gmaw

a a a a

d d d d

c c c c c c c c

d d d d d d d d d d d d b b b b a

1 The inclusion of an inductance in the welding circuit when using MIG/MAG welding process is to: Control the rate of spatter in the dip transfer mode. a It enables the welder to weld in position with the spray transfer mode. b It allows for thicker filler wires to be used (2.6-3.6mm diameter). c It allows full control over droplet size in the spray transfer mode. d 2 When welding with the MIG welding process using pure argon as the shielding gas on carbon steel, which of the following problems are likely to occur? Copper inclusions and excessive cap heights. a Excessive root penetration and porosity. b Slag inclusions and crater pipe. c Lack of fusion and poor cap profiles. d 3 When considering the MIG/MAG welding process which of the following metal transfer modes would be the best suited to the welding of thick plates over 25 mm, flat welding position. Dip transfer. a Pulse transfer. b Spray transfer. c Globular transfer. d 4 When calibrating a mechanised MAG welding plant, which of the following applies (WFS = Wire feed speed)? Check – WFS, current, volts and wire diameter. a Check – WFS, joint set-up, gas flow rate and WFS. b Check – Gas flow rate, stick out length, WFS and current. c All of the above. d 5 When welding with the MIG welding process using pure argon as the shielding gas on carbon steel, which of the following problems are likely to occur? Copper inclusions and excessive cap heights. a Excessive root penetration and porosity. b Slag inclusions and crater pipe. c Lack of fusion and poor cap profiles. d 6 For GMAW the burn-off rate of the wire is directly related to … the stick-out length a wire feed speed b the arc voltage c the travel speed d 7 MIG/MAG welding has a tendency to give lack of sidewall fusion when … Spray transfer conditions are used a 100% CO2 shielding gas is used b pulse current is used c dip transfer conditions are used d 8 The dip transfer mode (or short circuiting mode) of metal transfer used for MIG/MAG welding is characterised by … giving deep penetration a being suitable for positional welding b giving low spatter c All of the above. d 9 Spray Mode of Transfer is associated with GMAW process. But it is limited to PA. PB and PC position a

a a a

b c d

Gives high deposition rate Produced a lot of spatter All of the above.