Three kinds of annealing process were selected, and the annealing time was 18 h, 11 h and 8 h, respectively. After annealing, the residual stress value detected by different processes. The test of 18 h annealing process was repeated for two rounds, and the stress at each point of...
The structure of 11 l engine cylinder head casting is shown in Figure 1, and the overall dimension of the casting is 1 002 mm × 420 mm × The average wall thickness is about 5 mm. It is required that the tensile strength of the body is more...
Through the above analysis, the process was optimized: the furnace holding time was extended to about 8 h, the temperature gradient of cooling was controlled by human intervention, and the data of casting heating, holding and cooling were collected to provide data support for subsequent improvement. The optimized annealing...
The structure of a 13 l cylinder head casting is shown in Figure 1, and the overall dimension of the casting is 1 000 mm × 400 mm × The average wall thickness is about 5 mm. The customer requires that the tensile strength of the body is more...
The residual stress of cylinder head castings has always been an important problem in cylinder head casting. After casting, due to the different cooling rate of each part of the casting, the shrinkage of each part is different, which will restrict each other and produce stress. This kind of...
With the economic development of the country, all walks of life are developing rapidly, and the machinery industry is also growing steadily, especially the forklift industry. The demand for supporting oil cylinders for forklifts is also increasing gradually. In order to complete the production tasks on time and in...
The poor machinability is a common problem of Engine Castings in China, and it is also the biggest gap between domestic castings and foreign castings. Even though the chemical composition, matrix microstructure and hardness of domestic castings and imported KD castings are similar, the machinability of domestic castings is...
Leakage refers to the leakage phenomenon of the cylinder block (cylinder head) during the pressure test (water pressure / air pressure), which mostly occurs in the water jacket cavity or oil passage cavity of the cylinder block (or cylinder head). There are two main causes of leakage: inclusion and...
Modern engines have very strict requirements on cleanliness. For cylinder block (cylinder head) castings, only a few grams (g) of sand and foreign matters are allowed to remain in the water cavity, oil cavity, tappet chamber and other parts. Many enterprises have adopted secondary shot blasting, strong shot blasting,...
Usually in the inner surface or hot spot of the casting, such as the water jacket cavity of the cylinder head, or in the inlet and outlet passage, due to the effect of high temperature molten iron during pouring, the transformation expansion of the silicon sand in the sand...