Injection Molding worked example
Barrel Residence Time with barrel melt capacity of 130 g: a worked example
This worked example runs the barrel residence time numbers for a tougher week than the baseline: barrel melt capacity of 130 g instead of the typical 250 g. Calculate resin residence time in the barrel to check for thermal degradation risk, especially for heat-sensitive materials.
The inputs for this scenario
- Barrel melt capacity: 130 g (the input this scenario stresses; the baseline uses 250)
- Actual shot weight per cycle: 55 g (held at the documented default)
Working through the calculation
- The calculation starts from the formula this tool documents: Barrel shots = Barrel capacity / Shot weight.
- Ratio works out to 2.36 min at these inputs, and this is the headline figure for the scenario.
- Raw ratio works out to 2.36 value at these inputs.
- Conversion factor works out to 1 x at these inputs.
- Denominator works out to 55 value at these inputs.
How this compares with the baseline
- Against the tool's baseline example, where barrel melt capacity sits at 250 g and the headline result is 4.55 min, this scenario comes in 48% below the baseline at 2.36 min.
- Use it when selecting a machine for a part, qualifying a heat-sensitive resin, or diagnosing degradation defects like black specks, yellowing, or splay. A result at this level usually justifies acting on the stressed input before touching anything else, because every other figure in the table is downstream of it.
Results at a glance
- Ratio: 2.36 min (headline result)
- Raw ratio: 2.36 value
- Conversion factor: 1 x
- Denominator: 55 value
Run it with your numbers
- To rerun this with your own numbers, open the live Barrel Residence Time calculator, set barrel melt capacity to your actual value, and adjust the remaining inputs to match your operation.
Last reviewed 2026-05-12.