456A Blueprint Reading, Weld Symbols & Joint Preparation

Question 1

On a weld symbol, on which side of the reference line is a weld symbol placed to indicate the 'arrow side' of the joint?

Accepted Answer

Below the reference line

Answer

According to AWS A2.4 (and the equivalent CSA standard used in Canada), weld symbols placed below the reference line indicate welding on the arrow side of the joint (the side the arrow points to). Symbols placed above the line indicate the other side. This convention is consistent throughout all standard weld symbols.

Question 2

What does a weld symbol with a circle at the junction of the arrow and reference line indicate?

Accepted Answer

Weld all around the joint

Answer

A small circle at the junction of the arrow and reference line is the 'weld all around' symbol. It indicates that the weld is to be made completely around the joint perimeter. It is commonly used for tube-to-plate connections, pipe attachments, and structural sections where a continuous seal weld is required.

Question 3

What does a filled (solid) flag at the junction of the reference line and arrow indicate on a weld symbol?

Accepted Answer

Field weld — the weld is to be made at the installation site, not in the fabrication shop

Answer

A solid (filled) flag at the arrow-reference line junction is the field weld symbol. It indicates that the weld is not to be made in the fabrication shop but at the job site during erection or installation. This is important for shipping logistics, inspection scheduling, and welding procedure applicability.

Question 4

On a fillet weld symbol, where is the weld size (leg length) shown?

Accepted Answer

To the left of the weld symbol

Answer

The weld size (leg length in mm) for a fillet weld is written to the left of the fillet weld symbol. The length of the weld (if specified) is written to the right of the symbol. Both values appear on the same side of the reference line as the symbol (arrow side below, other side above).

Question 5

What is the meaning of the number in parentheses on a groove weld symbol, such as a V-groove with (5) written in it?

Accepted Answer

The root opening (gap between the parts) in millimetres

Answer

A number in parentheses within a groove weld symbol represents the root opening (the gap at the root of the joint) in millimetres. This is a critical dimension for welding procedure setup, affecting root pass penetration. It is distinct from the groove angle (shown outside the symbol) and the weld depth.

Red Seal Welder 456A Practice Test

Red Seal Welder 456A Practice Test

456A Blueprint Reading, Weld Symbols & Joint Preparation