Flashcards in NDT methods/weld defects Deck (50)
Inspection, testing and qualification are growing part of _______ in manufacturing and maintenance.
The ______ is the person who begins quality control by being satisfied only with quality welding.
The welder starts the inspection in the process of welding, making immediate adjustment in response to what is being observed in the ______.
Factors that affect quality of weld bead include....
Changing amperage, travel speed, or arc length
Finally, the welder give the completed weld a final _____ to look for any defects that could not be seen while welding.
What are the common methods used in NDE?
VT, MT, Liquid Dye PT, UT, LT (air/water pressure testing)
What is VT?
Visual inspection, a NDT process, examination with the eye. Only able to detect surface discontinuities.
What is the advantage of VT?
Inexpensive equipment and wage, no power required, portable
What is the disadvantage of VT?
requires training/experience, good eye sight, can't detect subsurface defects, no permanent records, human error
What are the 5 steps of VT?
1. Definite procedure
2. Inspection prior to welding
3. Inspection during welding
4. Inspection after welding
5. Mark/make repairs
What are the 7 VT equipment for welding?
Flashlight, magnifying glass, protective lenses, weld gage, hammer/chisel, temperature indicating devices, magnet
What is inspected with VT before welding?
Drawing, position of welds, welding symbols, welding procedure
Specifically paying attention to root face, root gap, bevel angle, and joint/fitup
Proper ____ will prevent discontinuities from occurring.
______ will be used to slow the cooling rate and prevent distortion.
What is inspected with VT during welding?
Electrodes, root pass, subsequent passes, crater formation, weld size/sequence
What is inspected with VT after welding?
Compare weld to standard, weld size, contour/finish, cracks, overlap, undercut, spatter
Testing companies provide an important service because they _____
help manufacturers produce safe and durable goods/structures that consumers can live with.
What are two methods of testing?
Non-destructive and destructive
What are the 4 common NDT methods?
MT, PT, UT, RT
What are the 6 steps of PT?
1 .surface prep
2. penetrant application
3. excess penetrant removal
4. developer application
5. inspection/ evaluation
6. post cleaning
If dye color of defect is deep and not never red, defect is ______.
What is referred to as magnaflux?
Magnetic particle test begins when _____ electric charges is passed between two poles. Force line up until there is a break in these magnetic lines of force.
Direct Current (DC)
In MT, defects appear as a ___ in the lines of force.
The magnetic particles become attracted to the defect, which develops ______ at the edge of the defect, outlining the defect.
north and south poles
What defects are detected with MT?
surface discontinuities, cracks, porosity, slag inclusions, incomplete fusion
What are the disadvantage of MT?
Magnetic materials only, surface roughness may distort field, no permanent record
To enable the formation of a proper magnetic particle pattern for defect indications, the _____ of the defect and magnetic field must be taken into account.
What are the 2 methods of magnetizing the weld zone?
Yoke method, prode method