KEVOS® MAKEOS · Fabrication
Casting Solidification Time and Riser Check
Will this cylindrical riser solidify after the casting, and what pattern size allows for shrinkage?
Casting and riser moduli and solidification times by Chvorinov’s rule, the riser-to-casting modulus ratio, and pattern size from a shrinkage allowance.
Open the calculatorRuns in your browser. No account needed.
How this tool works
Inputs, units and where to find them
| Input | Unit | Typical source |
|---|---|---|
| Casting (section) volume | cm³ | Volume of the casting or the section the riser must feed, from CAD. |
| Casting cooling surface area | cm² | Surface area of that section that cools into the mould (exclude faces joined to other sections). |
| Riser diameter | mm | Riser diameter. |
| Riser height | mm | Riser height. |
| Mould constant B | min/cm² | Mould constant for the metal and mould, from foundry trials or data. |
| Required riser/casting modulus ratio | Riser modulus must exceed the casting modulus by this factor (1.2 is a common foundry rule). | |
| Part dimension for pattern | mm | Finished part dimension to convert to a pattern size. |
| Shrinkage allowance | % | Patternmaker’s shrinkage allowance for the alloy and mould (e.g. about 1% for grey iron, 2% for steel). |
Method and formulas
- Modulus M = V ÷ A (cm). Riser (top and side cooling): V = πD²H/4, A = πDH + πD²/4.
- Chvorinov: t = B × M².
- Pattern dimension = part dimension × (1 + shrinkage).
- Example: the casting modulus is 2.2222 cm and the riser’s 2.7013 cm, a ratio of 1.2156.
Limitations
- Chvorinov’s rule is an approximation; riser feeding distance and volume (shrinkage demand) must also be checked.
- Exothermic or insulated sleeves change the riser modulus.
- Example values are illustrations. Replace them with values for your actual task.
Typical uses
- Check that a riser feeds a casting section
- Compare riser sizes
- Size a pattern for shrinkage
Who it is for
- Foundry engineers
- Pattern makers
- Casting buyers
What you get
- Casting and riser moduli
- Solidification times
- Modulus ratio
- Pattern dimension
Interpreting the result
- Feeding needs both a larger modulus and enough liquid volume in the riser.
References
- Machinery’s Handbook, 29th edition (Industrial Press, 2012), printed pp. 1405–1420. Topic reference; no source tables or recommended settings are reproduced.
WORKOS tools are screening and decision-support utilities. Verify important financial, engineering, safety, legal or operational decisions using appropriate professional standards and your organisation’s approved data.
Open the Casting Solidification Time and Riser Check calculator
