A633 Gr.E GMAW 예열 — 3/4" to 1-1/2"
AWS D1.1:2025 표 5.11에 따른 A633 Gr.E의 GMAW 용접 시 3/4" to 1-1/2" 두께에서의 최소 예열 및 층간 온도.
AWS D1.1:2025 표 5.11 기반 — 모든 값이 조항까지 추적됨.
저수소 SMAW, SAW, GMAW 또는 FCAW 공정 (고강도 강재)
GMAW (Gas Metal Arc Welding)
GMAW (MIG) feeds continuous solid wire with shielding gas — an inherently low-hydrogen process assigned to Category B in Table 5.11.
For pressure vessel work, GMAW with ER70S-6 provides excellent deposition rates on long seam welds. Gas backing with argon on back-purged root passes produces a smooth internal weld profile that satisfies radiographic acceptance criteria. Shielding gas purity is critical for vessel code quality; dew point must be below -40°F.
A633 Gr.E
ASTM A633 Grade E is the highest-strength grade in this specification with 60 ksi minimum yield and 80 ksi minimum tensile strength (for plates up to 4”). Produced as normalized and tempered plate, it provides exceptional notch toughness with CVN testing at -60°F (15 ft-lbs transverse). Its higher strength level places it in Category C of Table 5.11, with correspondingly higher preheat requirements than the A/C/D grades. The quenched-and-tempered condition means carbon content is higher (0.22% max) with controlled manganese (1.15-1.50%) and silicon (0.15-0.50%), producing a CE-IIW of approximately 0.44-0.50. Like all Q&T steels, maximum interpass temperature must be respected to avoid degrading the tempered microstructure in the heat-affected zone during multi-pass welding.
GMAW를 사용한 A633 Gr.E의 이 예열 이유
Highest-strength A633 grade at 60 ksi yield requiring Category C preheat. The higher strength level of this steel places it in Category C of Table 5.11, which carries elevated preheat requirements compared to Category B grades. At 150°F minimum with GMAW, the preheat ensures the cooling rate stays slow enough to prevent hydrogen-induced cracking in this higher-hardenability material. Category C steels demand careful attention to interpass temperature control throughout the weld sequence.
A633 Gr.E의 일반적인 용도
Found in heavy-duty crane runway girders for steel mills, offshore jacket legs, polar Class vessels, cold-region bridge main members, large-span roof trusses in Arctic facilities, and load-bearing elements in LNG terminal structures. A633 Gr.E combines 60 ksi yield with excellent low-temperature toughness (CVN testing at -60°F), making it suitable for primary structural members in environments where both high static loads and extreme cold coincide. Procurement lead times for A633 Gr.E plate can be 12-16 weeks due to limited domestic production, and plate availability above 2" thickness may require international sourcing. Repair welding requires the same preheat procedures as original fabrication to maintain the guaranteed toughness properties. Filler metal selection must provide tensile matching (80 ksi minimum) and cold-temperature CVN values that equal or exceed the base metal specification. Weld mockups for offshore and LNG applications typically undergo CTOD or wide-plate testing.
3/4" to 1-1/2"에서 예열이 중요한 이유
Preheat climbs at this range as thicker material slows heat dissipation, trapping hydrogen at crack-susceptible grain boundaries.
A633 Gr.E의 범주 C 예열
표 5.11의 범주 C는 경화성과 잔류 응력의 조합이 높은 예열을 요구하는 고강도 강재에 적용됩니다. 3/4" to 1-1/2"에서 A633 Gr.E의 최소 예열 150°F는 열영향부에서 균열 감수성 마르텐사이트 형성을 방지하기 위해 용접 냉각 속도를 늦춥니다.
3/4" to 1-1/2"에서 GMAW를 사용하는 다른 강재
| 강재 | 범주 | 예열 |
|---|---|---|
| A36 | B | 50°F (10°C) |
| A53 Gr.B | B | 50°F (10°C) |
| A106 Gr.B | B | 50°F (10°C) |
| A709 HPS70W | C | 150°F (65°C) |
A633 Gr.E, GMAW
A633 Gr.E 용접 가이드
D1.1:2025 참조 데이터. AWS와 무관.