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- 80-90ksi
80-90ksi
Application
Low-alloy high-strength steels offer excellent performance at elevated temperatures compared to C-Mn steels, making them ideal for manufacturing pressure vessels and related piping. These materials provide significant resistance to creep rupture and maintain ductility up to about 450 °C, also exhibiting good toughness at low temperatures. They are perfect for the production of high-strength steels intended for use in stress-relief conditions.
These consumables, characterized by a low nickel content, are specifically designed for the process piping and fittings of offshore oilwell head, conforming to the requirements of the NACE MR0175 standard. This ensures optimal resistance to sulfide stress cracking in sour environments, combined with good toughness even at subzero temperatures.
They are also used for the repair of medium-strength low-alloy steel castings, where only stress-relieving treatment, instead of normalizing and tempering (N+T), needs to be applied. The precise requirements for preheating and post-weld heat treatment (PWHT) depend on the base material to be welded. Typically, preheat/interpass temperatures are between 100 and 250 °C. A PWHT is required.
Alloy Type
Low alloy steel consumables with MnMo additions for welding high strength steels with ultimate tensile strength to 620 MPa (90ksi).
Microstructure
In the stress relieved condition the microstructure consists of tempered bainite.
Materials
- EN W.Nr.: P295 G H, P355 G H, 16Mo2, 17Mo3, 14Mo6, S275, S355, S420, S275, S355, S420
- ASTM: A 487 Gr 2A, 2B & 2C
Products of the line 80-90ksi
Product name | Process | AWS specifications | EN ISO specifications | |
DAIKOWT D2 | GTAW |
AWS A5.28
ER80S-D2* |
EN ISO 14341-A
W 4Mo |
|
G-TECH 80G | SMAW |
AWS A5.5
E8018-G |
EN ISO 18275-A
E 50 6 Mn1Ni B 42 |
|
G-TECH 90G | SMAW |
AWS A5.5
E9018-G |
EN ISO 18275-A
E 62 4 1NiMo B 42 |
|
DAIKOWM D2 | GMAW |
AWS A5.28
ER80S-D2* |
EN ISO 14341-A
G 4Mo |
|
DAIKOWS MnMo | SAW |
AWS A5.23
EA3 |
EN ISO 14171-A
S4Mo |