High-strength steels
FERVEO HTS 550B5
covered electrode · stick electrodebasic coatingCatalogue only
AWS class
~ E 9018-D1 H4
EN ISO class
E 55 5 MnMo B 42 H5
Tensile strength (Rm)
620–780 MPa
Classification
| AWS class | ~ E 9018-D1 H4 |
|---|---|
| EN ISO class | E 55 5 MnMo B 42 H5 |
Purpose
- Nickel-free, Mn-Mo low-hydrogen basic electrode (AWS ~E 9018-D1 H4, EN ISO E 55 5 MnMo B 42 H5) — an alternative to the NiMo sub-family at the same mechanical-strength step.
Why it works
The Mn-Mo alloy system (no Ni) reaches the same mechanical-strength step as the 550B6 NiMo sub-family through a different, simpler alloying route, with good aging resistance; also useful for high-strength rail-steel repair.
Fields of application
- High-strength fine-grained structural steel and high-temperature steel, including rail repair up to 785 N/mm², with declared service down to -50°C.
Chemical composition
| Element | Typical, % |
|---|---|
| C | 0.075 |
| Mn | 1.6 |
| Mo | 0.45 |
| Si | 0.4 |
Mechanical properties
| Tensile strength (Rm) | 620–780 MPa |
|---|---|
| Yield strength (Rp0.2) | 550 MPa |
| Elongation (A5) | 18 % |
| Impact energy (KV) | 47 J (−50 °C) |
Process
| Polarity | DC+ |
|---|---|
| Positions | PAflatPBhorizontal-verticalPChorizontalPDhorizontal-overheadPEoverheadPFvertical-up |
| Re-drying | 300–350 °C / ≥2 h |
| Heat treatment | 560-600°C / 1h / |
Sizes and part numbers
| Ø | Length | Current | Request |
|---|---|---|---|
| 2.5 mm | 350 mm | 80–110 A | |
| 3.2 mm | 350 mm | 100–140 A | |
| 4 mm | 450 mm | 130–190 A | |
| 5 mm | 450 mm | 190–240 A |
Cross-reference
| Replaces OK 74.78 (ESAB) | Direct replacement |
| Replaces AS DA-737 (Askaynak) | Direct replacement |
Equivalence refers to the classification (AWS / EN ISO), not to product identity. In applications with a qualified procedure (WPS), validate the substitution before use.
Base metals
E295-E360P355GH17MnMoV6-415NiCuMoNb5SS380N-S500NP380NH-S500NHGE300-GE340G22Mo4API 5L: X52X56X60X65X70
Advantages
- Good resistance to aging in addition to cracking — relevant in long-duration service.
- Nickel-free Mn-Mo alloy system, a simpler alternative to the NiMo sub-family at the same strength step.
Limitations
- Toughness certified at -50°C, less demanding than the 550B6 NiMo sub-family (-60°C) — use that sub-family for colder service.