LPDC and gravity casting molds differ greatly in working pressure, exhaust structure and cooling layout, determining their applicable aluminum casting scenarios and product quality.
LPDC casting mold works under stable pressure of 0.02–0.05MPa, while gravity casting mold relies on natural liquid flow with zero auxiliary pressure, leading to different gating system designs.
Gravity casting mold adopts open exhaust structure with 20% larger exhaust area than LPDC molds, adapting to fast liquid filling and high gas volatilization volume.
The cooling channel spacing of gravity casting molds is fixed at 15–22mm, 10% wider than LPDC molds, matching its slower solidification speed of thick-walled castings.
LPDC casting mold porosity shrinkage rate is controlled below 0.8% via CAE simulation, while gravity casting allows a standard defect rate within 1.2% under normal processes.
Aluminum wheel mold for gravity casting is suitable for thick-wall products above 5mm, while LPDC aluminum wheel mold stably produces 3–5mm thin-wall wheel blanks.
H13 hot-work steel serves both mold types, yet gravity molds have 15% longer single-cycle service life due to lower repeated pressure impact.
EV structural part mold using gravity casting focuses on strength structure, while LPDC EV molds prioritize lightweight thin-wall forming accuracy.
CPC counter-pressure casting mold integrates the advantages of the two, with working pressure 3 times higher than conventional LPDC casting molds for ultra-low defect production.
Casting mold trial-test standards vary by type; gravity molds need 4 trial batches, 1 time more than LPDC molds to verify stable filling balance.
Procast CAE simulation parameters are adjusted differently: gravity molds focus on flow velocity balance, while LPDC molds emphasize pressure holding solidification consistency.
The structural differences between LPDC casting mold and gravity casting mold are core knowledge for aluminum alloy foundry process selection. In industrial mass production, mold structural design directly affects casting yield, production efficiency and mold maintenance cycle. Gravity casting mold features simple structure and low manufacturing cost, suitable for large-batch thick-walled aluminum casting products with low surface precision requirements. LPDC casting mold requires high-precision sealing and pressure-resistant structure, which is more applicable for high-precision aluminum wheel mold and lightweight EV structural part mold. Although both types of molds adopt H13 hot-work steel as the mainstream raw material, their processing tolerance, channel layout and exhaust design cannot be interchanged blindly. CPC counter-pressure casting mold, as an upgraded process mold, combines the pressure control advantage of LPDC and the high-efficiency filling of gravity casting, further reducing casting mold porosity shrinkage. Professional Procast CAE simulation is required before mold production to match corresponding process parameters. Each casting mold trial-test formulates exclusive verification standards according to mold type, ensuring the final mold matches actual production working conditions. Foundry enterprises need to select mold types based on casting wall thickness, precision requirements and batch output to avoid yield reduction caused by mismatched mold and process.
FAQs
Q1: Which mold has lower defect rate, LPDC or gravity casting mold? A1: Standard LPDC molds control porosity below 0.8%, better than gravity’s 1.2% standard rate.
Q2: Can gravity casting molds produce thin-wall EV parts? A2: Not recommended; stable production requires wall thickness above 5mm, far thicker than LPDC’s 3mm limit.
Q3: Do LPDC and gravity molds use different steel materials? A3: Both adopt H13 hot-work steel, only structural parameters and processes differ.
Q4: Which mold has longer service life under continuous production? A4: Gravity casting molds have 15% longer service life due to lower working pressure.
Q5: How many trial tests do gravity casting molds need? A5: 4 trial batches, one more than LPDC molds to verify filling stability.
Q6: What is the core advantage of LPDC molds over gravity molds? A6: Precise pressure control, suitable for high-precision thin-wall aluminum wheel and EV parts.
Q7: Is CAE simulation necessary for gravity casting molds? A7: Recommended, effectively optimizing flow velocity and reducing local casting defects.
