Machinery's Handbook, 31st Edition
Gas Metal Arc Welding 1583 As indicated at the lower left in Fig. 3, the current range for 0.062-in. (1.6-mm) elec trodes is narrow and most welds are made in the range of 360 to 420 amps, or between the ten and eleven o’clock positions on the wire feed control unit for 210 to 280 in/min (90 to 120 mm/s). The quadrants at the lower center and lower right in Fig. 3 show deposition rates in lb/h and kg/h for 0.045-in. (1.2-mm) and 0.062-in. (1.6-mm) diameter electrodes. Some optimum settings for GMAW welding with a mixture of argon + 15 to 20 percent CO 2 gases are given in Table 5.
Optimum Settings
28 270
26 300
350 420
280 350 420
280 350 420
IPM
490
490
490
210
IPM
IPM
560
560
560
0.045 in. 1.2 mm
0.045 in. 1.2 mm
0.045 in. 1.2 mm
630
630
630
700
700
700
Volts
Volts
Volts
Amps
Amps
Amps
A Ar+ 15–20% CO 2
C 75% Ar+ 25% CO 2
B Ar-Oxy 95% Ar+ 5% Oxy
Optimum Settings
9.5 4.3
8 18
36 450
kg/h
Amps
lb/h
Volts
lb/h
kg/h
280 350 420
280 350 420
Stable Spray
210
210
0.062 in. 1.6 mm
140
140
Deposition Rates 0.062 in. 1.6 mm
Deposition Rates 0.045 in. 1.2 mm
85% Ar 15% CO 2
Fig. 3. GMAW Spray Transfer Parameters for Various Electrodes and Gases Table 5. Optimum Settings for GMAW with Argon + 15–20 percent CO 2 Diameters Mode Wire Feed Rates Amps Volts inch mm in/min m/min 0.035 1.0 short circuit 210 5.3 140 17 spray transfer 560 14.2 280 29–30 0.045 1.2 short circuit 210 5.3 190 18 spray transfer 420 10.7 380 30–31 0.052 1.4 spray transfer 280 7.1 370 31–32 0.062 1.6 spray transfer 280 7.1 410 31–32 Note: If argon + oxygen gas mixtures are used, voltage should be lowered by 1 to 4 volts for the spray transfer mode. The faster the weld travel speed, the lower the voltage required. Spray Transfer Voltage.— The usual setting for spray transfer welding with commonly used electrode diameters is between 25 and 35 volts (see Fig. 4A). To set the optimum volt age for GMAW spray transfer, set the voltage initially so that it is too high, usually between
Copyright 2020, Industrial Press, Inc.
ebooks.industrialpress.com
Made with FlippingBook - Share PDF online