Weld Symbols 53713q

What are the basic welding symbols?

Welding symbols used in Australia are based on the Australian Standard AS 1100.101-1992. You can research the full range of welding symbols in the Engineering Drawing Handbook produced by Standards Australia and the Institution of Engineers. Here is a selection of basic symbols to learn as a first step. (Click on image to open larger drawing in new window.)

Weld finishes (contour) With butt welds the welding symbol will tell you the final finish or contour, • • •

It may be ground off flush. It may be left in its original state – convex. Concave welds are rarely used.

Examples

Welding symbols allow the engineer or draftsperson to communicate detailed information about the weld to the welder. Examine the examples below which show the weld required and the symbol that conveys this information.

Compare these two symbols. Note what is different and what each one means.

10mm fillet weld other side of arrow 6mm fillet weld arrow side Weld on site Use the gas metal arc welding process

6mm fillet weld on both sides Weld all round Weld on site Use the gas metal arc welding process

What are the components of welding symbols? Basic welding symbols communicate information about the type, size and position of welds in welded ts. They are drawn to Australian Standard AS 1100.101-1992 A welding symbol can be made up of any of these eight elements: • •

•

a reference line, which is always drawn parallel to the bottom edge of the drawing or to the base line of the view where it is used. an arrow, which indicates the location of the welded t. The side nearer the arrow is known as the arrow side and the further side is called the other side. The arrow connects to the reference line and welding symbol. welding symbols

• • • • •

supplementary symbols, eg R30 means that the hole has a radius of 30mm the dimension of the weld finish symbol, eg C = chipping, G = grinding, M = machining, R = rolling, P = peening a tail specifications and process – references to these are placed in the tail.

http://metal.brightcookie.com/2_draw/draw_t7/htm/draw7_2_2.htm

Why do we use welding symbols? Welding symbols are used to reduce the number of words on an engineering drawing and so save space and time. Once you become accustomed to the symbols you will see that they help you to understand exactly what needs to be done. Welding symbols are drawn to Australian Standard AS 1101 Part 3. They are universal so regardless of where you go in the world the symbols remain the same. Welding symbols can also give more information than would be possible with words. Symbols can define: • • • •

t configuration eg bevelled, butt weld or double bevel type of weld eg fillet, lap, edge, corner, slot, or plug type of welding process eg gas metal arc welding, and whether to weld on site or in the workshop.

Examples Meaning

Symbol

The t is to be welded on both sides with a 6mm fillet weld. Weld on site

Weld all round The near or arrow side is to be welded with a single V butt weld while the other side is to be welded with a 6mm fillet weld. This is to be done on site.

Welding symbols help to convey information clearly. Look at the figure below. You could use the words on the right to describe the welding needed but there may be no room for the drawing itself. Alternatively, you could use the welding symbols on the left. What would you choose?

Weld the other side - 10mm leg length and 50mm long. The centre of the weld to the centre of the next weld is to be 200mm long. On the same side as the arrow, weld a 6mm leg length and 100mm long. The centre of the weld to the next weld centre is to be 500mm long.