Investigation on the causes and improvement of deformation in precision machining

The precision mechanical processing performance is not only vital to corporate interests but also safety-critical. While generating economic benefits, it significantly reduces workplace accident risks. Therefore, preventing component deformation during manufacturing is paramount. Operators must consider all relevant factors and implement preventive measures to ensure product integrity. To achieve this, analyzing deformation causes in machining processes and developing reliable countermeasures are essential. These efforts will establish a solid foundation for realizing modern enterprise development strategies.

1. Analysis of the causes of deformation in precision machining
2. The internal force causes the change of machining accuracy of parts

In lathe machining, the cohesive force principle is typically applied. By using the lathe’s three-jaw or four-jaw chuck to securely hold workpieces, precision mechanical processing can be performed. To ensure parts remain clamped under force and minimize internal axial stress, the clamping force must exceed the mechanical cutting force. The clamping force increases proportionally with the cutting force and decreases accordingly. This operational approach ensures stable force distribution during machining. However, when the three-jaw or four-jaw chuck is released, the machined parts often deviate significantly from the original design—some exhibit polygonal shapes, others become oval, resulting in substantial dimensional deviations.

2. It is easy to produce deformation after heat treatment

Sheet metal components, characterized by their large aspect ratio, are prone to developing “hat-shaped bending” after heat treatment. This deformation manifests in two primary ways: first, midsection bulging that amplifies surface flatness deviations; second, bending induced by external environmental factors. These deformation issues arise not only from altered internal stresses post-heat treatment but also stem from operators’ insufficient expertise in component structural stability, which significantly increases deformation risks.

3. Elastic deformation caused by external force

There are four primary causes of elastic deformation in mechanical processing. First, components containing internal thin plates require more precise machining techniques. When workers fail to align these components with design drawings during positioning and clamping, elastic deformation often occurs. Second, uneven surfaces on lathes and fixtures create uneven stress distribution during clamping, causing the weaker side to deform under force during cutting. Third, improper positioning during machining reduces component stiffness. Fourth, cutting forces themselves contribute to elastic deformation. These multiple factors collectively demonstrate how external forces significantly impact machining quality.