Area at Top Section of Sprue Calculator

Area at Top Section Formula:

\[ A_t = A \times \sqrt{\frac{h_c}{h_t}} \]

Area at Top Section (m²):

1. What is Area at Top Section of Sprue?

Definition: This calculator determines the required area at the top section of a sprue based on the choke area and metal heads.

Purpose: It helps foundry engineers design proper gating systems for casting processes.

2. How Does the Calculator Work?

The calculator uses the formula:

\[ A_t = A \times \sqrt{\frac{h_c}{h_t}} \]

Where:

\( A_t \) — Area at top section (m²)
\( A \) — Area at choke section (m²)
\( h_c \) — Metal head at choke section (m)
\( h_t \) — Metal head at top section (m)

Explanation: The area at the top is calculated based on the ratio of metal heads to ensure proper flow control.

3. Importance of Sprue Design

Details: Proper sprue design ensures smooth metal flow, minimizes turbulence, and prevents air aspiration in the casting process.

4. Using the Calculator

Tips: Enter the choke area, metal head at choke, and metal head at top. All values must be > 0. Results include ±5% tolerance.

5. Frequently Asked Questions (FAQ)

Q1: Why is the top area larger than the choke area?
A: The area increases to compensate for decreasing metal velocity as it falls, maintaining proper flow rate.

Q2: What does the ±5% tolerance represent?
A: It accounts for variations in metal viscosity, surface tension, and flow characteristics.

Q3: How does metal head affect the calculation?
A: Higher metal head at choke relative to top increases the required top area.

Q4: What if my sprue isn't vertical?
A: This calculator assumes vertical sprues. Angled sprues require additional considerations.

Q5: How precise should my measurements be?
A: Measure metal heads to within ±1cm and areas to within ±1cm² for best results.