Slow wire cutting has an indispensable position in the manufacture of precision molds, especially in the manufacture of stamping dies. The punching die, the punch fixing plate, the die and the unloading plate and the like all require a slow wire cutting process. Processing quality and efficiency directly affect the assembly performance, product quality, mold life, manufacturing cycle and cost of mold parts, so it is of great significance to prevent the occurrence of abnormal processing.
1. Low processing efficiency
The slow-cut wire cutting process parts use multiple cutting processes. When the processing efficiency is low, it is necessary to distinguish whether it occurs in the main cutting process or the trimming process.
(1) Main cutting efficiency is low
In actual production, whether or not effective high-pressure flushing is the main reason for the efficiency of the main cutting process of slow wire cutting. The wire drawing speed of the wire cutting process is slow, and the processing requires high-pressure flushing to remove chips. If the upper and lower nozzles are not attached to the surface of the workpiece during processing, or if cutting occurs along the edge, the high-pressure water cannot be effectively punched into the slit, resulting in a significant reduction in processing efficiency.
For special machining (such as special materials, complex shaped step workpieces), frequent broken wires have to be modified to reduce the discharge energy to avoid broken wires. At this time, the pulse gap should be preferentially increased to reduce the frequency of the pulse discharge, which can usually solve the problem effectively. Avoiding wire breakage by reducing the machining current is also an effective method, but this method will reduce the processing efficiency more. Therefore, it is only considered to reduce the machining current only if the pulse gap is still broken.
Regular maintenance of the slow-moving wire-cutting machine is the basis for high-efficiency machining. The electrode wires obtain discharge energy through the conductive blocks, and it is necessary to ensure that they are in good contact. When the depth of the wear groove of the conductive block exceeds the radius of the wire, the position of the conductive block must be replaced. The surface of the conductive block needs to be sanded to remove the oxide layer to increase its conductivity.
If you do not clean the lower guide wire core for a long time, it will block (using the brass wire will drop the copper powder). The cooling water of the conductive block or even the flushing of the lower nozzle will seriously affect the processing efficiency. The maintenance of the lower guide wire core seat is required. When the reading of the water pressure gauge in the process differs greatly from the process setting value, the nozzle should be inspected for damage. It will affect the actual pressure of the high pressure flushing, which will greatly reduce the processing efficiency and replace it if necessary.