Addressing Workpiece Deformation in Wire Cutting
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Imbalanced internal stresses: Materials inherently possess internal stresses. Wire cutting disrupts the equilibrium of these stresses, causing deformation as the material seeks to restore balance.
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Workpiece structure: Workpieces with narrow and elongated shapes, as well as thin wall thickness, are susceptible to deformation during wire cutting. -
Other factors: Workpiece deformation can also result from material-related issues, problems with heat treatment, design flaws, inadequate process planning, and improper clamping and cutting path selection.
Preventive Measures to Minimize Workpiece Deformation
Pre-machining or stress relief cutting: Conducting rough machining or utilizing stress relief cutting techniques helps reduce residual stresses in the material before wire cutting, thus lowering the risk of deformation.
Machining pilot holes: When dealing with convex molds, machining pilot holes prior to the actual cutting process helps maintain stress balance and prevents deformations such as opening or closing.
Optimizing cutting paths: Proper arrangement of cutting paths is crucial. Initiating the cutting process near the clamped end, positioning cutting segments at the end of the path, and placing pause points closer to the clamped end minimize deformation resulting from improper cutting paths.
Multiple cutting passes: If workpiece deformation persists despite preventive measures, employing multiple cutting passes can be effective. This technique involves dividing the cutting process into several stages to achieve the desired accuracy while reducing deformation caused by internal stresses.
Incorporating multiple hold points: For large and complex-shaped workpieces, incorporating multiple hold points by adding several starting points along the cutting path helps distribute the cutting load and minimizes deformation.
