球墨铸铁轨道垫板在垂直生产线上的工艺改进

Casting Method Improvement of Nodular Iron Track Pad Produced on Vertically-parted Line

介绍了采用垂直分型线生产的球墨铸铁轨道垫板的原生产工艺及存在密集的砂眼、渣眼缺陷,通过对浇注系统和冒口进行改进,有效解决了大平面存在的砂眼、渣眼问题,最后指出:(1)在垂直线上生产板类铸件,可以实现液面的快速上升,避免高温铁液对砂型平面的烘烤变形,但上下部同时引入铁液且上部流量大于下部流量的浇注系统不可取,会导致型腔内铁液的严重紊流,不利于夹渣、砂粒的稳定上浮;(2)内浇道充型铁液的速度较高,不应正对砂芯或砂胎,会导致冲砂风险;(3)对于板类铸件,采用半开放式阶梯浇注系统很好地解决了原工艺存在的密集型砂眼、渣眼问题。

An introduction was made on the original casting method and caused concentrated sand inclusion and slag inclusion defects.By improving gating system and risers,the problem that the sand inclusion and slag inclusion defects on the large flat surface was effectively solved.Finally pointed out:(1)Producing board castings on vertically-parted line could realize liquid level rapidly rising to avoid the baking deformation of sand mold surface by high temperature iron liquid.However,it was not advisable to introduce the pouring system in the upper and lower parts of the casting and the upper flow was greater than the lower flow,because it would cause serious turbulent flow of the iron liquid in the mold cavity that would be unfavourable to the stable floating of the slag and sand particles.(2)Since the mold-filling velocity of iron liquid in ingate being relatively higher,in should not be facing to the sand core or sand lump,that it would cause sand washing.(3)For the board castings,using semi-unpressurized gating system could well solve the problem of former casting method of crowded sand inclusion and slag inclusions.