Comparison between Sow Molds and Ingot Molds, covering shape, materials, functions, applications, replacement frequency, and other key differences:
| 1. Shape & Structural Design | ||
| Aspect | Sow Molds | Ingot Molds |
| Typical Shape | – Thick, block-like (trapezoidal or rectangular, 500–2,000 kg) | – Slender, standardized bars (“T” or trapezoidal, 20–25 kg) |
| – Rough surface, minimal internal features | – Smooth surface, precise dimensions | |
| Dimensions | – Example: 1.5m × 0.6m × 0.5m (for 1,000 kg ingots) | – Example: 0.8m × 0.15m × 0.1m (for 25 kg ingots) |
| Internal Design | – Reinforced for bulk strength (fewer ribs) | – Multiple ribs (to prevent warping) |
| – Simple interior surface | – Mold release slopes or grooves | |
| 2. Manufacturing Materials | ||
| Aspect | Sow Molds | Ingot Molds |
| Primary Materials | – Gray cast iron (HT250): Low cost, heat-resistant | – Gray cast iron (HT200): Lightweight |
| – Ductile iron (QT500-7): Superior thermal shock resistance | – Low-carbon steel (Q235B): For rapid cooling | |
| – High-chromium cast iron (Cr 15–20%) | – Nickel-plated variants (anti-stick) | |
| Material Properties | – High thermal conductivity | – Moderate thermal conductivity |
| – Carbon content: 3.0–3.5% (gray iron) | – Carbon content: 2.5–3.2% (gray iron) | |
| 3. Function & Applications | ||
| Aspect | Sow Molds | Ingot Molds |
| Primary Function | – Cast large aluminum blocks (“sows”) for remelting or rolling | – Produce standardized ingots for direct sale or machining |
| – Focus on slow cooling to preserve metal quality | – Prioritize rapid solidification and surface finish | |
| Applications | – Primary smelters (electrolytic aluminum) | – Downstream processing plants (e.g., extrusion, forging) |
| – Recycling plants (bulk scrap remelting) | – Commercial trade (standardized units) | |
| Cooling Method | – Natural cooling (4–8 hours) | – Forced cooling (water/air jets, 10–30 minutes) |
| – Insulation layers (e.g., ceramic blankets) | ||
| 4. Replacement Frequency & Maintenance | ||
| Aspect | Sow Molds | Ingot Molds |
| Service Life | – 300–500 pours (prone to thermal cracking) | – 1,000–1,500 pours (lightweight design) |
| – Repairable via welding | – Less frequent repairs | |
| Failure Modes | – Thermal fatigue cracks (interior surface) | – Surface oxidation peeling |
| – Warping (difficulty demolding) | – Dimensional inaccuracy due to wear | |
| Maintenance | – Inspect for cracks every 50 uses | – Clean slag every 100 uses |
| – Apply anti-stick coatings (e.g., graphite) | – Calibrate dimensions periodically | |
| 5. Industry Use Cases | ||
| 1) Sow Molds Example: | ||
| An electrolytic aluminum plant uses HT250 gray iron sow molds to cast 1,200 kg blocks for rolling mills. Molds are replaced every 6 months. | ||
| 2) Ingot Molds Example: | ||
| An extrusion factory employs Q235B steel ingot molds to produce 22.5 kg T-shaped ingots at 200 units/hour, with a mold lifespan of 2 years. | ||
| 6. Key Differences & Selection Guidelines | ||
| Factor | Sow Molds | Ingot Molds |
| Design Focus | Bulk casting, slow cooling, durability | Standardization, speed, surface quality |
| Ideal Scenario | Primary smelting or remelting | Downstream processing or trade |
| Cost Efficiency | Higher initial cost, saves remelting energy (~15%) | Lower cost, mass production efficiency (~30% faster packaging) |
| Recommendations: | ||
| 1) Use Sow Molds for intermediate products requiring remelting or rolling. | ||
| 2) Choose Ingot Molds for final products needing standardized shapes and fast turnover. | ||
This comparison highlights how material choices, design priorities, and operational needs drive the selection between these critical aluminum casting tools. For more professional guidance, please contact our aluminium casting engineer.
