120102g Distortion

Question 1

Temperature, expressed in °F or °C, refers to the measure of the:
a) intensity of energy.
b) amount of energy.
c) volume of energy.
d) quantity of energy.

Answer 1

a) intensity of energy.

Question 2

The term heat expresses:
a) quantity.
b) degrees.
c) temperature.
d) intensity.

Answer 2

a) quantity.

Question 3

Which is a common cause of distortion?
a) using specified welding procedures
b) unequal heating and cooling of welds
c) free expansion and contraction
d) equal heating and cooling of welds

Answer 3

b) unequal heating and cooling of welds

Question 4

When heated evenly and without restraint, in which direction does metal expand?
a) transversely (across)
b) longitudinally (lengthwise)
c) volumetrically (in all directions)
d) only upwards and downwards

Answer 4

c) volumetrically (in all directions)

Question 5

Transitional expansion occurs when a metal changes from:
a) a solid state to a liquid state.
b) one crystalline structure to another.
c) one colour to another.
d) a liquid state to a solid state.

Answer 5

b) one crystalline structure to another.

Question 6

Which type of distortion results from shrinkage across the weld that tends to pull a member of a Tee joint toward the welded side?
a) transitional distortion
b) transverse distortion
c) longitudinal distortion
d) angular distortion

Answer 6

d) angular distortion

Question 7

Which type of distortion results in an overall reduction in the length of the weld?
a) transitional distortion
b) transverse distortion
c) longitudinal distortion
d) angular distortion

Answer 7

c) longitudinal distortion

Question 8

Which type of distortion refers to the tendency (in butt joints) for the plates to draw together down the length of the joint as you are welding?
a) transitional distortion
b) transverse distortion
c) longitudinal distortion
d) angular distortion

Answer 8

b) transverse distortion

Question 9

What causes angular distortion in a Vee groove weld if the plates are free to move?
a) the non-uniform contraction of the weld metal
b) the rapid cooling of the weld metal
c) making tacks too small on the ends of the plate
d) the weld metal expanding when it cools

Answer 9

a) the non-uniform contraction of the weld metal

Question 10

What is the primary cause of distortion created from longitudinal shrinkage?
a) welding at a slow rate of speed
b) making tacks too small at the ends
c) a weld made using the wrong polarity
d) weld beads contracting upon cooling

Answer 10

d) weld beads contracting upon cooling

Question 11

What welding variable is more likely to have the plates of a butt joint draw together causing transverse distortion?
a) welding at a faster rate
b) using straight polarity
c) using reverse polarity
d) welding at a slower rate

Answer 11

d) welding at a slower rate

Question 12

What is one method you can use to correct angular distortion on butt joints?
a) Weld with one pass.
b) Weld with many passes.
c) Weld on both sides.
d) Allow the plates to move freely.

Answer 12

c) Weld on both sides.

Question 13

How can you reduce longitudinal distortion?
a) Keep weld reinforcement to a minimum.
b) Weld on one side of the joint only.
c) Use slow welding speeds.
d) Avoid back stepping.

Answer 13

a) Keep weld reinforcement to a minimum.

Question 14

What is one method to reduce transverse distortion?
a) Use a slow deposition rate.
b) Use a fast deposition rate.
c) Align the plates so that the space between them decreases along the length of the weld.
d) Before welding, set the plates closer together than you need for the finished weld.

Answer 14

b) Use a fast deposition rate.

Question 15

What is a disadvantage to rigid clamping and fixturing?
a) Set-up time slows down production.
b) Some distortion can occur after releasing the clamping.
c) Rigid clamping and fixturing material is expensive.
d) This method cannot be used on objects with square corners.

Answer 15

b) Some distortion can occur after releasing the clamping.

Question 16

What is one advantage of a jigging device?
a) It prevents shrinkage of parts.
b) It allows for welding in all positions and reduces productivity.
c) It maintains accuracy of the finished product.
d) It prevents uneven contraction.

Answer 16

c) It maintains accuracy of the finished product.

Question 17

Pieces of metal placed on either side of the joint that absorb the heat of the weld and help prevent distortion are called:
a) plate clamps.
b) weld positioners.
c) chill strips.
d) back-up bars.

Answer 17

c) chill strips.

Question 18

What is the purpose of balancing welds around the neutral axis of a worn shaft?
a) to equalize the contraction stresses of the welds
b) to increase the heat buildup into the shaft
c) to get a more uniform weld buildup
d) to allow the use of larger electrodes

Answer 18

a) to equalize the contraction stresses of the welds

Question 19

How can you help control distortion when welding light gauge metal?
a) Increase the preheat temperature.
b) Decrease your welding speed.
c) Increase the number of tacks.
d) Maintain a 90° electrode inclination.

Answer 19

c) Increase the number of tacks.

Question 20

Which fillet weld application produces the greatest amount of distortion?
a) staggered intermittent fillet welds
b) a small fillet weld with a concave profile
c) fillet welds produced with one continuous pass
d) multi-pass fillet welds with a convex profile

Answer 20

d) multi-pass fillet welds with a convex profile

Question 21

What is one characteristic of a good welding design?
a) It uses many rapid changes in cross-section.
b) It uses formed or rolled sections.
c) It uses as many small pieces as possible.
d) It uses vertical and overhead position welds as much as possible.

Answer 21

b) It uses formed or rolled sections.

Question 22

When several plates must be welded together with butt joints, what is the best weld sequence to control distortion?
a) Weld from the outside edges and toward the centre in both directions.
b) Weld from the corners and toward the centre in all directions.
c) Weld in concentric circles toward the centre without back stepping.
d) Weld from the centre and toward the outside in both directions.

Answer 22

d) Weld from the centre and toward the outside in both directions.

Question 23

What is the advantage of using sub-assemblies?
a) They provide for more welds in the flat position.
b) They provide for more welds in vertical and overhead positions.
c) Jigs and skeleton frames are not necessary.
d) They eliminate the need for formed or rolled sections.

Answer 23

a) They provide for more welds in the flat position.