Research and Application of Lost Foam Casting Technology for Automobile Engine Cylinder Head (2)

1. Engine block foam model structure process design

(1) At present, there are big differences in the structural design of the foam model of diesel engine and gasoline engine block at home and abroad, and the process from the splitting scheme to the die is different. In Europe and the United States, the method of splitting from the cylinder head joint surface to the oil pan surface level (including “V” shape and in-line cylinder block) is used in the sizing scheme, as shown in Figure 1. The advantage of this type of division scheme is that it is advantageous for automatic mass production, and the glue lines do not interfere with each other, and the glue quality is guaranteed; the disadvantage is that there are many glue lines and most of them are distributed on the non-machined surface, and the overall aesthetic appearance Not as good as ordinary sand castings. The larger part of the matching die process is to partially seal and hollow the crankcase along the die-cutting direction, as shown in Figure 2.

The advantage of this die processing scheme is that it is advantageous to realize the simplification of the mold structure, and thus has a positive driving effect on the foam forming stability of the die and the improvement of the mold-making efficiency; the disadvantage is that although the thickness of the die is partial Large wall thickness treatment was adopted to minimize the weight increase of the casting due to local sealing, but due to the limitation of the height of the die and the strong tightening force of the die on the island mandrel, The effect of hollowing out is unsatisfactory.


(2) The engine cylinder lost foam process schemes in some Asian countries can be roughly classified into two types: 1 The overall shape and internal inlay cylinder-type process represented by Japan (as shown in Figure 3). 2 The process of combining horizontal classification and vertical classification represented by China (as shown in Figure 4).

The advantages of the overall shape molding and the internal inlaid cylinder sleeve type division scheme are that the main body model has good rigidity, beautiful appearance, small amount of glue, high dimensional precision, and the cylinder mold separate molding reduces the difficulty of foam forming of the mold piece. The disadvantage is that the sealing surface appears in the vertical direction when the cylinder liner die is glued to the overall shape of the die. When the mechanical operation is completely relied on, the bonding quality cannot be ensured, and it is necessary to cooperate with the artificial glue. Reduced production efficiency, but also brought hidden dangers to the stability of quality. The larger part of the matching die processing is to partially seal the crankcase along the die-cutting direction, and to make the wall thickness of the crankcase from the outer wall of the crankcase to be hollowed out, as shown in Figure 5. .

The advantage of this die processing solution is that the weight of the casting can be minimized, and the shrinkage force of the foamed die to the side core can be effectively reduced (the formed pellet used for the hollowing process can be mounted on the side as a whole) The core mold is used to improve the forming quality of the foamed mold. The matching crankcase punching die adopts a forming process combining integral demoulding and partial sliding block, which has the advantages of increasing the flexibility of foaming die forming and reducing the blockage area of ​​the component structure; The molding process becomes complicated, which prolongs the molding cycle of the foamed mold and shortens the service life of the mold.

Previous Next

Far Infrared Sauna Room

Far Infrared Sauna Room

Far Infrared Sauna room

Guangzhou Aijingsi Sanitary Products Co.,Ltd , https://www.comoxvalleyhottubs.com