CWI NDE Methods and Symbols Questions and Answers

Question 1

A welding blueprint has a symbol in the tail of the reference line that reads 'UT'. This indicates that the weld requires which of the following?

Accepted Answer

Ultrasonic Testing to detect internal and sub-surface discontinuities.

Answer

According to AWS A2.4, Standard Symbols for Welding, Brazing, and Nondestructive Examination, letter designations are used in the tail of the welding symbol to specify the NDE method. 'UT' is the standard abbreviation for Ultrasonic Testing, which uses high-frequency sound waves to detect internal flaws.

Question 2

A CWI is reviewing a welding procedure for a critical application on a non-ferromagnetic stainless steel component. The procedure calls for an NDE method to detect fine surface-breaking cracks. Which of the following methods would be most appropriate and effective for this specific scenario?

Accepted Answer

Dye Penetrant Testing (PT)

Answer

Dye Penetrant Testing (PT) is a highly effective method for detecting surface-breaking defects like fine cracks and porosity in non-ferromagnetic materials. Magnetic Particle Testing (MT) is not suitable because the material is non-ferromagnetic. While VT is always performed, PT is more sensitive to very fine cracks. RT is primarily used for detecting internal, volumetric defects, not fine surface cracks.

Question 3

On a welding symbol, where is the information specifying the length and number of NDE examinations to be performed typically placed?

Accepted Answer

In the tail of the reference line

Answer

The tail of the welding symbol is used to convey supplementary information, which includes specifications for nondestructive examination such as the method to be used, the length to be examined, and the number of tests required.

Question 4

Which of the following NDE methods has no arrow side or other side significance when its symbol is placed on the reference line of a welding symbol?

Accepted Answer

Radiographic Testing (RT)

Answer

Nondestructive examination methods that inspect the full volume of the weld, such as Radiographic Testing (RT) and Ultrasonic Testing (UT), do not have arrow side or other side significance. The examination covers the entire joint. Therefore, the symbol is placed directly on the reference line. Methods that inspect surfaces, like VT, MT, and PT, have arrow side/other side significance.

Question 5

A fabrication drawing for a carbon steel pressure vessel shows the NDE symbol 'MT' placed below the reference line with '(4)' written in the tail. What does this specify?

Accepted Answer

Perform four separate Magnetic Particle tests on the arrow side of the joint.

Answer

Placing the 'MT' symbol below the reference line indicates the test is for the 'arrow side.' Information in the tail of the symbol provides supplementary data. In this context, the number in parentheses specifies the number of examinations required.

CWI Practice Test

CWI Practice Test

CWI NDE Methods and Symbols Questions and Answers