【摘要】 气冲压板紧实砂型是先在砂型背面复盖一块钢板,然后再进行气冲紧实的方法。气冲压板紧实砂型的过程可分为型砂加速运动的初步紧实、底板冲击紧实和压板反冲击再紧实三个阶段。由于该法对机器开阀速度要求不高,从而简化机器快开阀的设计。用这种方法紧实的砂型背面平整、紧实度高而均匀;当压板厚度适当和压板与砂箱壁间隙最小时,紧实效果最好;在压板上与模项相对的区域钻些小孔或装些通气塞可以大大提高砂型深凹区的紧实度和砂型的匀实性。更多还原

【Abstract】 The method discussed in this paper includes a sand filled mold couered with a press-oard on its top and then compacted with air pressure acting.Experiments show that the process of air acting press oard impact consists of three stage : initial compa ctingof the downward accelerating sand,bottom-late impact compacting and the press oard reverse impact compacting. With this method,foundry molds with high and uni?form compactness are achived.Lower necessary openning velocity and-thus simples con?struction of quick-penning valve then used for air impact compacting machines can be used.A proper thickness of press-oard and suall gap between pressoard and flask all are favorable for compacting the mold.When the mold contents a tall pattern with broad top surface,some vents in the center of press-oard are advantageous for high and uniform bulk-ensity distribution after compacting.更多还原