The casting blank of automobile engine cylinder head is produced by sand gravity casting. ZL105 aluminum alloy is selected as the casting material. The overall dimension of the casting is 426mm × 200mm × 131mm, the volume is 4581cm3, and the weight of the whole casting is about 12.4kg. The casting belongs to thin-walled box type parts (the minimum wall thickness is 4mm). For single piece of manual modeling, the dimensional tolerance grade is 10ct.
1. Introduction of rapid sand casting process
Rapid sand casting is to set the process parameters, sand core design, gating system design, riser design and other steps of the three-dimensional model of the casting through the rapid sand casting process CAD system, and then use the sintered SLA rapid prototype as the pattern, combined with the excellent molding ability of resin self hardening sand, directly turn over the outer mold and sand core.
In the process of single piece small batch or new product development, this technology has the characteristics of short development cycle and higher precision than the traditional sand casting, so it is a development trend to replace or improve the traditional technology by adopting the rapid sand casting technology.
2. 3D geometry modeling of engine
In this paper, ugnx8.0 software is used to model the three-dimensional model of engine cylinder head. UG NX is a new generation of digital product developed by Siemens PLM Software. The most widely used integrated CAD / CAM / CAE application suite in the world. UG NX provides a complete suite of process automation tools, enabling companies to collect and reuse product and process knowledge, thereby promoting the use of enterprise best practices. It also includes the most powerful and extensive product design application module in the world. At the same time, UG NX has high-performance mechanical design and drawing functions, providing high performance and flexibility for manufacturing design to meet the needs of customers to design any complex products. Based on the above advantages, UG nx8.0 is selected for 3D modeling of engine cylinder head.