AWS C3.8M-C3.8 pdf free download
AWS C3.8M-C3.8 pdf free download.Ultrasonic Examination of Brazed Joints.
4.2.3 Tank. The tank used for immersion testing shall be of sufficient size to permit the submersion of the brazed assembly or the entire braze joint area of the assembly and the search unit such that the required inspection can be performed.
4.2.4 Turntable. A turntable niay be used to rotate circular assemblies during nondestructive examination. It shall he suitable for the intended purpose.
4.2.5 Bridge. The bridge shall be mounted over the tank and shall move smoothly over the working area of the tank. The bridge shall be capable of being accurately indexed manually or automatically, or both, as required to examine the brazed joint area.
4.2.6 Carriage. The carriage shall be mounted on the bridge and shall support the manipulator. It shall have uniform, smooth operation over its working distance and shall be capable of traversing manually or automatically, or both, as required to examine the brazed joint area.
4.2.7 Manipulator. The manipulator shall be rigidly attached to the carriage and support the search unit. It may provide fine angular adjustment in two planes at right angles to each other.
4.2.8 Recorder. A device capable of producing a C- scan facsimile of the brazed joint is required for the immersion testing of all brazed joints unless otherwise specified on the approved nondestructive examination procedure.
4.2.9 Alarm. When a facsimile recorder is not used, an audible electronic defect alarm or stop-on-defect alarm shall be used.
4.2.10 Couplants. Couplants shall permit the efficient transmission of ultrasonic energy between the transducer and the surface of the brazement being inspected. For water immersion testing, rust inhibitors and wetting agents may be added. Neither the couplant nor the additives shall be detrimental to the brazed products being inspected.
4.3 Required Procedures
4.3.1 Operator Qualification. Ultrasonic examination operators shall he qualified as specified by NAS 410, Level II or III.
4.3.2 Reference Standards. Following the procedures set by ASTM E 114 and ASTM E 214, a representative brazed sample (same material and/or materials combinations along with representative geometries) shall he made with sizes of discontinuities induced in the braze interface that would represent the detectability limits required by the Organization Having Quality Responsibility. The ultrasonic methods shall be developed and specified by the operator, certifying that the disconlinuities in the Reference Standard can be found and/or imaged properly.
4.4 Brazemcnt Qualification for Ultrasonic Exam in at ion
4.4.1 Preparation of Brazements for Examination. The surface of the brazement to be examined shall have no brazing filler material, flux residue, or stop off that would prevent the proper examination of the joint. The finish of this surface shall be 2.8 micrometers (pm) 1110 micro- inches (pin.)1 average roughness (Ra) maximum.
4.4.2 Brazement Configuration. All brazernents requiring ultrasonic examination shall he of a configuration suitable for testing. The outer surface through which the sonic energy enters must he accessible to the transducer. The surface shall have flO steps. lands, slots, or holes located so as to prevent the proper examination of the joint, as determined by the Organization Having Quality Responsibility.
4.4.3 I)ocumentation. A written ultrasonic procedure specifying the equipment to be used and the techniques to he used to calibrate the equipment and examine the assemblies shall be required. This procedure shall also specify how the assemblies shall be identified and how the test results shall he documented. This procedure shall be approved in writing by the Organization Having Quality Responsibility for the product.AWS C3.8M-C3.8 pdf download.
