Total resistance in welding is composed of: (i) Resistance of electrode (ii) Contact resistance between electrode and workpiece (iii) Contact resistance between two workpiece plates (iv) Resistance of workpiece
(i), (ii), (iii) and (iv)
(ii), (iii) and (iv)
(ii) and (iv)
(i)
The material used for making the two electrodes of resistance welding are mainly
Copper
Aluminum
Steel
Nickel
If 20 amperes of current is flowing in a wire for 1 minute of time having a resistance of 1000 ohm. Then the amount of heat generated in resistance welding will be (in kilo joules) equal to
24000
240000
24000000
2400
In resistance spot welding process the Time between pressure application and weld is called
Hold Time
Off Time
Squeeze Time
Weld Time
Which group of electrodes are best suitable for high temperatures during resistance spot welding?
Group A, Class I, II, III, IV, and V copper alloys
Group B, Class 10, 11, 12, 13, and 14 refractory alloys
Group A or Group B electrodes
Both Group A and Group B electrodes
Which of the following is true for seam welding?
The electrodes are usually made from copper
The electrodes are often disc shaped
It is a resistance welding
All of the above
In which friction welding (FW) process the rotational speed remains constant until the brake is applied?
Continuous drive
Inertia drive
Both (a) and (b)
Neither (a) and (b)
Which of the following formula generally used for low carbon steel?
Electrode tip diameter = 0.40’’ + 8t, t = thickness in inches
Electrode tip diameter = 0.30’’ + 6t, t = thickness in inches
Electrode tip diameter = 0.10’’ + 2t, t = thickness in inches
Electrode tip diameter = 0.20’’ + 4t, t = thickness in inches
A welding which is produced from overlapping spots made at the point of contact created by two opposing wheels, with timed current pulses or groups of pulses producing each spot is called
Resistance Upset welding
Resistance Lap welding
Resistance Butt welding
Resistance Seam welding
In which type of resistance welding, capacitor-discharge is used?
Percussion welding
Upset welding
Seam welding
Lap welding