Case Study: Simulation-Driven Rescue of a Cast-Iron Water Pump Body
From chronic cold-shuts to <1% defects at scale—how a classic CI pump body hit 82% yield and shipped >10,000 units on time.
- Yield ~82%
- Defects <1% over 10,000+ units
- Order recovered on schedule
The Problem
No 3D model—only legacy drawings and a troubled “current part”
Cold-shuts and misruns in green sand
Drafts/tapers wrong → dimensional drift, drying distortion
Behind on a 10k+ unit order; heavy scrap.
Our Approach
Rebuilt the 3D model (from drawings + measured part; fixed drafts/tapers).
Ran casting simulations to eliminate cold-shut vectors.
Printed an ABS master for dimensional sign-off.
Finalized gating/feeding and core design; built pattern/coreboxes.
Shop-floor launch with alloy guidance, pour window, and molding notes.
Key design choices
- Balanced runners; smooth front-fill (reduce bifilm)
- Risers repositioned for directional solidification
- Cleaned internal transitions (less turbulence/oxide entrapment)
- Draft/taper corrections for consistent green-sand release
Results
Scrap: frequent cold-shuts
Yield: ~65–70% (est.)
Delivery: behind
Dimensions: variable
After
Defects: <1% (client-reported)
Yield: ~82%
Delivery: recovered
Dimensions: passed ABS + in-process checks
Implementation Notes
- Process: green sand, cast iron (per customer spec)
- Pour window & chemistry guidance provided
- Tooling: pattern + coreboxes (delivered)
- Launch support: first-pour assistance + molding notes
Struggling with cold-shuts or yield?
We design the gating, prove it in simulation, and stand beside your first pours.
Typical response within 1 business day.