Transverse fillet weld
A transverse fillet weld is a type of weld that is used to join two pieces of metal at a right angle, forming a T-joint. This type of weld is commonly used in structural applications, such as in the construction of buildings, bridges, and other steel structures.

Size of the weld
The size of a fillet weld refers to the perpendicular distance between the root of the weld and the face of the weld. It is typically expressed in terms of the throat thickness, which is the minimum distance from the root of the weld to the face of the weld.

Relation between the size of the weld and throat thickness
The size of a transverse fillet weld is equal to the square root of 2 times the throat thickness. In other words, the size of the weld is approximately 1.414 times the throat thickness.

Explanation
The throat thickness of a weld is a critical parameter that determines the strength and integrity of the joint. It is the effective area of the weld that resists the applied loads and provides the necessary bond between the two pieces of metal.

The size of the weld is directly related to the throat thickness, as it represents the overall dimensions of the weld. In a transverse fillet weld, which is a triangular-shaped weld, the size is measured along the legs of the triangle.

The relationship between the size of the weld and throat thickness can be derived from geometry. By using the Pythagorean theorem, which states that in a right triangle, the square of the hypotenuse is equal to the sum of the squares of the other two sides, we can determine the size of the weld.

In a transverse fillet weld, the throat thickness represents one of the legs of the triangle, and the size of the weld represents the hypotenuse. By substituting the values into the Pythagorean theorem equation, we get:

(Size of the weld)^2 = (throat thickness)^2 + (throat thickness)^2
(Size of the weld)^2 = 2(throat thickness)^2
Size of the weld = √2(throat thickness)

Therefore, the size of a transverse fillet weld is equal to the square root of 2 times the throat thickness. This relationship is important in determining the dimensions of the weld and ensuring its adequacy for the intended application.

Conclusion
In a transverse fillet weld, the size of the weld is equal to the square root of 2 times the throat thickness. This relationship is derived from geometry and is important in determining the dimensions of the weld for structural applications.