心轴径向小孔镀硬铬工艺

Technological Research on the Hard Chromium Plating in Mandrel Radial Holes

为了提高产品备件心轴的使用寿命,距心轴两端35mm处有两个对称的d=25mm,l=25mm径向小孔设计增加镀铬要求。心轴的外廓尺寸为d=45mm,l=1990mm,镀件细而长、孔径小而浅。造成施镀过程中,镀铬阳极的绝缘、支承、定位、固定和镀件在镀铬槽中的摆放方位及施镀过程中电流控制等难度。结合以往经验,利用现有镀铬设备,经实验确定了工艺方案,设计制作了合理的镀铬工夹具,使该件镀铬获得了成功。

In order to improve the service life of mandrel of the spare part, hard chromium plating was conducted in two symmetrical radial holes which located at the place 35mm away from the two ends of the mandrel and with a size of d =25mm,1 =25mm. The outer size of the mandrel is d =45mm,1 = 1990 mm, the plating part is thin and long while the holes are small and fleet. All of these made the electroplating process become difficult such as the insulation, supporting, orientation and fixation of the ehromeplate anode, the placing orientation of the plating part in the bath as well as the controlling of the low current during the plating. Combining anciently chromeplate experience and the existing chromeplate equipment, a final technology scheme was determined. And then a rational fixture was designed and made and the hard chromium plating was successfully realized.