AWS B1.10M-B1.10:2016 pdf download.Guide for the Nondestructive Examination of Welds
1.2 Advantages and Limitations of the Examination Method. The advantages and limitations of the examination method help to determine which method(s) is (are) best for detecting discontinuities of a particular size, shape, and orientation. For example, radiography can detect discontinuities with major planes aligned parallel with the radiation beam, such as cracks oriented normal to material surfaces. Radiography, however, usually cannot detect laminations in material or cracks oriented parallel to the plate surface. Conversely, ultrasonic examination can detect cracks oriented in any direction provided the sound beam is oriented essentially perpendicular to the major axis of the crack.
1.3 Acceptance Standards. The statement“the weld shall be radiographically examined" is incomplete unless acceptance standards are specified. Acceptance standards define characteristics of discontinuities. They also establish upper and lower limits that determine the acceptance or rejection of a given discontinuity in conformance with the applicable acceptance standard. Discontinuities may be acceptable providing their size and distribution are within specified limits. Some aceptance standards are shown in Annex C.
1.4 Cost. Costs of the various examination methods depend on the particular situation. Two factors that should be considered in selection of a nondestructive examination method are the cost of performing the examination and of the equipment.
Visual examination is usually the least expensive, but it is limited to the detection of surface discontinuities. In general, the cost of radiography, ultrasonic, or eddy current examination is higher than the cost of visual, magnetic particle, or liquid penetrant examination. To determine the method(s) that will best satisfy the intended purpose and minimize cost, qualfied personnel should be consulted.
1.5 Procedures. It should be recognized that all NDE methods must be performed in accordance with an approved procedure which is available to the technician performing the test or examination. This is almost always a requirement of the applicable code. Only by following a documented (written) procedure can the NDE technician ensure adherence to codes and specifications applicable to the fabrication under test. These procedures should be documented to provide all details of test preparation, performance, and interpretation to ensure reliability and reproducibility of results.
3. Terms and Definitions
The terminology used in this guide is that established in AWS A3.0M/A3.0, Standard Welding Terms and Definitions Including Terms for Adhesive Bonding, Brazing, Soldering, Thermal Cutting and Thermal Spraying. Nondestructive examination (NDE) is a general term used in this text to identify the common examination methods used for evaluation of welds and related materials without destroying their usefulness.AWS B1.10M-B1.10 pdf download.