How to improve the machining accuracy of Sodick EDM?

The following are some ways to improve the machining accuracy of Sardick spark machine:

First, the selection and preparation of electrodes

Selection of electrode materials: according to the processing requirements of the selection of suitable electrode materials, such as copper electrode conductivity is good but relatively large loss, graphite electrode loss is small but the processing of the surface quality may be slightly poor, tungsten-copper and silver-tungsten alloy and other composite materials, the overall performance is better, according to the specific object of the processing and precision requirements of the trade-offs between the choice.

Ensure the precision of electrode: the manufacturing precision of electrode should be higher than the precision of workpiece, the manufacturing tolerance is usually taken as about 1/2 of the tolerance of workpiece, including dimensional accuracy, shape accuracy and surface roughness, etc., should be strictly controlled.

Optimization of electrode design: the design of electrodes should take into account the discharge gap, chip removal, heat dissipation and other factors, reasonable electrode shape and structure to help improve machining accuracy and stability, such as the use of multi-electrode machining, electrode flattening and other ways to improve the machining effect.

Second, optimization of processing parameters

Accurate control of pulse parameters: reasonable selection of pulse width, peak current and other pulse parameters, in general, reduce the pulse width and peak current can reduce the surface roughness, improve machining accuracy, but will correspondingly reduce the machining speed, according to the specific requirements of the machining in the balance between precision and efficiency.

Stable discharge gap: maintain the stability of the discharge gap is critical to the machining accuracy, can be achieved by adjusting the electrical parameters of the pulse power supply, optimize the servo control system, etc., at the same time to pay attention to the secondary discharge caused by the corrosion products on the discharge gap, clean up the corrosion products in a timely manner.

Reasonable setting of servo reference: According to the electrode material, workpiece material, machining depth and other factors, reasonable setting of servo reference to ensure that the electrode and the workpiece between the discharge state is stable, to avoid the decline in machining accuracy due to improper setting of servo reference.

Third, the management of working fluid

Select the appropriate working fluid: different working fluids have different insulation properties, cooling performance and chip removal performance, should be based on the processing requirements and electrode materials to select the appropriate working fluid, for example, in the finishing process, you can choose a lower viscosity, good insulation performance of the working fluid, in order to obtain a better machining surface quality.

Keep the working fluid clean: Replace the working fluid and filter paper core regularly to prevent the impurities in the working fluid and the products of galvanic corrosion from affecting the machining accuracy, and it is generally recommended that the filter paper core be replaced when the pressure is less than 0.18Mpa.

Optimize the working fluid flushing method: according to the processing shape and requirements, choose the appropriate flushing method, such as side flushing, bottom flushing or circular flushing, etc., to ensure that the products of galvanic corrosion can be discharged in a timely manner, and the temperature of the processing area is uniformly distributed, to avoid uneven flushing resulting in machining accuracy problems.

Fourth, workpiece clamping and positioning

Ensure clamping accuracy: the use of high-precision fixtures and clamping methods to ensure that the workpiece will not be displaced and vibration in the process of machining, the clamping force should be moderate, not only to ensure that the workpiece is firmly fixed, but also can not cause deformation of the workpiece, affecting the machining accuracy.

Accurate positioning methods: the use of appropriate positioning reference and positioning tools, such as edge finder, tool setting instrument, etc., to improve the positioning accuracy of the workpiece, the positioning error should be controlled within the allowable range to ensure the consistency and accuracy of the machining dimensions.

Fifth, the maintenance of machine tools and maintenance

Regularly check the accuracy of the machine: Regularly check and adjust the accuracy of the key components of the Shadick spark machine, such as the axes guideway and ballscrew, to ensure that the precision of the machine's axis movement, table flatness, spindle perpendicularity and other indicators to meet the requirements, it is generally recommended to inject lubricating oil into the machine tool axes guideway and ballscrew every three months.

Keep the machine clean and stable environment: keep the machine body and table clean, to prevent oil, chips and other debris into the machining area, affecting the machining accuracy, and at the same time pay attention to the temperature and humidity control of the machining environment, to avoid too large a difference in temperature leading to deformation of the machine tool, affecting the machining accuracy.

Timely maintenance and replacement of components: found that the machine parts are worn or damaged, should be timely maintenance or replacement, such as electrode chuck, wire and other parts of the damage will affect the transmission of discharge energy and machining accuracy, must be dealt with in a timely manner.