Calcolatore di preriscaldo per barre d’armatura D1.4
Consulta il preriscaldo minimo e la temperatura di interpass per la saldatura delle barre d’acciaio da armatura secondo AWS D1.4/D1.4M:2018 Tabella 7.2. Inserisci il carbonio equivalente (CE) e seleziona il diametro della barra.
Usa AWS D1.4 Tabella 7.2 per ricavare il preriscaldo delle barre d’armatura dal carbonio equivalente e dal diametro della barra. Il calcolatore tiene separate le formule di CE della D1.4 dalle ipotesi di CE IIW per l’acciaio strutturale e segnala le note su metallo base freddo, raffreddamento naturale e preriscaldo più elevato dell’acciaio strutturale da verificare in officina prima della saldatura.
Basato su AWS D1.4:2018 Tabella 7.2 — il preriscaldo delle barre è riportato alla clausola.
Preheat Lookup
Applies to SMAW with Basso Idrogeno electrodes, GMAW, FCAW, and GTAW. All processes Condividi the same Requisiti.
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 structural steel, 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. Per unire barre ad acciaio strutturale bonificato, soddisfare i requisiti di preriscaldo di entrambi i materiali. Se ciò non è possibile, non unire i materiali mediante saldatura.
Quando è richiesto il preriscaldo, portare tutta la sezione della barra almeno alla temperatura minima prescritta per almeno 6 in [150 mm] su ciascun lato del giunto. Mantenere temperature di preriscaldo e interpass sufficienti a prevenire cricche.
Cold weather: When the Metallo 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.