汽车发动机缸体用再生砂质量参数及控制

Quality Parameters and Control for the Reclaimed Sand Used in Cylinder Casting

缸体铸件生产中，无论是机械再生砂还是热法再生砂，其质量控制指标为：SiO2含量80％-85％或90％-92％，粒度40／70或50／100，集中度≥80％，微粉含量≤0．4％，水分含量≤0．1％或≤0．15％，灼减量≤2．0％（热法再生≤0．1％），酸耗值≤5，8字试样强度0rb≥0．6MPa或0．7MPa。热法再生砂质量甚至优于新砂，可用于制作缸体铸件的任何砂芯，机械再生砂因灼减量高仅用于制作缸体铸件的外型等未被铁液全部包围的砂芯。

In the production of cylinder block casting, the quality control parameters of the mechanical reclaimed sand or heat method reclaimed sand are： SiO2 content 80%-85 % or 90%-92 %, grain size 40/70 or 50/100, concentration ratio≥80%, powder content≤0.4%, moisalre content≤0.1% or ≤0.15%, ignition loss ≤2.0 % （heat method reclaimed sand ≤ 0.1% ）, ADV ≤5, σb≤ 0.6 MPa or 0.7 MPa. The quality of heat method reclaimed sand is better than that of new sand, so it can be used to make any sand core of cylinder block casting. Mechanical reclaimed sand is only used to make the sand core which is not completely surrounded by metal melt because of its high ignition loss.