论文部分内容阅读
北京有近万台1511MP型自动换梭纺织机,其中的驱动齿轮原用灰铁制造,磨损快,更换频繁,影响生产.从1972年改用稀土镁球铁后耐磨性明显改善,但同时带来如下问题:(1)球铁收缩大,使齿轮轮毂处出现缩孔、缩松,铸件大量报废,(2)为解决上述问题,将齿轮轴孔的砂芯改为铁芯.工艺变动后,因缩孔造成的废品率下降了,但轴孔处硬度高达HB288,出现大量自由化碳化物,使拉削键槽十分困难.如采用高温石墨化退火,则浪费能源,齿轮变形,需增加矫正设备和工序.
Beijing has nearly 10,000 sets of 1516MP automatic shuttle looms, of which the driving gear was originally made of gray iron, wear fast, frequent replacement, affecting production.Radion from 1972 to use rare earth magnesium iron significantly improved wear resistance, but at the same time Bring the following problems: (1) the ductile iron shrinks greatly, so that shrinkage holes and shrinkage appear on the gear wheel hub, a large amount of castings are scrapped, and (2) the sand core of the gear shaft hole is changed to the iron core in order to solve the above problems. After the shrinkage due to the decline in the rate of decline, but the shaft hole hardness as high as HB288, a large number of liberalized carbide, the broaching keyway is very difficult, such as the use of high-temperature graphitization annealing, the waste of energy, gear deformation, the need to increase Correction equipment and procedures.