Heat Resistant & Cr-Mo
ER80S-B8 for P9 & T9
ER80S-B8 welding wire is an AWS A5.28 low-alloy Cr-Mo solid welding wire for P9, T9 and other compatible 9Cr-1Mo steels used in high-temperature industrial applications. ER80S-B8 is a 9Cr-1Mo low-alloy welding wire designed for compatible P9 and T9 steels. It is commonly used for high-temperature piping, refinery equipment, petrochemical facilities, pressure vessels and other demanding industrial applications.
ER80S-B8 Welding Wire
ER80S-B8 is an AWS A5.28 low-alloy solid welding wire for compatible 9Cr-1Mo steels such as P9 and T9.
It is part of the 9Cr-1Mo Cr-Mo welding consumable family and is used where weld-metal chemistry must be compatible with heat-resistant low-alloy steels used in elevated-temperature service.
Typical applications include:
- P9 and T9 piping
- High-temperature process piping
- Refinery and petrochemical equipment
- Heat exchangers
- Pressure equipment
- Furnace components
- Boiler and heat-transfer equipment
- Industrial high-temperature systems
ER80S-B8 is available in product forms for GMAW/MIG and GTAW/TIG, subject to product specification and the qualified welding procedure.
ER80S-B8 at a Glance
Item | Details |
|---|---|
AWS Classification | ER80S-B8 |
Specification | AWS A5.28 / ASME SFA-5.28 |
Alloy System | 9Cr-1Mo |
Strength Class | ER80 |
Typical Base Materials | P9, T9 and compatible 9Cr-1Mo steels |
Welding Processes | GMAW/MIG, GTAW/TIG |
Typical Applications | High-temperature piping, refinery, petrochemical and industrial equipment |
Product Form | Solid wire / TIG rod |
Documentation | TDS, MTC/CoA and project documentation as required |
9Cr-1Mo: The Material System Behind ER80S-B8
The defining feature of ER80S-B8 is its 9Cr-1Mo weld-metal chemistry.
This places B8 in a different consumable family from:
- B2 — 1.25Cr-0.5Mo
- B3 — 2.25Cr-1Mo
- B6 — 5Cr-0.5Mo
- B91 — modified Grade 91 system
- B92 — modified Grade 92 system
For B8 applications, the base material is the starting point for consumable selection.
Typical associated materials include:
- ASTM A335 P9
- ASTM A213 T9
- ASTM A182 F9
- ASTM A387 Grade 9
- ASTM A234 WP9
- Other compatible 9Cr-1Mo steels
The appropriate filler metal should always be confirmed against the applicable code and qualified WPS/PQR.
ER80S-B8 Chemical Composition
ER80S-B8 is based on a controlled 9Cr-1Mo Cr-Mo chemistry.
Typical classification requirements include:
Element | Typical / Classification Requirement, wt.% |
|---|---|
C | ≤0.10 |
Mn | 0.40–0.70 |
Si | ≤0.50 |
Cr | 8.00–10.50 |
Mo | 0.80–1.20 |
Ni | ≤0.50 |
Cu | ≤0.35 |
P | ≤0.025 |
S | ≤0.025 |
These values describe classification requirements rather than the exact chemistry of every production batch.
For procurement, actual chemical composition should be checked against the supplied TDS and MTC/CoA.
Mechanical Properties
ER80S-B8 belongs to the ER80 strength classification.
Typical minimum classification values include:
Property | Minimum |
|---|---|
Yield Strength | 470 MPa / 68 ksi |
Tensile Strength | 550 MPa / 80 ksi |
Elongation | 17% |
Actual weld-metal performance can vary with welding process, shielding gas, heat input, welding parameters and PWHT.
For critical applications, the applicable WPS/PQR and product MTC should be used to verify project-specific requirements.
P9 and T9 Welding Applications
P9 Welding Wire
P9 welding wire is one of the primary search and purchasing applications for ER80S-B8.
P9 is a 9Cr-1Mo steel used in elevated-temperature equipment.
ER80S-B8 may be considered for compatible P9 applications such as:
- High-temperature process piping
- Refinery piping
- Heat exchangers
- Furnace components
- Pressure equipment
- Thermal-process systems
The filler metal should be selected according to the material specification and qualified welding procedure.
T9 Welding Wire
T9 welding wire is another important application for B8.
T9 is used in heat-transfer and elevated-temperature equipment, including applications involving:
- Boiler components
- Heat-transfer tubes
- High-temperature tubing
- Process equipment
- Industrial heating systems
Actual consumable selection and welding parameters must follow the applicable WPS/PQR.
Why 9Cr-1Mo Matters
The high chromium content distinguishes B8 from lower-chromium Cr-Mo consumables.
The B8 chemistry provides a weld-metal system designed around:
9Cr + 1Mo + Controlled Weld-Metal Chemistry
This is why ER80S-B8 should not be selected merely because it has an ER80 strength designation.
For Cr-Mo welding, the important question is:
Does the filler metal match the base-metal alloy system and qualified welding procedure?
That approach is more reliable than selecting a consumable based only on tensile strength.
ER80S-B8 in High-Temperature Equipment
B8 is associated with industrial equipment where 9Cr-1Mo materials are used for elevated-temperature service.
Typical application areas include:
Refinery and Petrochemical
- Process piping
- High-temperature piping
- Heat exchangers
- Furnace equipment
- Pressure equipment
Power and Thermal Systems
- Boiler components
- High-temperature piping
- Heat-transfer equipment
- Thermal-process systems
Industrial Equipment
- 9Cr-1Mo components
- High-temperature process equipment
- Compatible pressure equipment
- Furnace and heating systems
Application suitability depends on the base material, service conditions, welding procedure and applicable construction code.
ER80S-B8 Welding Processes
GMAW / MIG
ER80S-B8 can be supplied as solid wire for GMAW/MIG welding.
The qualified procedure may control:
- Wire diameter
- Shielding gas
- Current
- Voltage
- Wire-feed speed
- Travel speed
- Heat input
Actual welding parameters should be taken from the approved WPS.
GTAW / TIG
B8 can also be supplied as TIG filler rod.
GTAW may be used where controlled deposition and precise welding are required, including suitable pipe and critical-joint applications.
Shielding gas, purge requirements and welding parameters should follow the qualified procedure.
P9 Welding Procedure: Thermal Control
For P9 and T9 welding, thermal-cycle control is an important part of weld procedure qualification.
Depending on material thickness, joint configuration, welding process and applicable code, the WPS may establish requirements for:
Preheat → Interpass Temperature → Heat Input → Cooling → PWHT
There is no single generic temperature schedule that should be copied from a product page.
The exact requirements should come from the approved WPS/PQR, material specification and applicable construction code.
Choosing Between B8 and Other Cr-Mo Consumables
The fastest way to narrow the selection is to start with the base-material grade.
Base Material | Commonly Associated Consumable |
|---|---|
P11 / T11 | ER80S-B2 |
P22 / T22 | ER90S-B3 |
P5 / T5 | ER80S-B6 |
P9 / T9 | ER80S-B8 |
P91 / T91 | ER90S-B91 |
P92 / T92 | ER90S-B92 |
This table is a selection guide, not a substitution rule. The actual WPS/PQR and applicable code determine the qualified consumable.
ER80S-B8 vs ER80S-B6
Both are ER80-class Cr-Mo consumables, but they belong to different alloy systems.
| ER80S-B8 | ER80S-B6 |
|---|---|---|
Alloy System | 9Cr-1Mo | 5Cr-0.5Mo |
Typical Steel | P9 / T9 | P5 / T5 |
Strength Class | ER80 | ER80 |
Chromium | ~9% | ~5% |
Molybdenum | ~1% | ~0.5% |
P9/T9 → B8
P5/T5 → B6
ER80S-B8 vs ER90S-B3
The key difference is the base-metal alloy system, not simply ER80 versus ER90.
| ER80S-B8 | ER90S-B3 |
|---|---|---|
Alloy System | 9Cr-1Mo | 2.25Cr-1Mo |
Typical Steel | P9 / T9 | P22 / T22 |
Strength Class | ER80 | ER90 |
Chromium | ~9% | ~2.25% |
Molybdenum | ~1% | ~1% |
P9/T9 → B8
P22/T22 → B3
ER80S-B8 vs ER80S-B2
| ER80S-B8 | ER80S-B2 |
|---|---|---|
Alloy System | 9Cr-1Mo | 1.25Cr-0.5Mo |
Typical Steel | P9 / T9 | P11 / T11 |
Strength Class | ER80 | ER80 |
Chromium | ~9% | ~1.25% |
Molybdenum | ~1% | ~0.5% |
The difference in Cr-Mo chemistry means B8 and B2 should not be treated as interchangeable simply because both are ER80-class wires.
ER80S-B8 vs ER90S-B91
Both are associated with approximately 9% chromium steels, but their alloy systems are different.
| ER80S-B8 | ER90S-B91 |
|---|---|---|
Typical Steel | P9 / T9 | P91 / T91 |
Alloy System | 9Cr-1Mo | Modified 9Cr-1Mo-V-Nb |
Strength Class | ER80 | ER90 |
Additional Alloying | — | V, Nb and controlled additions |
Typical Role | 9Cr-1Mo applications | Grade 91 applications |
P9/T9 ≠ P91/T91
A Grade 91 application should use the appropriate qualified Grade 91 consumable system rather than assuming B8 is an alternative.
ER80S-B8 vs ER90S-B92
| ER80S-B8 | ER90S-B92 |
|---|---|---|
Typical Steel | P9 / T9 | P92 / T92 |
Alloy System | 9Cr-1Mo | Modified 9Cr-W-Mo-V-Nb |
Strength Class | ER80 | ER90 |
Typical Service | High-temperature | High-temperature / creep-resistant |
Typical Role | 9Cr-1Mo applications | Grade 92 applications |
P9/T9 → B8
P92/T92 → B92
ER80S-B8 vs ER90S-B9
ER90S-B9 is associated with the older Grade 91 consumable designation, while ER90S-B91 is the current classification used for Grade 91 applications.
Therefore:
P9/T9 → ER80S-B8
P91/T91 → current Grade 91 consumable system
For projects using older drawings or specifications, verify the exact filler-metal designation before purchasing.
Diameter and Product Forms
ER80S-B8 can be supplied in different diameters and product forms according to welding process and customer requirements.
Available forms may include:
- GMAW/MIG spools
- GTAW/TIG rods
- Different wire diameters
- Standard industrial packaging
- Customized packaging where available
For quota
