How to determine Determine Weld Size and Length

The determination of weld size and length for a flange-plate splice joint in a welded connection can be done using applicable design codes and standards. The specific formula may vary depending on the code being used, but I can provide a general overview of the process.

1. Refer to the applicable design code: Different design codes, such as the American Welding Society (AWS) D1.1 Structural Welding Code or Eurocode, provide guidelines and formulas for determining weld size and length based on the joint configuration, material properties, and applied loads.
2. Calculate the required throat thickness: The throat thickness is a key parameter used in determining the weld size. It represents the effective size of the weld, considering both the leg size and the fusion between the base metal and the weld metal. The required throat thickness can be calculated based on the design forces and the permissible stress or strength reduction factors specified in the design code.
3. Determine the leg size: The leg size refers to the length of the weld on each side of the joint. It is typically specified as a fraction of the throat thickness, such as 0.7 times the throat thickness. The specific leg size may vary depending on the joint type, design requirements, and code provisions.
4. Calculate the weld length: The weld length is determined based on the required strength and the load distribution along the joint. It is generally designed to ensure sufficient strength and to prevent stress concentration or premature failure. The weld length can be calculated by dividing the applied load by the permissible stress or strength of the weld material, considering the appropriate safety factors and reduction factors specified in the design code.
5. Consider additional factors: In addition to the formulas provided in the design code, other factors such as joint configuration, weld accessibility, and welding process may influence the determination of weld size and length. These factors should be taken into account to ensure practicality and feasibility during fabrication.

It is important to note that the specific formulas and procedures for determining weld size and length may differ depending on the design code being used and the specific joint configuration. It is recommended to consult the relevant design code or consult with a qualified welding engineer or structural engineer to ensure accurate and compliant weld design