Application Technology
Shipbuilding
Along with hardware characterized by top performance shipbuilding steel, POSCO offers software represented by steel use skills consisting of welding and performance evaluation
Case Study
Application Technology generally adapted for parts is described below. Please contact us through ‘Contact Us > Q&A' for more details.
Brittle Crack Arrest Method for Ultra Large Containership
Brittle Crack Arrest Method
for Ultra Large Containership
Steel
Brittle Crack Arrest(BCA) Steels (EH40/47BCA, EH40/47BCACOD)
Application Technology
Prevent the unstable brittle fracture in weld joint of upper deck and Hatch-side coaming
Using the brittle crack arrest toughness excellent steel
- EH40/47BCA 100mmt, EH40/47BCACOD 100mmt
- Kca ≥ 6,000 N/mm1.5 or CAT < -10ºC
Applicaiotn of brittle crack arrest design
- Arrest hole, Arrest insert, Arrest weld
Benefits
Prevention of unstable fracture by applying a brittle crack arrest steels and design
High Efficiency-High Heat Input Welding
for Ultra Large Container Ships
Steel
Strucural steels for shipbuilding : EH/DH32-TMU, EH36-TMU, EH40-TMU
Application Technology
Development of high heat input welding technology for 1 pass welding of thick plates (max.85mm)
- Fine microstructure control in coarse-grain zone of HAZ by optimizing design of micro alloy elements
- Design of welded joints and development of welding consumables for excellent impact toughness
Benefits
Improvement of welding productivity for ultra large container with very thick plates
- High efficiency welding of very thick plates by 1 pass welding
- High performance of welded joints with excellent impact toughness
Application of High Strength Steel
for Low Temperature Service
Steel
E500(EH51)-TM
Application Technology
High adaptability for Arctic region by using high performance steel for low temperature service
Suggestion of welding consumables and welding conditions by evaluation of cold crack
susceptibility of welded joint with heat input range 1.0~5.0kJ/mm
Cold crack susceptibility test of welded joint
| TS (MPa) | Preheating temp. (ºC) | ||
|---|---|---|---|
| 0 | RT | ||
| 1.0kJ/mm | Wire 1 | No-Crack | No-Crack |
| Wire 2 | No-Crack | No-Crack | |
| 1.7kJ/mm | Wire 2 | No-Crack | No-Crack |
| Wire 1 | No-Crack | No-Crack | |
Mechanical properties of base metal
| Grade | Location | YP (MPa) | TS (MPa) | EL (%) | CVN@-40ºC[J] | CTOD@-20ºC [mm] |
|---|---|---|---|---|---|---|
| E500 (50t) | Head | 552 | 658 | 21.3 | 300~450 | 2.23/3.13 /3.19 |
| Tail | 557 | 663 | 22.5 | |||
| Requirement | ≥ 500 | ≥ 0.25 | ||||
Benefits
Application on ship design for low temperature service
Weight reduction by using high strength steel
High weldability and low cold crack susceptibility of steel
