CAD–FEA Integrated Automation Platform for Structural Design, Deformation Simulation, and Size Optimization of Housings in External Gear Pumps

External spur gear pumps are widely employed in hydraulic systems for their simplicity, efficiency, and cost-effectiveness; however, the conventional CAD-based methods used to design these components remain time-intensive and prone to inconsistencies, particularly during iterative structural analysis and optimization. To address these limitations, this study presents a parametric, automated design platform for external spur gear pumps by integrating the SOLIDWORKS API with a custom C# desktop application. The tool automatically generates 3D solid models and facilitates strength analysis and housing wall-thickness optimization through a user-friendly interface. Geometric and hydraulic inputs are used to define model parameters and simulation conditions, into which an empirical pressure distribution model, derived from prior experimental data, is embedded to establish accurate boundary conditions. This integrated configuration enables structural analysis in SOLIDWORKS Simulation, allowing systematic variation of wall thickness and geometry within prescribed constraints. Results from the case study yielded a configuration achieving an 18.42% reduction in housing mass while maintaining a minimum factor of safety of 3.948 and a maximum deformation of 0.012 mm. The system effectively reduces design time, improves repeatability, and minimizes human error, while demonstrating robustness across varied design scenarios. Overall, the proposed approach provides a practical and efficient solution for automated design and optimization of external gear pumps, supporting parametric flexibility and advancing CAD/CAE integration in hydraulic component design workflows.