In order to verify the correctness of defect cause analysis, the project team carried out process verification test. The test was divided into group A and group B. the two groups had the same pattern and technology, and both adopted the pattern scheme shown in Fig. 1. The difference...
1.Current process Due to the serious slag inclusion problem, the white mold material is replaced by stmma, the specific gravity of the white mold is 22-24g / L, and the section size of the inner gate is 8mm × 40mm, cross section 30mm × 45mm, sprue 40mm × 400mm,...
Lost foam casting technology is widely used in the foundry industry because of its advantages of small investment, low energy consumption, good working environment, high production efficiency and less pollution emission, especially in the production of large quantities, high precision and complex structure castings. However, the lost foam casting...
The solidification process of liquid metal is divided into three phases: liquid phase, solid / liquid phase coexistence and solid phase. The thermal and mechanical properties of the material change greatly, and there may be three regions coexisting at the same time. Therefore, the stress-strain constitutive relationship of solidification...
In the solidification process, because of the wide range of crystallization temperature, the basic metal skeleton is formed first when the alloy grows from liquid to solid. At this time, the liquid and solid phases coexist. When the alloy continues to grow to solid, the liquid metal needs to...
Geometric modeling The heat transfer between the liquid metal and the pattern occurs during the filling process Where, ρ P is the density of foam pattern. ρ L is the density of liquid metal; λ L is the thermal conductivity of liquid metal; CL is the specific heat capacity...
Crawler shoe is the key component of roadheader walking mechanism, which is connected by pin to form crawler shoe chain. When one of the crawler shoes has a problem, it will affect the normal work of the whole crawler shoe chain and roadheader. Therefore, the improvement and optimization of...
① Because the preparatory work in the early stage of production is not in place, the theoretical negative pressure value of the system is designed relatively low, resulting in sand sticking defects of castings. ② Due to the low temperature of the molten metal, the casting of the workpiece...
(1) When using polystyrene foam in white mold manufacture, its density is very small, and the labor intensity of the operators is low during the operation. The foam material will not pollute the environment and damage the human body at normal temperature. It is also easy to achieve cleaner...
The refractory coating for lost foam casting consists of refractory aggregate, carrier (solvent), suspending agent, binder and other additives. ① Refractory aggregate. It is the main component of the coating for lost foam casting. It has the functions of heat insulation, isolation, anti sand sticking and reducing the surface...