Commonly used in Dongguan precision casting is molten mold casting, also known as wax casting: select the appropriate molten mold material to make the molten mold of the molten mold, repeatedly attach the refractory coating and refractory sand to the molten mold, dissolve the hardened mold and dry the interior Melt the mold to obtain a baking mold with a cavity, and obtain sufficient strength and remaining molten mold according to product needs or heat treatment, cold processing and surface treatment. For example, sand casting, mass production factories should adopt technologically advanced modeling and core methods. The productivity of the old-fashioned vibrating or vibrating molding machine production line is not high enough, the labor intensity of the workers is large, the noise is large, and it is not suitable for mass production requirements, so it should be gradually reformed. For small castings, a water split or vertical split tankless high pressure forming machine production line can be used, and the full-size molding production efficiency is high. Various box-type high-pressure forming machine production lines and air-impact forming production lines can be selected in the middle of the small area to meet the requirements of rapid and high-precision forming production lines. Cold core boxes, hot core boxes and shells can be selected.

The shape and core of resin hard sand can be considered for medium-batch large castings.

For heavy castings produced in small batches of a single piece, manual molding is still a very important method. Manual molding can adapt to a variety of complex requirements and is more flexible, and does not require a lot of process equipment. Sodium silicate sand molds, VRH method sodium silicate sand molds, organic ester sodium silicate hard sand molds, clay drying molds, resin hard sand molds, cement sand molds and other single-piece recast parts are produced. The pit molding method has low cost and fast production. Mass production or long-term production of shaped products are suitable for multi-box modeling and split-box modeling. The investment in molds, sand boxes, etc. is high, but it can be compensated in terms of saving modeling time and improving product quality.

Low pressure casting, die casting, centrifugal casting and other casting methods, equipment and molds are expensive, and are only suitable for mass production.

The condition method must be appropriate.

In the same production of large-scale machine tools and other castings, the core molding method is generally used, instead of making patterns and sand boxes, the core is formed in the pit. Another factory uses the sand box molding method to make patterns. Different companies have different production conditions (including equipment, location, staff quality, etc.), production habits, and accumulated experience. According to these conditions, we should consider which products are suitable and which products are not suitable.

Precision requirements and cost.

The accuracy of castings obtained by various casting methods is different, the initial investment and productivity are also inconsistent, and the economic benefits are also different. Therefore, in order to achieve more, fast, better, and economical, all aspects must be considered. Make a preliminary cost estimate for the selected casting method, and determine a casting method that has high economic benefits and can guarantee the casting requirements.

The development of my country's foundry industry is in a relatively difficult period, but in the long run, there is still some hope for the development of my country's precision casting industry. Market demand is gradually recovering. Coupled with the strength of the development of my country's foundry industry, my country's foundry industry will surely gain A satisfactory result.

To fundamentally improve the level of Dongguan precision casting technology, the following four points must be achieved

1. Develop simulation technology, improve prediction accuracy, strengthen process control, and increase yield. The problem of regularity is not well mastered, which affects the yield of mass production.

2. Combination of production, education and research. In addition to enhancing innovation awareness and research and development capabilities, independent innovation of enterprises also needs to pay attention to and strengthen the integration of production, learning, and research with precision casting enterprises as the main body.

3. Pay attention to the development of materials. Materials are the foundation of industry, and there is still a lot of work to be done. In the field of aerospace, the research and smelting technology of alloy materials, especially high-temperature alloys and other new materials need to be improved, and there is still a big gap with overseas. Fourth, pay attention to the improvement of equipment and technology. Technically, it is mainly an equipment problem. Many important equipment, such as some directional solidification equipment, mainly rely on imports. Therefore, the development of precision casting equipment is still the focus.