A992 Preheat for SAW — 3/4" to 1-1/2"
Per AWS D1.1:2025 Table 5.11, the minimum preheat for A992 welded with SAW at 3/4" to 1-1/2" is 50°F (10°C), Category B. Preheat below this raises hydrogen-cracking risk in the heat-affected zone; the same temperature is the minimum interpass limit maintained through the weld.
Built on AWS D1.1:2025 Table 5.11 — every value traced to the clause.
Have a preheat question? Ask Flux
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 with F7A2-EM12K wire/flux delivers the highest deposition rates for flat-position fillet welds on building steel. Typical parameters: 500-700 amps, 28-32 volts, 18-30 IPM travel speed. Flux consumption runs approximately equal to wire consumption by weight. Unfused flux recovery and recycling systems are standard in production shops to control consumable costs.
SAW Tips for Common Structural Steels
For A992 wide-flange shapes (50 ksi yield, Category B), SAW handles long fillet welds on built-up girder and column sections fabricated from A992 plate in heavy industrial and building applications. Web-to-flange fillet seams on built-up A992 plate girders at 550–650 A with F7A2-EM12K achieve 15–25 lb/hr.
Typical values for reference — always verify against your approved WPS and electrode manufacturer data.
Why SAW for A992 at 3/4" to 1-1/2"
Why SAW for A992 at 3/4" to 1-1/2"? SAW delivers 15-40 lb/hr deposition — the highest deposition rate among available processes. Position capability: flat and horizontal only. Suitability: shop only.
A992
ASTM A992 (50 ksi minimum yield, 65 ksi maximum yield, 65 ksi minimum tensile) is the standard specification for W-shapes in building construction — virtually all wide-flange beams and columns in US structural steel buildings are A992. The specification was created in 1998 to address weldability concerns with earlier A36/A572 shapes by imposing tighter chemistry controls: 0.23% max carbon, 0.15% max combined V+Cb+N, and a 0.85 maximum yield-to-tensile ratio to ensure ductile behavior in seismic connections. These controls produce a typical CE-IIW of 0.38-0.44. It falls under Category B in Table 5.11, requiring low-hydrogen welding processes. Most domestic W-shapes are dual-certified A992/A572 Gr.50, with actual mill test yields typically 50-58 ksi. The controlled chemistry makes A992 the most weldable 50 ksi structural shape available.
Why This Preheat for A992 with SAW
Standard W-shape specification for virtually all US building wide-flanges. This steel is prequalified only with low-hydrogen processes under Table 5.11. With SAW, the submerged arc process with granular flux produces controlled hydrogen levels, with flux condition being the primary variable. The 50°F minimum preheat balances the steel’s strength level and carbon equivalent against the hydrogen control provided by SAW. Non-low-hydrogen SMAW is not an option for this grade under D1.1 prequalified WPS.
Typical Applications for A992
The universal W-shape steel for building frames: beam-to-column moment connections, simple shear tabs, column web doubler plates, continuity plates, collector beams in lateral systems, drag struts, transfer beams, and composite deck stud rails. A992 chemistry control (max 0.23% carbon, max 0.15% V-Cb-N) was specifically designed to improve weldability over earlier A36/A572 shapes after the 1994 Northridge earthquake revealed brittle fracture problems in welded steel moment frames. Flange CJP welds in seismic moment frames are the highest-criticality joints in US building construction. The controlled yield-to-tensile ratio (max 0.85) ensures ductile behavior in seismic connections by guaranteeing sufficient strain hardening capacity. Mill test reports for A992 shapes routinely show actual yield strengths of 50-55 ksi, well above the 50 ksi minimum. The weld access hole geometry per AISC 358 is dimensioned specifically for A992 flanges to reduce stress concentrations at the CJP weld termination.
Why Preheat Matters at 3/4" to 1-1/2"
Preheat climbs at this range as thicker material slows heat dissipation, trapping hydrogen at crack-susceptible grain boundaries.
Other Steels with SAW at 3/4" to 1-1/2"
| Steel | Category | Preheat |
|---|---|---|
| A1066 Gr.50 | B | 50°F (10°C) |
| A1066 Gr.60/65 | C | 150°F (65°C) |
| A1066 Gr.70 | C | 150°F (65°C) |
| A633 Gr.E | C | 150°F (65°C) |
A992 with SAW
Try Different Combinations
Use the interactive preheat calculator to look up any steel, process, and thickness combination from D1.1:2025 Table 5.11.
A992 Welding Guides
Primary sources
D1.1:2025 reference data. Not affiliated with AWS.
Application context
A992 plate or W-shape members in the 3/4 to 1-1/2 inch range with SAW is the high-deposition shop combination for AISC primary structural fabrication — heavy beam-flange-to-web welds on built-up plate girders, splice plates on W-shape moment-frame members, continuity plates at column-to-girder joints, and primary connection plates at heavy moment-frame intersections where the SAW process matches the production volume of AISC moment-frame fabrication.
Pre-weld notes
Three constraints layer at this combination. First, the 50°F preheat floor needs active verification per Clause 7.6 — the heated zone must extend at least twice the base-metal thickness from the welding point. Second, A992 sits in Table 5.6 Group II with a 50 ksi minimum yield, requiring SAW electrode-flux combination from Table 5.7 Group II (F7XX-EXXX, F7XX-ECXXX, F7XX-E(C)XXX-A1, A2, A4, Ni1, Ni2 under A5.17/A5.17M and A5.23/A5.23M). Third, flux conditioning per Clause 7.3.3 with reclamation rules per Clause 7.3.3.3 — the contractor must have a system for collecting unmelted flux and welding such that flux composition stays relatively constant.
What a CWI verifies
A CWI on A992 SAW mid-thickness shop work verifies (1) preheat at perimeter and samples mid-joint with a contact pyrometer after the first pass group, (2) electrode-flux combination against Table 5.7 Group II, (3) flux dryness and the reclamation system per Clause 7.3.3, and (4) current and layer width against Table 5.2 prequalified SAW limits for the specific electrode configuration. AISC seismic moment-frame work commonly carries CVN testing requirements under project documents that elevate the WPS to qualified rather than prequalified, with Table 6.6 + Table 6.8 essential-variable controls layered on top.