QT600-8齿轮盘的生产工艺

Production Method and Process of QT600-8 Nodular Cast Iron Gear

介绍了QT600-8齿轮盘的技术要求和生产工艺。铸件质量55 kg,外径460 mm,主要壁厚50 mm;抗拉强度要求与常规球铁牌号QT600-3相同,但伸长率要求提高到8%,金相组织要求单位面积球数不少于120个/mm^2。采用呋喃树脂砂造型,铸造工艺为:铸件底部设4道内浇道,铸件顶面中心设保温冒口,热节部位设随形冷铁。铁液熔炼、浇注工艺为:采用中频感应炉化铁,RE-Mg球化剂盖包法球化处理以及多次孕育处理;浇注后在浇口杯顶面覆盖干砂保温,并延长保温时间。试制结果显示,齿轮力学性能、金相组织均符合要求,铸件解剖未发现缺陷。

The technical requirements and production method and process of a plate-shaped gear were introduced. The technique requirements were as followings： weight of the casting was of 55 kg. Its outer diameter was of 460 mm, its main wall thickness was of 50 mm,the tensile strength requirement was the same as the that of the normal nodular iron grade QT600-3, but the elongation requirement was elevated to 8%,its metallographical requirement included that the nodule count must be not less than 120/mm2. The furan resin sand was used for molding. The casting method was as：4 ingates were set at the bottom of the casting,a insulated riser was set at the center of the top surface,and a configuration-following chill at the hot spot. The iron-melting,treating and pouring process were as：the medium frequency induction furnace was used for iron melting,RE-Mg nodularizing alloy and Tundish ladle process were used for nodularizing,muhiple-inoculating process was used. The top surface of the pouring basin was covered with dried sand after pouring finished, and the temperature-holding time was prolonged. The result of the trial production showed that both the mechanical properties and metallographical structure of the gear met the requirements,no defects were found by dissecting the casting.