is noticeable.
Can P92 be welded?
GTAW root / SMAW-FCAW fill with matching 9Cr-2W consumables, 200–250 °C preheat, interpass ≤300 °C, no interruption below preheat, mandatory PWHT 750–780 °C with careful hold time; watch Type IV cracking in the fine-grain HAZ and keep Ni+Mn low in filler.
Can P92 be formed, bent or molded?
Hot form at 1050–1150 °C followed by a full re-normalize and temper; cold bending is limited and any cold strain above a few percent should be re-heat-treated to restore creep strength.
What surface finishes work on P92?
Not stainless — protect with high-temperature aluminium/silicone paint, aluminizing or Cr-diffusion coating for steam-side oxidation and shot-blast/pickle before coating; anodizing is not applicable.
P92 chemical composition (wt %)
Limits by weight percent from the governing specification, written the way the spec states them — a single maximum for impurities, a range for alloying elements, and the base element as balance. Nominal is the typical mid-range value.
| Element | Spec limit (wt %) | Nominal |
|---|---|---|
| C | 0.07 – 0.13 | 0.1 |
| Si | ≤ 0.5 | 0.25 |
| Mn | 0.3 – 0.6 | 0.45 |
| P | ≤ 0.02 | 0.01 |
| S | ≤ 0.01 | 0 |
| Cr | 8.5 – 9.5 | 9 |
| W | 1.5 – 2 | 1.8 |
| Mo | 0.3 – 0.6 | 0.5 |
| V | 0.15 – 0.25 | 0.2 |
| Nb | 0.04 – 0.09 | 0.06 |
| N | 0.03 – 0.07 | 0.05 |
| B | 0 – 0.01 | 0 |
| Ni | ≤ 0.4 | 0.2 |
| Al | ≤ 0.02 | 0.01 |
| Ti | ≤ 0.01 | — |
| Zr | ≤ 0.01 | — |
| Fe | balance | — |
P92-HR — frequently asked
What is P92-HR used for?
P92-HR is typically used for ultra-supercritical main steam piping, hot reheat piping, boiler headers, high-temperature valve bodies, thick-wall forged fittings and superheater outlet tubing. In short: premium high-temp pipe.
What is the yield strength of P92-HR?
P92-HR has a typical yield strength of 620 MPa (89.9 ksi) and a tensile strength of 850 MPa (123 ksi) — stronger than 78% of steel grades. Strength varies by condition: see the 5 listed tempers.
Is P92-HR easy to machine?
Not especially — machinability is rated poor (28/100, worse than 91% of steel grades). Machine in the N&T (≤250 HB) or annealed condition with rigid setups, coated carbide, moderate speed and heavy feed; the fine MX carbonitrides are abrasive and work-hardening is noticeable.
Can P92-HR be welded?
With care — weldability is rated fair (40/100). GTAW root / SMAW-FCAW fill with matching 9Cr-2W consumables, 200–250 °C preheat, interpass ≤300 °C, no interruption below preheat, mandatory PWHT 750–780 °C with careful hold time; watch Type IV cracking in the fine-grain HAZ and keep Ni+Mn low in filler.
What surface finishes work on P92-HR?
Not stainless — protect with high-temperature aluminium/silicone paint, aluminizing or Cr-diffusion coating for steam-side oxidation and shot-blast/pickle before coating; anodizing is not applicable.
Can P92-HR be formed, bent or molded?
Hot form at 1050–1150 °C followed by a full re-normalize and temper; cold bending is limited and any cold strain above a few percent should be re-heat-treated to restore creep strength.
What is the maximum service temperature of P92-HR?
P92-HR is rated for continuous use to about 620°C (1,148 °F). Strength falls off well before that limit — check the elevated-temperature data for load-bearing parts.
Can FabDigit make parts in P92-HR?
Yes — P92-HR is available for CNC machining and sheet metal with instant online pricing. Upload a STEP file to get a price and a DFM check.
Sources
- ASTM A335/A335M — Seamless Ferritic Alloy-Steel Pipe for High-Temperature Service (Grade P92) — ASTM International (2022)
- ASME BPVC Section II Part A, SA-335 / SA-182 F92 — ASME (2023)
- EN 10216-2 — Seamless steel tubes for pressure purposes, X10CrWMoVNb9-2 (1.4901) — CEN (2020)
- GB/T 5310 — (10Cr9MoW2VNbBN) — SAC (2017)
- ASM Handbook Vol. 1 — Properties and Selection: Irons, Steels and High-Performance Alloys — ASM International (1990)
- VdTÜV-Werkstoffblatt 552 — X10CrWMoVNb9-2 physical and elevated-temperature data — VdTÜV (2015)
Property data is compiled from published supplier and standards handbooks and normalised for comparison. Nothing on this page is a certification — request mill certs, CoC or material test reports with your order.