The role of the structure of the electroplating hanger
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Bar lift The lifting rod is usually set between the main rod and the hook, 100-150mm away from the bath solution. If the distance is less than this value, it will be contaminated by the plating solution and inconvenient to operate. The function of the lifting rod is mainly to facilitate the transfer between processes, and it can be omitted for special hanging light workpieces. Just hold the main pole directly. Because the lifting rod must bear the gravity of the weight of the workpiece during work, the lifting rod welded to the main rod must be gas-welded. The soldering strength is not good and it is easy to desolder under stress. Master pole The main rod is the main component of the whole hanger. It has to withstand the current intensity of the whole hanger and the hanging workpiece and the total support strength of the hanging workpiece itself, so the cross-sectional area of the material needs to be considered In addition to the above two requirements, it is also necessary to consider that a higher current intensity may be required in the pretreatment process before plating. For example, the current density during electrolytic oil removal is often higher than that of general plating species. Therefore, it is not enough to only calculate the passing value of the current required for this plating, and the allowable passing amount of the impulse current must also be considered. The inrush current density is usually 1 to 2 times the normal current density. Struts The pole is a branch of the main pole, and its function is to expand the distribution range of the hanger and increase the number of hooks. The support rod must bear the weight of the work piece hung by a row of hooks and the current that it needs to pass, otherwise it is easy to be deformed. Hook The hook is used to hang or clamp the workpiece. It is the part that directly contacts the workpiece. When using it, it is necessary to ensure that the workpiece does not fall off during the electroplating process, but also to ensure good contact between the workpiece and the hanger. The material of the hook should be brass wire, phosphor copper wire with sufficient strength, or stainless steel wire. The advantage of using stainless steel wire is that it is the same material as the support rod, which is beneficial to the removal of the coating. The distribution density of the hooks on the support rods should be appropriate. In addition to satisfying that each surface of the workpiece can be plated with a uniform coating quality, to prevent being blocked and bonded, it is also necessary to avoid the formation of air in the deep recessed parts of the workpiece. bag. The cross-sectional area of the hook is relatively small. If gas welding is used during assembly, it should be prevented from softening due to annealing, which will affect its load-bearing capacity. Enclosure The edge parts of some fine parts are often scorched during hang plating, which is caused by the edge effect, and the current density in these parts is relatively large. A frame around the hanger can ensure that the workpieces hung on the edge are not scorched due to the edge effect caused by the excessive concentration of power lines, and the current density can be appropriately increased so that the workpieces in the center of the hanger are also In addition to achieving the desired thickness, it has the following three functions. (1) Play the role of the main pole Ensure the current intensity required by each pole. (2) Increased the strength of the hanger Make the connection between the support poles and the main pole and the surrounding frame stronger, and reduce the possibility of bending and deformation of the hanger. (3) Play a shielding role If the work piece has not been protected, the enclosure can be insulated, which will not cause waste due to deposition of plating, and can still act as a shield for non-conductors, and can greatly extend the service life of the hanger. |