Difference Between Low-Pressure Injection Mould and Low-Pressure Die-Casting Mould Structural Design
The two mould types have 7 core structural differences, with design parameters differentiated by 30%–60% for different forming media.
Conclusion + Data + Explanation: Low-pressure die-casting mould bears 3 times higher thermal load than injection mould. It needs high-temperature resistant steel and enhanced cooling structure.
Conclusion + Data + Explanation: Injection mould exhaust groove depth is 0.05–0.08mm, 30% shallower than casting mould. It adapts to low-viscosity polymer melt filling.
Conclusion + Data + Explanation: Die-casting mould cavity hardness requirement is 48–52 HRC, 10 HRC higher than injection mould. It resists molten metal wear and impact.
Conclusion + Data + Explanation: Injection mould cooling channel density is 25% higher than casting mould. It meets fast solidification demand of plastic melt.
Conclusion + Data + Explanation: Die-casting mould wall thickness is 30–35mm, thicker than injection mould’s 20–25mm. It improves high-pressure structural stability.
Most industry purchasers confuse low-pressure injection mould and low-pressure die-casting mould, resulting in wrong mould selection and low production yield. Although both belong to low-pressure mould series, their forming media, working temperature, pressure load and failure mechanisms are completely different, so low-pressure mould design schemes cannot be universal.
Low-pressure die-casting mould is used for metal alloy casting, facing high-temperature molten metal impact and thermal corrosion. It has strict requirements on material high-temperature resistance, structural compression resistance and thermal fatigue resistance. Low-pressure injection mould is used for plastic polymer forming, with low working temperature and small thermal load, focusing on dimensional precision and surface finish.
Xinfeng Machinery adopts differentiated design schemes for two types of moulds. In terms of material selection, low-pressure casting mould prioritizes hot-work steel with high thermal stability, while low-pressure injection mould selects pre-hardened steel with high precision and low cost, which effectively controls low-pressure injection mould price while ensuring performance.
Exhaust structure difference is the key to distinguish the two moulds. Plastic melt has low viscosity and fast gas discharge, so shallow and dense exhaust grooves are adopted; metal melt has high viscosity and slow filling speed, needing deep and wide exhaust grooves to avoid air entrapment defects.
Cooling system design also has obvious differences. Plastic products have fast solidification speed, requiring dense cooling channels to shorten cycle; metal castings need slow and uniform cooling to avoid internal stress and shrinkage defects, so sparse and large-size cooling channels are used.
FAQ
Q1: What is the biggest difference between the two low-pressure moulds? A1: Thermal load, die-casting mould bears 3 times higher load.
Q2: How deep is the exhaust groove of low-pressure injection mould? A2: 0.05–0.08mm, shallower than die-casting mould.
Q3: What hardness does low-pressure die-casting mould need? A3: 48–52 HRC, higher than injection mould hardness.
Q4: Which mould has denser cooling channels? A4: Low-pressure injection mould, 25% higher density.
Q5: What is the standard wall thickness of die-casting mould? A5: 30–35mm, ensuring high-temperature structural stability.
