Welding Symbols Guide and Chart Fillet Weld and Groove Weld. In order to communicate with others, living beings invented a language. A language can help individuals to achieve what they want, and for the larger community to achieve wonder. Thanks to human language, we humans can reach the pinnacle of development that currently no other creature can contest.
Even among ourselves (humans) the development may vary and it depends on so many factors including the language being used inside the society. The developed community often has a complex structure of language (e.g. English, Germans, and Arabic). That support the member of the community to interact with each other while avoiding misunderstanding.
The complexity of language is also found in a particular activity. For example when the same word is used differently when we’re engaging in different activities. The use of language for a specific purpose is proven to be more effective and efficient rather than using the language generally.
In a work field like engineering, there are so many terms that will make scholars scratch their heads in confusion, not necessarily because they’re dumb, but because they’re not accustomed to the way the language is applied. To further add, the engineering field also incorporates drawings and symbols in addition to the words themselves. Giving you enough insight as to why communicating efficiently and effectively is so important.
Table of Contents :
AWS Weld Symbols Chart :
SPECIFIC LANGUAGE IN WELDING.
Now in welding, there is a set of language that you need to accustom yourself to, it is the welding symbols. A welding symbol is an effective way to communicate the weld necessity among workers. A symbol that contains a few lines, some weird shapes, and enough words, but so much information. While there may be slight varieties in a different regions, the syntax usually looks like this:
Looks pretty crazy right? Imagine if that much information is written in words, it could take pages, therefore taking hours to write and more hours to interpret, thus making the job less time-efficient and in the end prolonging the manufacturing process.
WELDING SYMBOLS ELEMENTS
Now we know that the welding information is compressed so much in the welding symbols. We need to learn the different aspects of every single element to avoid misinterpretation. Basically, there are 3 parts of the welding symbol:
The arrow is the part that specifies the location of welding at one end and is connected to the reference line in the other. The arrow segment contains the following:
- THE HEAD ARROW.
This element is used to pinpoint the exact location of the joint. Sometimes the line is not straight but bent to point to the specific member of the joint that should be beveled.
- CIRCLE INJUNCTION.
The circle that centered where the arrow and the reference line intersected is being used to indicate that the weldment is circling the joint. Commonly found in fillet weld, where you need to fully weld the joint even to the smallest part of the joint, so basically it’s like welding a pipe that is fully round weld is necessary. It may or may not be there depending on the design of the joint.
- THE FLAG.
No, it’s not there to indicate which nationality the designer is. Just like how it’s described in figure 1, it tells you whether the welding should be done in the workshop (with the absence of the flag) or in the field during assembly or erection (with the flag being there). Such information is important because it deals with the process sequence that you clearly don’t want to disrupt.
The Reference Line.
The reference line contains more information regarding the detail of the welding like the joint design, weld size, weld pattern, and many others. The upper and lower part of the reference line has the same elements for each side, the difference is the side on which the welding should be done.
The lower part is the narrow side, which means the side pointed by the arrow should be welded like what the elements there told you. Similar to the upper part, only the difference is the elements are explaining the other side of the joint.
This is particularly useful when the two sides have different detail of the joint, and this also helps to avoid using too many welding symbols in one joint. Another important thing is no matter where is the arrow or the tail, the position of the elements should be the same as portrayed in figure 1. The reference line segment contains the following:
GROOVE DESIGN (BRACKET).
As we know, there is just so much groove design in welding. Fillet weld, V-groove, X-groove, U-groove, and I-groove is just a few of many. Different groove designs should have a distinct symbol to minimize the chance of making a mistake. In addition, some symbol also represents a different type of welding process, in figure 3, displays the most commonly used welding symbols.
THE WELD SIZE (S and E).
The dimension of welding is important because it’s directly related to the ability of the joint to handle the given load. That’s why this element serves to display the weld size required by the design. The S (Size) is mostly used in fillet weld, where it represents the leg size of the weld.
While the E (Effective throat) is mostly used in groove welding, where it represents the depth of the groove itself. Other than that, it’s pretty self-explanatory in figure 1.
THE WELD PATTERN (L and P).
Although not really common, some project does not need to be fully welded to allow some deformation and avoid crack. Most of the application of this letter is on fillet welding, where L (Length) specifies the length of the fillet weld and P (Pitch) specifies the length between two centers of the single weld length. To be more specific, see the example provided in figure 4.
ROOT OPENING (R).
Root opening is the little gap between two separate base metals to make root pass (the first pass in welding butt joint where you purposely allow some burn through to fill the other side of the weld joint) possible. Although it’s so hard to manipulate the size to be precise during the fitting process, this symbol is still applicable on the smaller welding scale.
ANGLE OF BEVEL (A).
The shape of the bevel would form an angle that can be manipulated for better joint quality. Because the angle is too small, it will not allow the welder to have good penetration during welding which will result in incomplete penetration defects and reduce the joint strength.
Even so, the wider angle doesn’t necessarily mean it’s good, the larger area being chipped off the base metal means that it requires an extra effort to weld, and although the quality of the joint is great, the extra work time doesn’t really worth it. The optimum angle would be around 50 – 70 degrees.
CONTOUR (line above angle).
The contour of the welding or the surface shape of the weld bead sometimes needs to be manipulated according to the standard application of the welding itself. The common option is to leave the surface convex, concave, or flushed.
To manipulate the surface shape is not only the welder’s responsibility, while it surely helps, but the finishing contour is also usually shaped by grinding, chipping, or any other process done by another worker.
This part is related to the contour section. Where this symbol is designed to specify which process is used to achieve the desired contour. The common process for finishing the weld surface is grinding (G), chipping (C), and machining (C).
The Tail Welding Symbol.
Even when the arrow and reference line seems to cover all the required information regarding the welded joint. It’s still possible to insert more information such as the welding process, the examination process, the reference document (Welding Procedure Specification), etc.
Such information is placed on the end of the welding symbol, the tail. The tail is not always there, it depends on the need to insert additional information or not, so it can be omitted when such information is not required for the joint. Check figure 5 for the example.
The information in this article can only answer the question about the welding symbol in general. Because there are other variables that are not mentioned above, a variation like bent arrow line and some other.
The other common variation is the welding symbol for staggering and intermittent weld and double reference lines in a single welding symbol. But for now, it’s better for you to digest this much information first before you lookup for another.
If you don’t mind a few tips, understanding the welding symbol is just like mastering any other language. Where you need to practice a lot so you can understand and know its proper use. So, the next step would be practicing deciphering any welding symbols you can find and go back to find references when you’re stuck.