Flux-Cored Arc Welding Machinery's Handbook, 31st Edition
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Table 8. Deposition Rates for Vertical Up Welding with All-Position, Flux-Cored Electrodes (ET71T-1) Electrode Diameter Typical Deposition Rate Range Average Deposition Rate inch (mm) lb/h (kg/h) lb/h (kg/h) 0.035 (1) 2.7–6.5 (1.2–3) 5 (2.3) 0.045 (1.2) 5–11 (2.3–5) 8 (3.6) 0.052 (1.4) 4–8 (1.8–3.6) 6.5 (3) 0.062 (1.6) 4–11 (1.8–5) 8.5 (4) Table 9. Average Deposition Rates for Flat and Horizontal Welds
Cost-Effective Current Range
Optimum Current (amps)
Electrode Size inch (mm) 0.045 (1.2) 0.052 (1.4) 0.062 (1.6) 0.045 (1.2) 0.035 (1) 0.052 (1.4) 0.062 (1.6)
Deposition Rate
Process
(amps) 250–350 300–400 350–470 375–500 225–310 260–350 300–400
lb/h
(kg/h)
285 385 410 450 300 310 340 460
9
(4)
13 11 17 14 15 15 17
(5.9)
GMAW spray transfer
(5)
(7.7) (6.4) (6.8) (6.8)
FCAW (7.7) The average deposition rates of pulsed GMAW and FCAW for vertical up welds are sim ilar for applications where the steel thickness is 1 ∕ 8 in. (3.2 mm) or less. On steels thicker than 1 ∕ 3 ∕ 32 (2.4) 380–560 8 in., where the current may be increased, and larger-diameter all-position FCAW electrodes may be used, deposition rates will be much greater than with pulsed GMAW. Compared with GMAW electrodes for pulsed welding, FCAW all-position electrodes require less costly equipment, less welding skill, and have potential for increased weld fusion with less porosity than with GMAW pulsed techniques. Electrode Diameters and Deposition Rates.— A cost-effective welding shop can achieve deposition rates on flat and horizontal welds of 12 to 15 lb/h (5 to 7 kg/h) with both the GMAW 0.045-in. wire and the 0.062-in. flux-cored wire electrodes, without welder dis - comfort, and with welds of consistent quality. The first consideration in selecting the optimum size of gas-shielded FCAW E70T-X electrode for manual flat and horizontal welds on steels thicker than 1 ∕ 4 in. (6.4 mm) is the current requirements needed to achieve deposition rates of 12 to 15 lb/h (5 to 7 kg/h). Large-size electrodes of 3 ∕ 32 -in. (2.4-mm) diameter require 500 amps or more to attain optimum deposition rates. These 3 ∕ 32 -in. diameter electrodes are often used with power sources in the 300–400 amp range, but even when the power source provides 500 to 600 amps, welding is often performed at the low end of the electrode’s current requirements. With the large, 3 ∕ 32 -in. diameter electrodes, welder appeal is low, smoke is often excessive, and deposition rates are often only comparable with smaller, easier-to-operate FCAW electrodes. Typical deposition rates for flat and horizontal welds with various electrode sizes and weld settings are shown in Table 9. In connection with this table, it may be noted that high deposition rates in welding steel plate thicker than 1 ∕ 4 in. require use of currents above the minimum shown for the various sizes of electrodes. The optimum current requirements for the most popular electrode sizes indicate that a 450-amp power source is the most suitable for welding steel of more than 1 ∕ 4 in. thickness. The two most cost-effective and
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