Préchauffage de A106 Gr.B pour SMAW (non-low-hydrogen) — up to 3/4"
Température minimale de préchauffage et entre passes pour A106 Gr.B soudé avec SMAW (non-low-hydrogen) à up to 3/4" d'épaisseur, selon AWS D1.1:2025 Tableau 5.11.
Basé sur AWS D1.1:2025 Tableau 5.11 — chaque valeur tracée à l'article.
Procédé SMAW non bas hydrogène
SMAW (Non-Low-Hydrogen)
Non-low-hydrogen SMAW (E6010/E6011) uses cellulosic electrodes with higher hydrogen potential, assigned to Category A in Table 5.11.
On pipe joints, non-low-hydrogen SMAW root passes with E6010 use the keyhole technique to ensure complete penetration. Pipe rotation (roll welding) is preferred when practical; fixed-position welding requires 5G or 6G qualified procedures. The cellulosic coating generates significant spatter, so adjacent base metal should be protected with anti-spatter compound.
A106 Gr.B
ASTM A106 Grade B covers seamless carbon steel pipe for high-temperature service up to about 750°F, with 35 ksi minimum yield and 60 ksi minimum tensile strength. Produced in sizes from 1/4" through 30" NPS, it is the standard pipe material for power plants, refineries, and process piping where elevated temperature and pressure coexist. Chemistry limits (0.30% max carbon, 0.29-1.06% manganese) give it a weldability profile that matches common structural grades with Category A and B preheat requirements. A106 is exclusively seamless, which eliminates the ERW seam concern present in A53. Grade C (40 ksi yield) exists but Grade B handles the vast majority of process piping service.
Pourquoi ce Préchauffage pour A106 Gr.B avec SMAW
Seamless pipe rated for high-temperature service up to 750°F. At this thickness, SMAW with non-low-hydrogen electrodes places the joint in Category A of Table 5.11. The minimum preheat of 32°F compensates for the higher diffusible hydrogen from cellulosic electrode coatings. The thicker the material, the longer hydrogen takes to escape the heat-affected zone, which is why preheat rises with thickness even for this common grade.
Applications Typiques de A106 Gr.B
Used in boiler steam headers, refinery piping racks, process plant branch connections, heat exchanger nozzle welds, power plant main steam lines, petrochemical reactor feed piping, and high-temperature manifolds. A106 Gr.B butt welds in process piping require joint preparation to B31.1 (power piping) or B31.3 (process piping) depending on service classification. Socket welds on small-bore A106 drain lines and instrument take-offs are common in utility stations, typically 1/2" to 2" NPS. Typical wall thicknesses range from Schedule 40 (0.237" wall on 2" NPS) to Schedule 160 (0.500" wall on 4" NPS) in critical high-energy service. Weld procedure qualification often includes side bend tests and tensile tests specific to the pipe diameter and wall thickness being joined. Field welds at pipe-to-flange connections and valve set-on joints require portable preheating equipment when wall thickness exceeds 1/2".
Pourquoi le Préchauffage est Important à up to 3/4"
Thin material sheds heat quickly, allowing hydrogen to escape the HAZ readily — lowest preheat tier in Table 5.11.
Pourquoi 32°F pour A106 Gr.B ?
Un préchauffage minimum de 32°F (0°C) signifie qu'aucun préchauffage actif n'est nécessaire au-dessus du point de congélation. Le Tableau 5.11 Catégorie A à cette épaisseur attribue le minimum ambiant car A106 Gr.B avec SMAW non bas hydrogène possède une ductilité suffisante et un équivalent carbone assez bas pour que le risque de fissuration par hydrogène soit minimal. Selon la note (a), si la température est inférieure à 32°F, préchauffer le joint à au moins 70°F (20°C) et maintenir pendant le soudage.
Autres Aciers avec SMAW (non-low-hydrogen) à up to 3/4"
A106 Gr.B avec SMAW (non-low-hydrogen)
Essayez Différentes Combinaisons
Utilisez le calculateur interactif de préchauffage pour consulter toute combinaison acier, procédé et épaisseur du D1.1:2025 Tableau 5.11.
Guides de Soudage de A106 Gr.B
Données de référence D1.1:2025. Non affilié à l'AWS.