WLD 150: Welding & Joining Final
___ coupled with riveting increases fatigue strength.
Adhesive bonding
___ occurs when the welder accidentally strikes the electrode on the base metal adjacent to the weld.
Arc strike
___ is a mechanical repair method in which a thinned, pitted, or cracked region of a part is ground away to create a gradual transition with the unaffected surface.
Blend grinding
___ is useful when weld repair is too difficult or unsafe, as in a storage tank that contains flammable vapors.
Blend grinding
___ requires that drillings be taken from the base metal and provides an accurate composition of the base metal.
Chemical analysis
___ magnetization is a concentric magnetic field produced by a straight conductor, such as a piece of wire, carrying an electrical current.
Circular
___ is appropriate for repairing metals that are difficult to weld, such as cast iron.
Cold mechanical repair
The process that converts an adhesive from the applied state to its final solid state is ___.
Curing
___ time is the elapsed time between the application of a developer and the examination of a part.
Developing
The application of a thin, hard, chrome coating to repair minor damage is ___.
Electroplating
___ reduces the fatigue strength of rotating or reciprocating equipment, such as shafts.
Electroplating
___ analysis provides a diagnosis of a technical cause of failure using experience gained from previous failures.
Failure modes and effects
A ferromagnetic material is a material that cannot be magnetized.
False
Cavities only occur on the surface of a weld.
False
Cure time is the total time a penetrant is in contact with a component surface.
False
Demagnetization is the ability of a material to retain a portion of an applied magnetic field after the magnetizing force has been removed.
False
GTAW is used for bronze bearing surfacing weld repair.
False
Gas tungsten arc welding (GTAW) is typically used for surfacing weld repairs on large components.
False
Larger diameter filler metal is preferred to reduce heat input for reducing distortion.
False
Nondestructive testing requires a part to be permanently removed from service.
False
Overlap need not be removed from a weld.
False
Porosity usually consists of long cavities parallel to the root of the weld.
False
Prods used for the prod method of magnetic particle examination must never be crisscrossed.
False
Root cracks are usually easy to detect.
False
Selective plating is the joining of parts with an adhesive placed between the faying (mating) surfaces.
False
Solvent cleaning includes sandblasting, sanding, and wire brushing.
False
The higher the load-bearing cross-sectional area, the higher the stress.
False
Throat cracks are cold cracks that are confined to the edges of a weld.
False
Welding is a mechanical repair method.
False
When performing the magnetic particle examination procedure, demagnetization is not necessary for engine and machine parts, as they typically contain residual magnetization resulting from normal operations.
False
___ is a series of parallel cracks approximately 1/2" apart that occur in brittle deposits as they undergo stress relief.
Linear fracture
___ repair does not involve a significant heat input.
Mechanical
___ crack when exposed to sulfur compounds, such as grease or oil.
Nickel alloys
___ analysis provides a diagnosis of the technical cause of failure using various analytical methods.
Physical failure
___ may be required after weld repair to restore mechanical properties.
Postheating
___ examination does not reveal very narrow discontinuities that are not closely aligned (parallel) to the weld, such as laminations.
Radiographic
___ examination uses X rays and gamma rays to detect discontinuities.
Radiographic
___ is a weld repair that applies surfacing to badly worn shafts by welding snug fitting, semi-circular forms to cover the shaft surface.
Sleeving
___ may be especially susceptible to lamellar tearing.
T-joints
A black light is used with the fluorescent liquid penetrant examination method.
True
A couplant is a liquid substance used between a search unit and a test surface to permit or improve the transmission of ultrasonic energy.
True
A satisfactory adhesive bond requires close contact between the surfaces to be joined.
True
A weld discontinuity is an interruption in the typical structure of a weld.
True
Certain repairs may require the approval of authorized personnel, use of a qualified procedure, and/or preparation of supporting documentation.
True
Cold mechanical repair is commonly used on metals such as gray iron, ductile iron, aluminum, bronze, steel, and fabricated steel sections.
True
Cracks are the most serious discontinuities in weldments.
True
Crater cracks are star-shaped cracks that extend from the crater of a weld to the edge of the weld.
True
Excess weld reinforcement establishes stress concentrations at the junction with the base metal.
True
Failure analysis provides an accurate explanation of the cause of a failure or loss of performance.
True
Hardness is a key indicator of mechanical properties for carbon and alloy steels.
True
Internal weld defects can be detected with radiographic testing equipment.
True
Most codes rely on ASME Section 1X and AWS D1.1 to describe the requirements for qualified welding procedures and welders.
True
Oxide inclusions occur when welding metals that have tenacious surface oxide films, such as stainless steels, aluminum alloys, and titanium alloys.
True
Oxyacetylene welding (OAW) and shielded metal arc welding (SMAW) are often preferred for field weld repairs.
True
Peening is performed prior to preheating the structure to be repaired.
True
Porosity consists of cavity-type discontinuities formed by gas entrapment during solidification.
True
Repair welding is used only if it is economical or if a replacement part is not available.
True
Slag inclusions can occur between passes or at the groove face.
True
The average stress on a weld is in direct proportion to the reduction of the load bearing cross-sectional area caused by a discontinuity.
True
The liquid penetrant examination method is used to find defects in a weld by outlining surface defects.
True
The primary causes of porosity are dirt, rust, and moisture on the surface of the base metal.
True
The weld piece must be magnetized when using the magnetic particle examination method.
True
Tungsten inclusions are particles from a nonconsumable tungsten electrode that enter the weld.
True
Underbead cracks are hydrogen cracks that occur in steels susceptible to hydrogen embrittlement during welding.
True
Undercut produces a stress concentration that reduces impact strength and fatigue resistance.
True
Visual examination is a form of nondestructive testing.
True
Wormholes can be prevented by using methods similar to those used to prevent porosity.
True
A(n) ___ uses a horizontal base line that indicates distance or time, and a vertical deflection from the base line that indicates relative amplitude of the returning signal.
a-scan presentation
A(n) ___ test consists of detecting acoustic signals produced by plastic deformation or crack formation during mechanical loading or thermal stressing of metals.
acoustic
A(n) ___ is a nonrelevant indication that appears on a radiograph.
artifact
Visual examination is used to ___.
check for surface condition
A ___ crack is a crack that develops after solidification is complete.
cold
The thickness of metal required to support a load on a part is the ___.
design thickness
A(n) ___ is a material that is applied to a test surface to accelerate bleedout and enhance the contrast of indications.
developer
The ___ examination method produces an eddy current in the test piece.
electromagnetic
A(n) ___ is a test piece that contains typical discontinuities that demonstrate that calibration equipment is detecting the discontinuities for which the part is being inspected.
equipment calibration standard
In ultrasonic welding, a ___ is one complete reflection of an ultrasonic beam.
full
A(n) ___ point is a point during a fabrication process where inspection and acceptance are required before fabrication can proceed.
hold
Crater cracks are ___ cracks formed by improperly ___ the welding arc in the crater of the weld.
hot; ending
In a(n) ___ test, closed containers are filled with water and a predetermined test pressure is applied.
hydrostatic
A(n) ___ is a device or combination of devices whose demonstrated image determines radiographic quality and sensitivity.
image quality indicator
Cracks are most commonly located by ___ testing.
liquid penetrant
The ___ examination method uses dyes to locate surface defects.
liquid penetrant
Throat cracks typically appear as relatively ___, ___ cracks along the centerline of the weld.
long; straight
Insufficient penetration caused by weld metal running ahead of the arc can be prevented by ___.
lowering the current
The ___ examination method uses a strong magnetizing current and a finely divided powder to detect defects.
magnetic particle
A ___ is a stress-concentrating condition caused by an abrupt change in section thickness or in continuity of a structure.
notch effect
In a(n) ___ test, air is pressurized in a closed vessel to reveal leaks.
pneumatic
Some ___ may be allowed by certain welding codes.
porosity
Porosity caused by excessive moisture on the joint surface can be prevented by ___.
preheating the base metal
A(n) ___ is a permanent, visible image on a recording medium produced by penetrating radiation passing through a material being tested.
radiograph
The ___ examination method uses photographic film or sensitized paper.
radiographic
A ___ wave is a transverse wave that represents wave motion in which the particle oscillation is perpendicular to the direction of wave propagation.
shear
A weld repair method that involves thin sheets of corrosion-resistant material welded to a corroded surface is ___.
sheet lining
A ___ joint contains insufficient adhesive to create an optimum bond.
starved
The ___ examination method uses high-frequency vibrations to locate defects.
ultrasonic
The ___ test is a nondestructive testing procedure.
ultrasonic
Crater cracks are most commonly detected by ___ examination.
visual