Jiangshan Huaxing Machinery factory take you to understand the cause of stomata

Jiangshan Huaxing Machinery Factory takes you to understand the causes of stomata:

01. The casting temperature is low, the metal liquid in the front of the foam filling can not be fully vaporized, and the undecomposed residue can not float to the riser, thus solidifying in the casting to form pores.

02. Fine sand particle size, large dust content, poor air permeability, negative pressure pipeline blockage caused by negative pressure deformation, so that the negative pressure value around the cavity is far lower than the indicated negative pressure, gasification can not be discharged in time, forming pores or wrinkle.

03. Low deoxidation rate of liquid steel. The slag removal is not clean, the flattening time is short, the slag blocking effect is poor during pouring, the pouring process is unreasonable, resulting in slag holes and precision casting plants.

04. The connection between the sprue cup and the sprue and the pouring system is poorly sealed, especially the connection between the sprue and the sprue cup is poorly sealed, which is easy to form sand and pores under the action of negative pressure, which can be calculated and explained by Bernoulli equation.

05. A large amount of gas and residue generated by vaporization decomposition foam model can not be discharged in time from the mold and foam. Poor drying of dry sand coating, surrounded by liquid alloy at high temperature, cracking a lot of hydrogen and oxygen into the casting is the main reason for the formation of pores.

06. The location of the opening of the inner runner is unreasonable, resulting in the formation of a dead corner area during filling. Due to the pressure effect of the gas in the mold cavity, the gasification residue accumulates in the dead corner to form pores.