灰铸铁泵壳粘砂缺陷的防止措施

介绍了灰铸铁泵壳铸件的结构及技术要求,详细阐述了该铸件的原生产工艺,针对原工艺存在的粘砂问题,对缺陷机理进行了分析,找出问题产生的根源,采取了以下措施:(1)型砂紧实率由32％～36％降至30％～32％;(2)型砂水分含量由3.2％～3.4％降至2.9％～3.2％;(3)湿压强度降低到0.15～0.17 MPa;(4)...

Measures to Prevent Sand Burning-on Defect of Gray Iron Pump Housing

The structure and technical requirements of gray iron pump housing were introduced,the original production method and process was described in detail.In order to solve the burning-on defect problem of original production process,the defect formation mechanism was analyzed to find the defect-caused reason,the following measures were adopted:(1)The compact-ability of the molding sand was reduced from 32%~36%to 30%~32%.(2)The moisture content of the molding sand reduced from 3.2%~3.4%to 2.9%~3.2%.(3)The green compression strength was reduced to 0.15~0.17 MPa.(4)Whether the exhaust hole was running through should be inspected during production process,and a special person was arranged to light the fire for venting.The production result showed:after above improvements,200 psc castings were produced and were shot-blast cleaned,beside 3 psc was rejected due to surface sand-drop defect,all other castings had no burning-on defect were found.