Enter the sprue area, runner area, and total gate area into the calculator to determine the gating ratio.

## Gating Ratio Formula

The following equation is used to calculate the Gating Ratio.

GR = 1 : AR/AS : AG/AS

• Where GR is the 3-term grating ratio
• AS is the sprue area
• Ar is the runner area
• Ag is the gate area

## What is a Gating Ratio?

Definition:

A gating ratio is a term used to describe the relative cross-sectional areas of components of a gating system.

## How to Calculate Gating Ratio?

Example Problem:

The following example outlines the steps and information needed to calculate the Gating Ratio.

First, determine the area of the spue. In this case, this is 10ft^2.

Next, determine the area of the runner. In this example, this is 20ft^2.

Next, determine the area of the gate. This is 40ft^2.

Finally, calculate the gating ratio using the formula above:

GR = 1 : AR/AS : AG/AS

GR = 1 : 20/10 : 40/10

GR = 1 : 2 : 4