AWS A2.4:2020 pdf free download

AWS A2.4:2020 pdf free download.Standard Symbols for Welding , Brazing , and Nondestructive Examination.
NOTE: Numbered .subclauses in this annex relate to similarly numbered suhckiuses in the text of AWS A2.4. e.g.. D6. 9 is a commontary on 6.9 in the text.
D4.5 Welding Symbols. Figure 4.3 provides the generic appearance of a welding symbol. The letters S. D, A, R. L, P. and N within the figure are used as placeholders for specific numerical values used within the symbol to specify sizes for the features of the weld or welds indicated by the symbol. Letters such as these would not normally appear on finished drawings.
In addition to letters reflecting numerical values, the letter F is used as a placeholder for the letters corresponding to finishing designators as provided in 6.1 3.2 and 6.13.3, and the letter T refers to detailed process or specification references that may he shown in the tail of the welding symbol as provided in 6.12.
While 4.5 states the minimum required elements in a welding symbol are a reference line and arrow, it is good practice to include a weld symbol or other details to adequately communicate design intent: however, it is not a requirement. A welding symbol with only a reference line and an arrow and no other requirements will delegate welding details to the discretion of the fabricator. The end result may not meet the design intent.
D6.9 Field Veld Symbol. Welds arc designated to be made in the field by the addition of the field weld symbol when the welding symbols are added to a drawing. It should be understood, however, that the placing of field weld symbols on drawings at the design stage does not preclude further discussion by the parties involved nor different decisions regarding where the welding will he done. If changes are made, the drawings should he revised and the field weld symbols should he added or deleted, as appropriate.
D6.1O.2 Changes in the Direction of Welding. Abrupt changes in direction of welding are often accompanied by changes in the nature and direction ot loading. As part of weidment design. the identification of an abrupt change in the direction of welding for a given application is beyond the scope of this standard. It may require changes to welding type or procedure(s) to produce welds that will perform safely and effectively in service. Welding techniques such as boxing or hold-hacks may be necessary to satisfy design requirements. For these reasons, where an abrupt change in the direction of welding exists, it shall he addressed by using separate welding symbols to either side of the change, multiple arrow lines, or the all-around symbol. This determination should be made by the appropriate technical authority responsible for weidment design.AWS A2.4:2020 pdf free download.