weld faults Flashcards
- Leg size
- Root penetration
- theoretical throat
- toe of weld
- face of weld
- depth of fusion
undercut on vertical leg, overlap on horizontal leg.
insufficient leg size on vertical leg, undercut on horizontal leg.
insufficient throat and overlap on horizontal leg.
profile acceptance
- Depth of penetration
- root face
- root opening
- reinforcement
- weld throat
- toe of weld
a. undercut, porosity
b. defect free - acceptance profile
c. insufficient throat, incomplete fusion
Who is responsible for ensuring that proper welding procedures are carried out?
The welding supervisor and the welding engineer, if applicable.
Which CWB approved documents contain information that is used to produce acceptable welds?
Welding procedure data sheets and the related welding procedure specification.
Which consumables require special handling?
All basic type electrodes
(EXXXX6 or EXXXX8).
What can cause thick and/or a highly restrained plate to crack when it is welded?
Inadequate preheat temperatures, small welding passes.
List five items related to welding that
should be on detail drawings.
1. _________ _
2. _________ _
3. _________ _
4. ———-
5. ———-
a. material type
b. material thickness
c. joint type
d. weld size
e. weld locations
f. weld length
g. bevel angle
h. depth of preparation
i. root face root opening
J. postweld heat treatment requirements
k. NOT requirements
When welding with the FCAW
and GMAW processes, what are some of the
parameters that must be verified?
1. ———-
2. _________ _
3. _________ _
4. _________ _
5. ———
a. electrode designation
b. electrode diameter
c. electrode polarity
d. shielding gas composition
e. shielding gas flow rate
f. purging gas
g. purging gas flow rate
h. wire feed speed
i. voltage
j. arc travel speed
k. tip to work distance
I. number or passes or layers
m. preheat temperature
What happens if the slag is not
removed between the passes?
It invariably leads to the slag being
trapped between the passes.
Why must the finished weld be cleaned of all slag?
The slag must be removed in order to visually inspect the weld.
List some nondestructive inspection methods.
a. Liquid penetrant
b. Magnetic particle
c. Radiographic
d. Ultrasonic
e. Visual inspection
What type of discontinuities can be detected with the liquid penetrant inspection method?
Discontinuities, such as surface cracks
and porosity, that are open to the surface
of the material.
What type of discontinuities
can be detected with the magnetic particle
inspection method?
Discontinuities such as cracks, porosity,
slag inclusions, and incomplete fusion in
magnetic mate rials, that are open to or just
below the surface.
Give some causes of incomplete fusion.
a. Poor joint design
b. Incorrect size and type of electrode
c. Incorrect voltage and current settings
d. Electrode manipulation
e. Welding on contaminated material
Why is it important to have proper fitup of a joint?
To reduce the amount of welding that
is required and, therefore, control the cost of
production. Good fit-up will also reduce the
possibility of having certain defects in the weld.
List some destructive testing methods.
a. Tensile test
b. Bend test
c. Impact test
Which discontinuity is considered to be the most serious?
A crack is considered to be the most serious defect. It takes very little energy to keep a crack growth until, eventually, the product fails.
List some of the problems that can
arise from an arc strike.
a. A hardened area at point of contact.
b. Cracking can occur in area of arc strike.
Which of the following can cause a
thick or highly restrained plate to crack
when it is welded?
a. inadequate preheat temperature
b. inadequate postheat temperature
c. proper sequence of welding
d. low restrained welds
a. inadequate preheat temperature
