Throat Thickness for Fillet Weld Calculator

Throat Thickness Formula:

\[ t_{throat} = 0.707 \times t_{plate} \]

Throat Thickness (mm):

Minimum Throat (mm):

Maximum Throat (mm):

1. What is Throat Thickness for Fillet Weld?

Definition: The throat thickness is the shortest distance from the root to the face of the weld.

Purpose: It's a critical measurement in weld design that determines the strength of a fillet weld.

2. How Does the Calculator Work?

The calculator uses the formula:

\[ t_{throat} = 0.707 \times t_{plate} \]

Where:

\( t_{throat} \) — Throat thickness (mm)
\( t_{plate} \) — Thickness of the plate being welded (mm)
0.707 — Constant for equal leg fillet welds (cosine of 45°)

Explanation: For a 45° fillet weld with equal legs, the throat thickness is approximately 70.7% of the plate thickness.

3. Importance of Throat Thickness Calculation

Details: Proper throat thickness ensures weld strength meets design requirements and accounts for manufacturing tolerances.

4. Using the Calculator

Tips: Enter the plate thickness in mm and tolerance percentage (default ±5%). The calculator provides nominal, minimum, and maximum throat thickness values.

5. Frequently Asked Questions (FAQ)

Q1: Why is throat thickness important?
A: It directly affects the strength of the weld. The throat area resists shear forces in the joint.

Q2: What's the typical tolerance for fillet welds?
A: ±5% is common, but this may vary based on welding standards and application requirements.

Q3: Does this apply to unequal leg fillet welds?
A: No, this formula is specifically for equal leg fillet welds. Unequal legs require different calculations.

Q4: How does weld size relate to throat thickness?
A: For equal leg fillet welds, the leg size is typically 1.4 times the throat thickness.

Q5: What standards govern throat thickness?
A: Common standards include AWS D1.1 (USA), ISO 2553 (international), and EN 1993-1-8 (Europe).