Exam 30: Testing and Inspecting Welds

Many acceptable products may have welds that contain defects. But no products may have welds that contain discontinuities.

To prevent undercutting, you can weld in the flat position by using multiple instead of single passes, change the shield gas, and improve manipulative techniques to fill the removed base metal along the toe of the weld bead.

____ occurs in fusion welds when weld deposits are larger than the joint is conditioned to accept.

A lack of fusion between the filler metal and previously deposited weld metal is called ____________________.

A discontinuity becomes a defect when the discontinuity becomes so large or when there are so many small discontinuities that the weld is not acceptable under the standards for the code for that product.

The three methods of testing welded butt joints are (1) the nick-break test, (2) the guided-bend test, and (3) the free-bend test.

____________________ inspection uses finely divided ferromagnetic particles (powder) to indicate defects open to the surface or just below the surface on magnetic materials.

The majority of welds receive only visual inspection.

____ porosity is most often caused by improper starting and stopping techniques.

____________________ methods, except for hydrostatic testing, result in the product being destroyed.

A cylindrical porosity is called a(n) ____________________, and it is the most likely type of porosity to reach the weld surface and be seen.

Ultrasonic inspection (UT) is a nondestructive test. This method is based upon magnetic induction in which a magnetic field induces eddy currents within the material being tested.

Tensile testing is used to determine how well a weld can resist repeated fluctuating stresses or cyclic loading.

____ results from gas that was dissolved in the molten weld pool, forming bubbles that are trapped as the metal cools to become solid.

____ is the lack of coalescence between the molten filler metal and previously deposited filler metal and/or the base metal.

Although not visible, the development of inclusions can be expected if prior welds were improperly cleaned or had a poor contour.

Lamellar tears differ from lamination because they are more extensive and involve thicker layers of nonmetallic contaminants.

____ occurs when the depth that the weld penetrates the joint is less than that needed to fuse through the plate or into the preceding weld.

One common test used to determine the impact capability of a weld is the ____ test in which a notched specimen is struck by an anvil mounted on a pendulum.

____ on a groove weld appears when the weld metal deposited is inadequate to bring the weld's face or root surfaces to a level equal to that of the original plane or plate surface.