Calculadora de pré-aquecimento de vergalhões D1.4
Consulte o pré-aquecimento mínimo e a temperatura de interpasse para soldar barras de aço de reforço conforme AWS D1.4/D1.4M:2018 Tabela 7.2. Informe o carbono equivalente (CE) e selecione o tamanho da barra.
Use AWS D1.4 Tabela 7.2 para consultar o pré-aquecimento de vergalhões a partir do carbono equivalente e do tamanho da barra. A calculadora mantém as fórmulas de CE da D1.4 separadas das premissas de CE IIW do aço estrutural e sinaliza as notas sobre metal base frio, resfriamento natural e pré-aquecimento mais alto do aço estrutural para verificação na oficina antes de soldar.
Baseado na AWS D1.4:2018 Tabela 7.2 — o pré-aquecimento de vergalhões é rastreado até a cláusula.
Preheat Lookup
Applies to SMAW with Baixo Hidrogênio electrodes, GMAW, FCAW, and GTAW. All processes Compartilhar the same Requisitos.
Per AWS D1.4:2018
Clause 7.2.1: minimum preheat and interpass temperatures are in accordance withTable 7.2, using the highest CE fromClause 1.5.4.
D1.4 Table 7.2 Preheat Lookup
SMAW with low-hydrogen electrodes, GMAW, FCAW, or GTAW. When welding rebar to Aço estrutural, also check D1.1 preheat requirements and use the higher value.
Enter carbon equivalent and bar size above to see the applicable preheat result.
D1.4 Preheat Requirements
Rebar to structural steel: When steel reinforcing bars are welded to structural steel, the preheat requirements of D1.1 also apply. Use the higher preheat requirement of D1.4 Table 7.2 and D1.1 Table 5.11. Extreme caution is needed when welding rebar to quenched and tempered steels. Ao unir barras a aço estrutural temperado e revenido, cumpra os requisitos de pré-aquecimento de ambos os materiais. Se ambos não puderem ser atendidos, não una os materiais por soldagem.
Quando o pré-aquecimento for necessário, aqueça toda a seção transversal da barra até a temperatura mínima especificada por pelo menos 6 in [150 mm] de cada lado da junta. Mantenha temperaturas de pré-aquecimento e interpasse suficientes para evitar trincas.
Cold weather: When the Metal de Base is below 32°F (0°C), preheat to at least 70°F (20°C) and maintain during welding.
Cooling: After welding, bars must cool naturally to ambient Temperatura. Accelerated cooling is prohibited.
Carbon equivalent: For bars other than ASTM A706/A706M, use CE = C + Mn/6. For ASTM A706/A706M, use CE = C + Mn/6 + Cu/40 + Ni/20 + Cr/10 - Mo/50 - V/10. When chemical composition is not available, see D1.4 Clause 1.5.4. Use our Carbon Equivalent Calculator to compute CE from MTR data.
D1.4 Rebar Preheat FAQ
AWS D1.4:2018 Clause 1.5.4 uses two formulas, not the IIW formula. For bars other than ASTM A706/A706M, CE = C + Mn/6. For ASTM A706/A706M, CE = C + Mn/6 + Cu/40 + Ni/20 + Cr/10 - Mo/50 - V/10. Table 7.2 then maps CE and bar size to preheat.
Table 7.2 covers SMAW with low-hydrogen electrodes, GMAW, FCAW, and GTAW. All four processes share the same preheat requirements — unlike D1.1, D1.4 does not differentiate preheat by welding process. Non-low-hydrogen SMAW is not addressed in this table.
When reinforcing bars are welded to structural steel, both D1.4 Table 7.2 and D1.1 Table 5.11 apply. Use the higher preheat requirement of the two tables. If the structural steel requires a higher preheat than the rebar, that higher temperature governs. Extreme caution is needed when welding rebar to quenched and tempered steels.
When Table 7.2 shows 'none', no minimum preheat temperature is required for that combination. However, if the base metal temperature is below 32°F (0°C), you must still preheat to at least 70°F (20°C) and maintain that temperature during welding. After welding, bars must cool naturally — accelerated cooling is prohibited.