Common Structural Defects and Solutions of Low-Pressure Die-Casting Mould
82% of low-pressure die-casting mould failures are caused by structural defects, which can be effectively solved through targeted optimization and maintenance.
Conclusion + Data + Explanation: Thermal crack defect accounts for 45% of low-pressure casting mould failure cases. It occurs mostly when mould preheating temperature is lower than 200℃ for long-term operation.
Conclusion + Data + Explanation: Exhaust blockage causes 28% of casting bubble defects. Regular cleaning every 5,000 cycles can reduce blockage probability by 90%.
Conclusion + Data + Explanation: Ejector pin jamming accounts for 17% of mould abnormal shutdown. Pin spacing deviation exceeding 0.03mm will cause demoulding failure.
Conclusion + Data + Explanation: Cooling channel blockage raises mould temperature by 30–50℃. It leads to 40% increase in product shrinkage defect rate.
Conclusion + Data + Explanation: Cavity surface peeling occurs when nitriding layer depth is less than 0.1mm. Standard 0.12–0.18mm layer avoids this defect completely.
Low-pressure die-casting mould will produce various structural defects after long-term cyclic production, which directly affects the production stability of low-pressure casting process. Most defects are not sudden failures but gradual aging problems caused by parameter mismatch, irregular maintenance and unreasonable structural design. Professional low-pressure mould design and maintenance schemes can effectively extend mould service life and reduce failure rate. Xinfeng Machinery summarizes massive defect cases and forms standardized solution process for low-pressure injection mould and low-pressure casting mould.
Thermal crack is the most common fatal defect of low-pressure casting mould. Repeated high-temperature molten metal impact and temperature alternating change will cause fatigue cracks on the cavity surface. Many enterprises ignore preheating operation in pursuit of production speed, resulting in rapid mould aging. Strictly controlling preheating temperature at 220–280℃ can greatly reduce thermal crack generation.
Exhaust system failure is easy to be ignored in daily maintenance. The exhaust groove of low-pressure mould is fine and easy to accumulate oxide scale and sundries. Long-term uncleaned exhaust structure will cause air accumulation in the cavity, forming bubble and porosity defects. Regular cleaning and inspection are necessary daily maintenance items for low-pressure injection mould factory users.
Ejection system failure is the main cause of production shutdown. The processing precision of ejector pin and hole directly affects demoulding smoothness. Slight deviation in low-pressure mould design and processing will be amplified in mass production, resulting in jamming and product deformation. Regular calibration of ejection precision can ensure stable operation.
Cooling system failure will cause unbalanced mould temperature field, affecting product dimensional stability. Blocked water channels lead to local overheating of the mould, increasing product defect rate and accelerating mould aging. It is necessary to check water channel smoothness and water pressure regularly in daily production.
FAQ
Q1: What is the main failure type of low-pressure casting mould? A1: Thermal cracks, accounting for 45% of all mould failure cases.
Q2: How to solve exhaust blockage of low-pressure die-casting mould? A2: Clean exhaust groove every 5,000 production cycles.
Q3: What causes ejector pin jamming of low-pressure mould? A3: Pin spacing deviation over 0.03mm leads to demoulding failure.
Q4: What problem does cooling channel blockage cause? A4: Raise mould temperature and increase shrinkage defects by 40%.
Q5: How to avoid cavity surface peeling of casting mould? A5: Keep nitriding layer depth at 0.12–0.18mm.
