A1066 Gr.60/65のSAW用予熱 — over 2-1/2"
A1066 Gr.60/65をSAWで板厚over 2-1/2"で溶接する場合の最低予熱およびパス間温度。AWS D1.1:2025 表5.11に基づく。
AWS D1.1:2025 表5.11に基づく — すべての値は条項に追跡可能。
低水素SMAW、SAW、GMAW、またはFCAWプロセス(高強度鋼)
SAW (Submerged Arc Welding)
SAW submerges the arc beneath granular flux for highest deposition rates, flat/horizontal only. Category B in Table 5.11.
SAW on high-strength plate requires careful selection of wire-flux combinations to meet both tensile matching and toughness requirements. F8A4-EA2 or similar high-performance combinations serve Category C steels. Heat input control is particularly important on TMCP grades because SAW naturally deposits high heat input due to the deeply penetrating arc.
SAW Tips for High-Strength and TMCP Steels
For A1066 Grades 60/65 HSLA plate (60–65 ksi yield, Category C or H8 Category E), SAW with F8A4-EA2 provides tensile matching at 80 ksi minimum. H8 Category E path (50°F up to 1", 120°F above) requires H8-certified flux — verify lot certificate, not just wire. On offshore monopile transition piece seams (plate to 4" thick), tandem SAW with two wires.
Typical values for reference — always verify against your approved WPS and electrode manufacturer data.
Why SAW for A1066 Gr.60/65 at over 2-1/2"
Why SAW for A1066 Gr.60/65 at over 2-1/2"? SAW delivers 15-40 lb/hr deposition — the highest deposition rate among available processes. Position capability: flat and horizontal only. Suitability: shop only.
A1066 Gr.60/65
ASTM A1066 Grades 60 (60 ksi yield, 75 ksi tensile) and 65 (65 ksi yield, 80 ksi tensile) are higher-strength low-alloy plates used in bridges and structural applications requiring both strength and toughness at sub-zero temperatures. They fall under Category C for standard low-hydrogen processes, reflecting their higher CE-IIW of approximately 0.44-0.50, and qualify for Category E reduced preheat (50°F up to 1”, 120°F above 1”) with H8-certified consumables. The dual-path preheat option (Category C standard vs. Category E with H8) gives fabricators economic flexibility — choosing H8 consumables adds a small material premium but can save significant preheating time and fuel cost on thick-section joints. Both grades are produced in plate thicknesses up to 6" and require ASTM supplementary toughness requirements for bridge or offshore service.
A1066 Gr.60/65とSAWでこの予熱が必要な理由
Higher-strength 60/65 ksi HSLA plate for bridges with H8 preheat option. 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 300°F minimum with SAW, the submerged arc process with granular flux produces controlled hydrogen levels, with flux condition being the primary variable, but the preheat must still ensure the cooling rate stays slow enough to prevent hydrogen-induced cracking in this higher-hardenability material.
A1066 Gr.60/65の代表的な適用例
Specified for long-span bridge plate girder flanges, cable-stayed deck plates, offshore wind monopile transition pieces, heavy-wall tubular joints in jacket structures, and demanding structural applications requiring both 60+ ksi yield and sub-zero toughness. The H8 preheat reduction to Category E (50°F up to 1", 120°F above 1") makes these grades economically competitive for heavy plate fabrication where heating thick sections adds hours to the welding cycle. Plate thicknesses in offshore monopile transition pieces can reach 4" or more, with individual circumferential seams requiring sustained preheating over several hours. The combination of high strength, toughness, and H8 preheat eligibility positions A1066 Gr.60/65 as a premium alternative to conventional plate grades in demanding offshore environments. Filler metal selection must achieve tensile matching (80+ ksi) while meeting CVN requirements at the service temperature — typically -4°F to -40°F for North Sea and US Gulf offshore installations.
over 2-1/2"で予熱が重要な理由
The heaviest sections demand the highest preheat in Table 5.11. Multi-pass sequences require maintaining interpass temperature throughout.
A1066 Gr.60/65のカテゴリーC予熱
表5.11のカテゴリーCは、焼入性と残留応力の組み合わせにより高い予熱が必要な高強度鋼に適用されます。over 2-1/2"のA1066 Gr.60/65において、300°Fの最低予熱は溶接冷却速度を遅くし、熱影響部での割れ感受性マルテンサイトの生成を防ぎます。拘束された継手の多パス溶接では、パス間温度をこの最低値以上に維持することが特に重要です。
SAWとover 2-1/2"における他の鋼材
A1066 Gr.60/65とSAW
A1066 Gr.60/65溶接ガイド
D1.1:2025参考データ。AWSとの提携なし。